Loudspeaker Design Project - VPA Wiki

Transcription

Loudspeaker Design Project - VPA Wiki
Loudspeaker Design Project
Kyle Persohn
Fall 2007
Transducer Theory
Michigan Technological University
Loudspeaker Design Project – Kyle Persohn
Table of Contents
Datasheet
Design Statement
Initial Design
Revised Design
Final Design
Cabinet Design
Crossover Design
Accounting
Drafting
Construction
As-Built Plans
Initial Listening Evaluations
Testing and Tuning
Final Listening Evaluations
Final Report
Gallery
ThankYou
for providingdriversandcrossoverpartsat
I owe verybigthanksto MadisoundSpeakerComponents
educationalratesto makethis projectpossibleon a strictbudget. In particular,thank to AdamJohnson
who took time out of hisafternoonto helpinspirethis finaldesign.I highlyrecommendMadisoundto
anyspeakerbuilderlookingfor an onlineretailerwho providesa vastproductrange,competitive
pricing,andexcellentcustomersupport.
?r'
fu-nunaot
Foi/rr(-totd.€fu,n
tladlsound
Scan-spek - LPG
Speaker
Peerless-Seas-Keiga
Gomponents,lnc. HhVi-Audax-Hovland
Founhk - Accubn
Distributorof Loudspeakers& ComponentsWorldwide
Mr. Adam Johnson
P.O,Box1l28g
Tcl:008{11-3433
Mafion, YU537ll4USA
F.x:C0E-E31€771
www.firdaound.oofvl
*mQmeOlound.cofn
WinSpeakerz Modeled Plots
450 Watts Input Power
Frequency Response
Features
•
•
•
•
•
•
•
•
•
High SPL ouput
Deep low-frequency extension
Affordable user replaceable
voice coil on tweeters
Horn-loaded directivity
Dome tweeter clarity
Even frequency response
Robust finish
Excellent mechanical grounding
Solid construction
Impedence
Linear Excursion
Specifications
Dimensions
WXHXD
12.50” X 61.00” X 13.00”
Connectors
NL-4 Speakon
Frequency Response
38 Hz – 19.5 KHz (est.)
Max SPL Output
119 dB (modeled)
Power Handling
Up to 450 Watts (est.)
Woofers
Peerless 10” 830668
Tweeter
Morel MDT37
Copyright © 2007 Kyle Persohn, All rights reserved. Other brand names are trademarks or registered trademarks of their respective owners.
Transducer Theory [FA4740]
Fall 2007
These HiFi PA speakers are designed for use in the Ensemble Room (209) in
the Michigan Tech Rozsa Center. This acoustical system provides a unique
balance between volume capability and audio quality bringing you hard
hitting bass and elegant treble at impressive volume levels.
Featured in this system are two Peerless 830668 10” Woofers and a Morel
MDT37 per cabinet arranged in a “woofer-tweeter-woofer” configuration.
The WTW arrangement allows the high and low frequencies to blend on the
listening plane (tweeter height). The listening plane is conveniently located
at ear level when sitting at the computer workstation in Room 209. The use
of two woofers utilizes the combined audio power of two lower sensitivity
but higher quality drivers to blast low frequency extension at high volumes.
The mini horn-loaded MDT37 boasts the directivity and high SPL of a
compression driver while still maintaining the smoothness and lower
distortion characteristics of a dome tweeter.
A passive 4th order Linkwitz-Riley crossover network provides the frequency
separation between the high frequency tweeter and the low frequency
woofers. The L-R design is favorable over the traditional Butterworth design
because there is a flat 0db response at the 2 KHz crossover point instead of
the normal 3db peak.
This 4th order vented box in constructed primarily of MDF with A/C plywood
reinforced baffles and cross-bracing. The dual baffle design keeps cabinet
resonance to a minimum because the varying density materials discourage
standing waves. Internal dampening features Black Hole acoustic foam to
reduce unwanted reflections. The 2” ABS port is located well below listening
plane where airflow will not disturb performance. A coating of black truck
bed liner gives the outside finish a robust look and feel. Adjustable floor
spikes provide cabinet balancing and additional mechanical grounding on
carpeted surfaces resulting in tight, punchy bass.
Sign up for swipe access in the VPA office to try them for yourself!
Professional Sound
High Fidelity PA Speaker
Designed
& Built By:
Kyle Persohn
Transducer Theory
Loudspeaker Design
Statement
Kyle Persohn
FA4740
Christopher Plummer
Michigan Technological University
Design Statement
Persohn
Introduction
The speakers to be built are being designed for the Visual and Performing Arts Department of
Michigan Technological University. They are intended for use in the Hagen Practice (Rozsa 209) also
known as the Ensemble Room. The design will borrow concepts from PA speakers in efforts to achieve
high volumes, however a higher emphasis will be put in fidelity and bass response than one would find
in a traditional PA cabinet. The completed set is expected to meet these requirements:
•
•
•
•
•
•
•
Reasonably sized, but well mechanically grounded
Directed coverage
Bass response below 60Hz
High sensitivity/SPL at least 93dB
Driver selections and crossover design that keep audible breakup modes to a minimum
Robustness for a college environment
Strict budget of $600
Budgeting
I started my driver hunt with budget as the primary limiting factor. Using the general guideline of
40% drivers, 35% crossover, 25% cabinet, I allocated a reasonable amount of resources and used that to
limit the overwhelming choices of drivers. Preliminary searches yielded some promising options from
Selenium, Eminence, Peerless, and B&C. I originally disregarding Peerless for not having enough
sensitivity and the Seleniums were negated for their questionable quality. After examining a few
specification sheets, I came to the quick realization there is a heavy tradeoff between cost, sensitivity,
and bass response (and enclosure size; however, I decided I could be the most flexible with this
variable). It is extremely difficult to find economically priced drivers that have a pro-sound level SPL
output without sacrificing low end response.
Drivers
Originally, I was open to 2-way and 3-way designs. With hopes of having better bass response I
looked briefly into 3-way designs. With the additional driver and doubling of crossover parts these
systems met the physical specification requirements the best; however they didn’t quite make the
Page 2 of 9
Design Statement
Persohn
budget cutoff. I then focused mainly on 2-way designs primarily for budgetary reasons with hopes of
maximizing whatever bass response I could get out of them. My first potential system had an Eminence
Alpha-8A woofer paired with a B&C DE-10 compression tweeter. I came across the Eminence drivers on
cost based searches and I sought out the B&C tweeters from a review on the Loudspeaker Designer’s
Selection Guide. In contrast to the suspiciously smoothed looking frequency response graphs of the
Selenium drivers, the B&C plots resembled measurements taken by a third party (Stout, 2007). This
system had high sensitivity while still making the budgetary cutoff. Unfortunately when following the
manufactures recommended tweeter crossover point, much of the driver top end break up would be
audible. I chose to replace the B&C with an Eminence PSD2002 which features a 2” voice coil allowing it
to crossover slightly lower and eliminating more of the woofer’s breakup. Upon modeling this design in
WinSpeakerz I was disappointed to discover the design was only going to get a response down to 80Hz
at -3dB (See Figure 1).
Figure 1: Eminence Alpha-8A
Page 3 of 9
Design Statement
Persohn
Woofer Selection
A reasonable compromise is to add a second driver to a 2-way system. Having a second driver
expands the possibilities to woofers that might not necessarily have a high enough sensitive by
themselves. By combining two high fidelity drivers their combined SPL output can reach that of prosound drivers. This opened up a realm of drivers I had discounted before due to their inadequate
sensitivity. The Peerless SLS 830668 10” woofer, for example, has an SPL of 88.7dB, but combined with a
second can approach 95dB. This particular driver also has a suitable response down to 38 Hz which is
considerably better than the previously mentioned 2-way design (See Figure 2). This compromise adds
some additional expense to the traditional 2-way design by adding an extra driver; nonetheless, with
half of the crossover parts necessary as a 3-way design this revised 2-way has bass response at a
reasonable cost (Electus, 2001). Although a bit on the pricey side, dual woofers in a 2-way configuration
seem to be the best balance between SPL, bass response, and cost-effectiveness.
Figure 2: Peerless 830668
Page 4 of 9
Design Statement
Persohn
Tweeter Selection
With the initial 2-way design it seemed necessary to use a compression driver as a tweeter to get
the high sensitivity required by the system. I looked at many compression drivers that were easily hornloadable to obtain some directivity and additional SPL. In my readings, I discovered some of the
negative effects that keep horn-loaded designs out of most studios and are limited to PA systems where
quality isn’t so much of an issue (Newell, 2007). A horn provides additional SPL through directivy but at
the cost of negative diffraction effects in comparison to a flush-mounted dome tweeter. To combat
these issues, I then looked at waveguides which balance the directivity of a horn while exhibiting less
horn-like distortion. A waveguided tweeter probably would work for this application; however,
compression drivers still have a “harsh” reputation that makes them less suitable for high fidelity
applications. The Morel MDT 37 turns out to be an affordable dome
tweeter set back in self contained horn-loaded enclosure (See Figure 3).
This tweeter has SPL capabilities of a PA tweeter with the aural reputation
of a hi-fi transducer (Johnson, 2007). As an added bonus, the MDT 37 has
an affordable and easily replaceable voice coil making it ideal for situations
Figure 3: Morel MDT37
where some forgiveness is necessary.
Crossover
With a fairly large woofer and a tweeter that doesn’t extend too far into the midrange, picking a
crossover point was simply a matter of keeping the audible breakup to a minimum. With a 2-way
system there really doesn’t seem to be a good solution to avoiding a crossover around 2 KHz. This is also
another reason I was in favor of a 3-way system at one point. Having two crossovers would allow more
flexibility to avoid 2 KHz, the ear’s most sensitive region. Rather than waste money trying to move the
crossover one way or another it seems most logical to use physics and the behavior of the electronic
crossover components to financial advantage. By keeping the crossover at 2 KHz the capacitors and
Page 5 of 9
Design Statement
Persohn
inductors should be more affordable, therefore allowing money to be spent on quality and order instead
of nominal value (Electus, 2001). With the crossover budget dedicated to more components of a higher
quality, I hope to create a fourth order crossover that has a narrower frequency bandwidth around the
ear’s sensitive range instead of a wider band at an alternate frequency. This narrows the problem
directly at the source and overall seems more economically efficient. Again, the 2 KHz crossover is
threading the needle between the breakup points of my drivers therefore not leaving much flexibility to
keep my goal of minimizing the audible breakup.
Enclosure
The ideal enclosure design for this system would be a 2nd order sealed box. While the Winspeakerz
plot of this arrangement is very appealing, the required volume of 15 cubic feet is quite oversized for
this application. An isobaric design using double the drivers was considered, however the extra cost
involved cannot be accounted for in the budget. Having the additional drivers would have allowed for a
more reasonable enclosure size and still maintain the desirable sealed box response curve.
The next best option turns out to be a 4th order vented design. This enclosure has a reasonable
volume around three cubic feet and still has excellent bass response when modeled with an estimate of
the room gain. While studying the driver design at Madisound, I got to see how Peerless constructed this
particular driver with lots of space for airflow and additional linear displacement for maximum excursion
without damaging the driver. When modeled in Winspeakerz, this design reaches down to 38 KHz, well
under my target low frequency goal. To handle diffraction I have the smooth channel of the horn
working to my advantage moreover I additionally plan to round the front corners of the box with a
router to mitigate high frequency diffractions. For easy routing, the enclosure will be constructed mostly
out of MDF. Plywood will be added to the front and back panels to provide additional support as well as
some dampening from the change in resonant material.
Page 6 of 9
Design Statement
Persohn
I would have liked to experiment with some of the internal lattice designs for additional support;
however the complexity and construction tools required make lattices a bit beyond the scope of this
design project (B&W Group Ltd). The B&W bracing methods often employ lots of circles that are cut out
from the main bracing piece. This is ideal because the brace can be one solid unit that is more ridged
than multiple braces joined together. The circle cut outs provide the necessary airflow and volume
reduction while maintaining a strong architectural structure that dates back to usage in Egyptian
aquaducts.
Considering I don’t have the necessary resources to experiment with B&W’s approach, crossbraces will be added as the North Creek method suggests minimizing standing waves in the cabinet
walls. With one brace placed at just over half-way between the unsupported panels, two different
resonant frequencies are created within the same chamber. The first common wavelength between
these two frequencies doesn’t occur until many multiples beyond the cabinet’s fundamental frequency.
This helps mitigate standing waves within the enclosure. These braces will be constructed out of
plywood and implemented to support the sides not reinforced by the double baffle.
While volume wasn’t a huge consideration of mine from the start, the end result seems reasonable
and I’m comfortable with building a speaker with that volume in a tower configuration. The drivers will
be laid out in a “woofer tweeter woofer” configuration. This will centralize the high frequencies within
the woofers and avoid the undesirable sound of the tweeter
off by itself (Cal Poly AES, 2005). I really like the sound of the
CM-7 towers and I would like to model the character of this
system after their design (See Figure 4). The CM-7 tower is an
MTM speaker designed by North Creek that is a common
benchmark for Loudspeaker comparison around Michigan
Tech. By implementing the North Creek bracing strategy and
Figure 4: CM7 MTM Towers
Page 7 of 9
Design Statement
Persohn
the WTW design I hope to achieve similar character to the CM-7’s. Lastly, the finished cabinet will be
coated with truck bed liner to provide a durable finish suitable for the college environment.
Application Notes
To raise the cabinet to the desired listening plane, some extra volume will be necessary in a
separate compartment from the loudspeaker itself. This will appear as one integral cabinet; however
the additional space under the cabinet will give the overall system increased height so the tweeter is
level with the listener’s ear. Furthermore, an additional plane should be placed between the speakers to
create one smooth baffle across the stereo image. This space could be expanded to act as a bass trap
once the system is tuned, however will not be included in the scope of this project. Measurements
specific to the acoustical space and system will be necessary to optimize this design.
Summary
This system will serve as a high fidelity PA system. The chosen dual 10” Peerless SLS woofers in
conjunction with a Morel MDT 37 dome tweeter provide the best compromise between cost, frequency
bandwidth, and sensitivity. The horn-loaded dome tweeter is the best example of how this design
bridges the gap between sounding good and sounding loud. This design runs down a hard fault between
PA systems and high fidelity speakers. In doing so tradeoffs had to be made, nonetheless informed
decisions were made to attempt to minimize negative effects on the system as a whole.
Page 8 of 9
Design Statement
Persohn
Works Cited
B&W Bowers & Wilikins [Motion picture]. (n.d.). England: B&W Group Ltd.
Dickenson, V. (1991). The Loudspeaker Cookbook (4th ed.). Petersbourogh, NH: Old Colony Sound Lab.
Electus Distribution. (2001). Design Your Own HiFi Speaker Crossovers [Data file].
Jeremy. (2005). Loudspeaker Enclosures [Data file]. Cal Poly AES.
Johnson, Adam. [Interview] Middleton, WI: 2007.
Newell, P. (1995). Studio Monitoring Design. Woburn, MA: Focal Press.
Newell, P., & Holland, K. (2007). Loudspeakers for Music and Reproduction. Burlington, MA: Focal Press.
Stout, B. (2007). Compression Drivers. In LDSG. Retrieved September 29, 2007, from
http://ldsg.snippets.org/sect-6.php#DRVRS
Page 9 of 9
Initial Design
My initial design for this project was very budget driven. Not knowing where else to start, I
allocated some money for drivers and started hunting on PartsExpress.com. The following pages are
specification sheets of eventually rejected drivers. These drivers are 8” woofers and horn ready
compression drivers. The 8” woofers were failed attempts at trying to squeeze bass response out of an
inexpensive two say system. The choice to use horn-loaded compression drivers for the high end was
influenced by their capability to direct sound for high SPL and their wide use in commercial PA speakers.
Shortly after researching these drivers I was granted a much larger budget and quickly moved on to
other brand names. The frequency responses of the woofers worried me the most and I knew I would
be disappointed with their bass response the most. The horn research I did while investigating this
design turned out to be the most valuable information that still had an influence in my final design.
PROFESSIONAL LINE - Woofer
8PW3
LOUDSPEAKERS
Professional 8” woofer designed to meet a variety of
PA needs for small and medium-sized rooms, with excellent
performance in the mid and low frequency ranges.
For sound reinforcement in nightclubs, dancing halls,
auditoriums, bands and also for studio m onitors.
Its great efficiency in sound reproduction is due to the
excellent combination of the different components:
- The light cone manufactured with long fiber pulp
together with a surround of impregnated fabric give the
array great stability, high yield and low distortion.
- The voice coil is made of high temperature wire,
®
wound on Kapton former.
- The epoxy painted reinforced steel frame provides
the array with high mechanical resistance.
- The use of highly resistant adhesives guarantees
optimal cohesion and durability of components.
SPECIFICATIONS
Nominal diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205 (8)
Nominal impedance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Minimum impedance @ 280 Hz. . . . . . . . . . . . . . . . . . . . . . . 7.0
Power handling
1
Musical Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . 250
2
AES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125
Sensitivity (1W/1m) averaged from 100 to 6,000 Hz. . . . . . . 92
Power compression @ 0 dB (Nom. power). . . . . . . . . . . . . . 3.9
Power compression @ -3 dB (Nom. power)/2 . . . . . . . . . . . 2.6
Power compression @ -10 dB (Nom. power)/10 . . . . . . . . . 0.3
Frequency response @ -10 dB . . . . . . . . . . . . . . . . 70 to 8,000
mm (in)
Ω
Ω
W
W
dB SPL
dB
dB
dB
Hz
1
Specifications to handle normal speech and music program material with 5% maximum
acceptable distortion on amplifier. Power is calculated taking into account the true RMS
voltage at amplifier output along with transducer nominal impedance.
2
AES Standard (100 - 1,000 Hz).
THIELE-SMALL PARAMETERS
Fs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
Vas. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 (1.02)
Qts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.81
Qes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.88
Qms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.64
ηo (half space) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.22
Sd. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.0250 (38.8)
Vd (Sd x Xmax) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58.75 (3.59)
Xmax (max. excursion (peak) with 1 0% distortion) . . 2.35 (0.09)
Xlim (max.excursion (peak) before physical damage). 8.0 (0.32)
%
m2 (in2 )
cm3 (in 3 )
mm(in)
mm(in)
Atmospheric conditions at TS parameter measurements:
Temperature. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 (77)
Atmospheric pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1,002
Humidity. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
°C (°F)
mb
%
Hz
3
l (ft )
Thiele-Small parameters are measured after a 2-hour power test using half AES power .
A variation of ± 15% is allowed.
ADDITIONAL PARAMETERS
β L . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.9
Flux density . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.10
Voice coil diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 (1.3)
Voice coil winding length. . . . . . . . . . . . . . . . . . . . . . . 9.5 (31.2)
Wire temperature coefficient of resistance (α25) . . . . . 0.00342
Maximum voice coil operation temperature. . . . . . . . 250 (482)
θvc (max.voice coil operation temp./max.power) . . 2.00 (3.86)
Hvc (voice coil winding depth) . . . . . . . . . . . . . . . . . 11.0 (0.43)
Hag (air gap height). . . . . . . . . . . . . . . . . . . . . . . . . . . 6.3 (0.25)
Re . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.4
Mms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11.1 (0.0245)
Cms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 337.2
Rms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.7
NON-LINEAR PARAMETERS
Le @ Fs (voice coil inductance @ Fs) . . . . . . . . . . . . . . . 1.277
Le @ 1 kHz (voice coil inductance @ 1 kHz) . . . . . . . . . . 0.606
Le @ 20 kHz (voice coil inductance @ 20 kHz) . . . . . . . . 0.259
Red @ Fs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.14
Red @ 1 kHz. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.50
Red @ 20 kHz . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22.39
Krm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.563
Kxm. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.261
Erm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.902
Exm. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.716
Page: 1/2 Ed.: 00 - 04/01
Tm
T
mm (in)
m (ft)
1/°C
°C (°F)
°C/W(°F/W)
mm (in)
mm (in)
Ω
g (lb)
µ m/N
kg/s
mH
mH
mH
Ω
Ω
Ω
mΩ
mH
ADDITIONAL INFORMATION
Magnet material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Barium ferrite
Magnet weight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 560 (20) g (oz)
Magnet diameter x depth . . . . . . . . . . . . . . 115 x 14 (4.53 x 0.55) mm (in)
Magnetic assembly weight . . . . . . . . . . . . . . . . . . . . 1,520 (3.35) g (lb)
Frame material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Steel
Frame finish . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Black epoxy
Magnetic assembly steel finish . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Zinc-plated
Voice coil material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Copper
Voice coil former material . . . . . . . . . . . . . . . . . . . . . . . . . . Polyimide (Kapton®)
Cone material. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Long fiber pulp
3
Volume displaced b y woofer . . . . . . . . . . . . . . . . . . . . 0.6 (0.021) l (ft )
Net weight. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1,780 (3.92) g (lb)
Gross weight. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2,000 (4.41) g (lb)
Carton dimensions (W x D x H) . 20.5 x 20.5 x 9 (8.07 x 8.07 x 3.54) cm (in)
MOUNTING INFORMATION
Number of bolt-holes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Bolt-hole diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.0 (0.20) mm (in)
Bolt-circle diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . 194 (7.64) mm (in)
Baffle cutout diameter (front mount) . . . . . . . . . . . . . . 180 (7.09) mm (in)
Baffle cutout diameter (rear mount) . . . . . . . . . . . . . . . 185 (7.28) mm (in)
Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Push on terminals
Polarity . . . . . . . . . . . . . . . . . . . . . . . . . . Positive voltage applied t o the p ositive
(+) terminal gives f orward cone motion
Minimum clearance between the back of the m agnetic assembly and the
enclosure wall. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75 (3) mm (in)
ø 204
4x ø 5,0
86
9
50
27
Dimensions in mm.
PROFESSIONAL LINE - Woofer
8PW3
LOUDSPEAKERS
RESPONSE CURVES (0° AND 45°) IN A TEST ENCLOSURE INSIDE AN
ANECHOIC CHAMBER, 1 W / 1 m
POLAR RESPONSE CURVES
50 Hz
110
30°
100 Hz
330°
-10
60°
100
0
-6
300°
-20
dB
90°
30°
0
-6
250 Hz
330°
-10
60°
0
-6
330°
-10
60°
300°
-20
dB
270° 90°
30°
300°
-20
dB
270° 90°
270°
90
240°
120°
150°
180°
240°
120°
210°
150°
330°
30°
180°
240°
120°
210°
150°
330°
30°
180°
210°
80
500 Hz
30°
70
20
200
Hz
2k
Response Curve at 0°.
Response Curve at 45°.
300°
-20
dB
90°
20k
800 Hz
-10
60°
60
0
-6
240°
150°
IMPEDANCE AND PHASE CURVES MEASURED IN FREE-AIR
180°
90
30°
330°
30°
45
300°
-20
dB
90°
240°
0
150°
180°
210°
0
-6
60°
240°
150°
180°
0
-6
330°
-10
60°
300°
-20
dB
270° 90°
120°
180°
210°
4 kHz
30°
300°
-20
dB
270°
240°
150°
330°
-10
270° 90°
120°
40
180°
300°
120°
210°
3.15 kHz
-10
60°
60
0
-6
240°
150°
330°
-20
dB
270° 90°
120°
0
-6
-10
60°
300°
-20
dB
210°
2 kHz
80
1.25 kHz
-10
60°
270° 90°
120°
0
-6
270°
240°
120°
210°
150°
180°
210°
Polar Response Curve.
20
-45
0
-90
20
200
Hz
2k
20k
Impedance Curve.
Phase Curve.
HARMONIC DISTORTION CURVES MEASURED AT 10% AES INPUT
POWER, 1 m
140
HOW TO CHOOSE THE RIGHT AMPLIFIER
The power amplifier must be able to supply twice the RMS driver power. This
3 dB headroom is necessary to handle the peaks that are common to
musical programs. When the amplifier clips those peaks, high distortion
arises and this may damage the transducer due to excessive heat. The use
of compressors is a good practice to reduce music dynamics to safe levels.
FINDING VOICE COIL TEMPERATURE
It is very important to avoid maximum voice coil temperature. Since moving
coil resistance (RE ) varies with temperature according to a well known law,
we can calculate the temperature inside the voice coil by measuring the
voice coil DC resistance:
R

1
TB = TA +  B − 1  TA − 25 +
α 25
 RA




120
T A , TB= voice coil temperatures in °C.
R A , RB= voice coil resistances at temperatures T A and TB, respectively.
α25= voice coil wire temperature coefficient at 25 °C.
100
POWER COMPRESSION
Voice coil resistance rises with temperature, which leads to efficiency
reduction. Therefore, if after doubling the applied electric power to the driver
we get a 2 dB rise in SPL instead of the expected 3 dB, we can say that
power compression equals 1 dB. An efficient cooling system to dissipate
voice coil heat is very important to reduce power compression.
80
60
20
200
Hz
Response Curve.
Distortion Curve, 2nd harmonic.
Distortion Curve, 3rd harmonic.
20k
NON-LINEAR VOICE COIL PARAMETERS
Due to its close coupling with the magnetic assembly, the voice coil in
electrodynamic loudspeakers is a very non-linear circuit. Using the nonlinear modeling parameters Krm, Kxm, Erm, Exm from an empirical model,
we can calculate voice coil impedance with good accuracy.
SUGGESTED PROJECTS
For additional project suggestions, please access our web site.
TEST ENCLOSURE
19-liter volume with a duct ø 3” b y 2 ” length.
®
Kapton : Du Pont trademark.
Specifications subject to
change without prior notice.
Page: 2/2 Ed.: 00 - 04/01
EUROPE Address:
USA Addr ess:
BRAZIL Add ress:
SELENIUM EUROPE
SELENIUM LOUDSPEAKER USA
ELETRÔNICA SELENIUM S.A.
Rohrbergst rasse 23B
1701 South Park Court, Bldg 102
BR 386 Km 435 / 92.480-000
D-65343 Eltville - Germany
Chesapeake, VA 23320 - USA
Nova Santa Rita - RS - Br azil
Phone: +( 49) 6123 601570
Phone: (757) 424-7516 / (800) 562-0510
Fax: +(5 5) 51 479- 1120
Fax: +(49) 6123 601587
Fax: (757) 424-5246
URL: www.selenium.com.br
E-mail: sales@selenium-eu.com
E-mail: export@seleniu m-usa. com
URL: www.seleniumloud speaker s.com URL: www.seleniumloudsp eaker s.com
WOOFER
8W4P
8” Woofer with excellent performance in the mid frequency
ranges. Its great efficiency in sound reproduction is due excellent
combination of different components. This new design is capable
of handling up to 300 Watts Continous Music.
For sound reinforcement in nightclubs, dancing halls,
auditoriums, bands and also for studio monitors. Its great efficiency in
sound reproduction is due to the excellent combination of the different
components.
The epoxy painted reinforced steel frame provides the array with
high mechanical resistance, an impregnated fabric surround,
impregnated long fiber paper cone, give the array great stability, high
yield and low distortion.
The 8W4P woofer incorporates a magnetic assembly, of 147mm,
of high density of magnetic flux combined with the characteristics above
its check to the product high sensibility.
mm (in)
W
W
W
W
W
W
dB SPL
dB
dB
dB
Hz
THIELE-SMALL PARAMETERS
Fs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
Vas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.2 (0.32)
Qts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.70
Qes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.74
Qms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13.2
ho (half space) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.50
Sd. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.025 (38.75)
Vd (Sd x Xmax) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 (3.05)
Xmax (max. excursion (peak) with 10% distortion) . . . 2.0 (0.08)
Xlim (max.excursion (peak) before physical damage) . 16 (0.63)
%
m 2 (in 2)
cm 3 (in 3)
mm (in)
mm (in)
Atmospheric conditions at TS parameter measurements:
Temperature. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 (75)
Atmospheric pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1,020
Humidity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
°C (°F)
mb
%
Hz
l (ft3)
Thiele-Small parameters are measured after a 2-hour power test using half AES power .
A variation of ± 15% is allowed.
ADDITIONAL PARAMETERS
bL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.88
Flux density . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.08
Voice coil diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46 (1.81)
Voice coil winding length . . . . . . . . . . . . . . . . . . . . 14.1 (46.25)
Wire temperature coefficient of resistance (a25). . . . . 0.00342
Maximum voice coil operation temperature. . . . . . . . 200 (392)
qvc (max.voice coil operation temp./max.power) . . 1.33 (2.61)
Hvc (voice coil winding depth) . . . . . . . . . . . . . . . . . . 12 (0.47)
Hag (air gap height) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 (0.31)
Re . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 .2
Mms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20.2 (0.045)
Cms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 25
Rms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.008
NON-LINEAR PARAMETERS
Le @ Fs (voice coil inductance @ Fs) . . . . . . . . . . . . . . . 1.186
Le @ 1 kHz (voice coil inductance @ 1 kHz) . . . . . . . . . . 0.787
Le @ 20 kHz (voice coil inductance @ 20 kHz) . . . . . . . . 0.459
Red @ Fs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 .269
Red @ 1 kHz. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.861
Red @ 20 kHz . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23.753
Krm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 .1
Kxm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.8
Erm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.85
Exm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.82
Tm
T
mm (in)
m (ft)
1/°C
°C (°F)
°C/W(°F/W)
mm (in)
mm (in)
W
g (lb)
mm/N
kg/s
mH
mH
mH
W
W
W
mW
mH
ADDITIONAL INFORMATION
Magnet material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Barium ferrite
Magnet weight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1,240 (44) g (oz)
Magnet diameter x depth. . . . . . . . . . . . . . 147 x 18 (5.78 x 0.71) mm (in)
Magnetic assembly weight . . . . . . . . . . . . . . . . . . . . 3,200 (7.05) g (lb)
Frame material. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Steel
Frame finish . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Black epoxy
Voice coil material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Copper
Voice coil former material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Polyimide
Cone material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Long fiber pulp
Volume displaced by woofer. . . . . . . . . . . . . . . . . . . . . . . 2 (0.07) l (ft3)
Net weight. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3,600 (7.93) g (lb)
Gross weight. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3,800 (8.37) g (lb)
Carton dimensions (W x D x H) . . . . . 22.5 x 23 x 13.5 (8.85 x 9 x 5.3)
cm (in)
MOUNTING INFORMATION
Number of bolt-holes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Bolt-hole diameter . . . . . . . . . . . . . . . . . . . . . . 5 x 7 (0.19 x 0.27) mm (in)
Bolt-circle diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . 195 (7.67) mm (in)
Baffle cutout diameter (front mount). . . . . . . . . . . . . . . . 183 (7.2) mm (in)
Baffle cutout diameter (rear mount). . . . . . . . . . . . . . . 177 (6.96) mm (in)
Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Push on terminals
Polarity . . . . . . . . . . . . . . . . . . . . . . . . . . Positive voltage applied to the positive
terminal (red) gives forward cone motion
Minimum clearance between the back of the magnetic assembly and the
enclosure wall . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75 (3) mm (in)
ø 205
93
4x ø 5 x 7
ø 183
1
Power handling specifications refer to normal speech and/or music program material,
reproduced by an amplifier producing no more than 5% distortion. Power is calculated as
true RMS voltage squared divided by the nominal impedance of the loudspeaker.
2
NBR Standard (10,303 Brasilian Standard).
3
AES Standard (100 - 1000 Hz).
ø 195
ø 147
SPECIFICATIONS
Nominal diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205 (8)
Nominal impedance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Minimum impedance @ 325 Hz. . . . . . . . . . . . . . . . . . . . . . . 6.5
Power handling
Peak . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 600
Continous Music 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . 300
NBR2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 50
AES3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150
Sensitivity (2.83V@1m) averaged from 100 to 6,500 Hz . . . 96
Power compression @ 0 dB (nom. power) . . . . . . . . . . . . . . 3.7
Power compression @ -3 dB (nom. power)/2. . . . . . . . . . . . 2.6
Power compression @ -10 dB (nom. power)/10. . . . . . . . . . 1.1
Frequency response @ -10 dB . . . . . . . . . . . . . . . 100 to 6,500
34
50
8
Dimensions in mm.
WOOFER
8W4P
POLAR RESPONSE CURVES
RESPONSE CURVES (0° AND 45°) IN A TEST ENCLOSURE INSIDE AN
ANECHOIC CHAMBER, 1 W / 1 m
50 Hz
110
30°
105
95
100 Hz
300°
-20
dB
90°
30°
330°
-10
60°
100
0
-6
0
-6
250 Hz
330°
-10
60°
270° 90°
330°
-10
60°
300°
-20
dB
0
-6
30°
300°
-20
dB
270° 90°
270°
90
240°
dB
120°
85
150°
180°
240°
120°
210°
150°
330°
30°
180°
240°
120°
210°
150°
330°
30°
180°
210°
80
500 Hz
75
30°
70
60
100
200
500
Hz
1k
2k
5k
0
-6
1,25 kHz
-10
60°
-20
dB
270° 90°
330°
-10
60°
300°
0
-6
300°
-20
dB
270° 90°
270°
10k
240°
120°
Response Curve at 0°.
Response Curve at 45°.
150°
IMPEDANCE AND PHASE CURVES MEASURED IN FREE-AIR
180°
150°
330°
30°
80
60
300°
-20
dB
90°
30
240°
degrees
40
150°
180°
210°
0
-6
150°
30°
300°
-20
dB
240°
180°
0
-6
330°
-10
60°
300°
-20
dB
270° 90°
120°
150°
180°
210°
4 kHz
330°
-10
60°
270° 90°
120°
0
50
180°
240°
120°
210°
3,15 kHz
-10
60°
70
0
-6
240°
120°
210°
2 kHz
30°
60
90
ohms
300°
-20
dB
90°
50
800 Hz
-10
60°
65
0
-6
270°
240°
120°
210°
150°
180°
210°
Polar Response Curve.
30
20
10
50
100
200
500
1k
Hz
Impedance Curve.
Phase Curve.
HARMONIC DISTORTION CURVES MEASURED AT 10% AES INPUT
POWER, 1 m
110
FINDING VOICE COIL TEMPERATURE
It is very important to avoid maximum voice coil temperature. Since moving
coil resistance (RE) varies with temperature according to a well known law,
we can calculate the temperature inside the voice coil by measuring the
voice coil DC resistance:
æR
öæ
1
TB = TA + çç B - 1÷÷ çç TA - 25 +
a 25
è RA
øè
100
ö
÷÷
ø
TA , TB= voice coil temperatures in °C.
RA , RB= voice coil resistances at temperatures TA and TB, respectively.
a25= voice coil wire temperature coefficient at 25 °C.
90
80
dB
2k
HOW TO CHOOSE THE RIGHT AMPLIFIER
The power amplifier must be able to supply twice the RMS driver power. This
3 dB headroom is necessary to handle the peaks that are common to
musical programs. When the amplifier clips those peaks, high distortion
arises and this may damage the transducer due to excessive heat. The use
of compressors is a good practice to reduce music dynamics to safe levels.
POWER COMPRESSION
Voice coil resistance rises with temperature, which leads to efficiency
reduction. Therefore, if after doubling the applied electric power to the driver
we get a 2 dB rise in SPL instead of the expected 3 dB, we can say that
power compression equals 1 dB. An efficient cooling system to dissipate
voice coil heat is very important to reduce power compression.
70
60
50
40
30
102
Hz
Response Curve.
Distortion Curve, 2nd harmonic.
Distortion Curve, 3rd harmonic.
103
NON-LINEAR VOICE COIL PARAMETERS
Due to its close coupling with the magnetic assembly, the voice coil in
electrodynamic loudspeakers is a very non-linear circuit. Using the nonlinear modeling parameters Krm, Kxm, Erm and Exm from an empirical
model, we can calculate voice coil impedance with good accuracy.
SUGGESTED PROJECTS
For additional project suggestions, please access our website.
TEST ENCLOSURE
Closed box, with volume of 455 liters.
www.selenium.com.br
Devido aos avanços tecnológicos, reservamo-nos
o direito de inserir modificações sem prévio aviso.
Cód.: 28011062 Rev.: 00 - 01 / 06
www.seleniumloudspeakers.com
PROFESSIONAL LINE - Compression Driver
D210Ti
LOUDSPEAKERS
A high quality full range compression driver, is the
driver of choice for high performance, high value
professional systems. The titanium diaphragm assures high
sensitivity, low distortion and smooth, extended frequency
response.
It is highly recommended for use in monitor speakers,
stage monitors and surround speakers in movie theaters.
The following highlights the exceptional features of
the D210Ti:
- titanium dome diaphragm combining a stable
structure for mid-frequency reproduction with a low mass,
enabling outstanding high frequency reproduction up to
20 kHz;
- voice coil is made of high temperature wire wound
on Kapton® former to withstand high operating
temperatures;
- precisely engineered diaphragm structure and
alignment mechanism allows for easy, reliable and cost
effective repair in case of diaphragm failure.
DRIVER x HORN CONNECTION
SPECIFICATIONS
Nominal impedance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Ω
Minimum impedance @ 2,900 Hz . . . . . . . . . . . . . . . . . . . . . 7.3 Ω
Power handling
1
Musical Program (w/ xover 1,500 Hz 12 dB / oct) . . . 120 W
Musical Program (w/ xover 2,000 Hz 12 dB / oct)1 . . . 160 W
Sensitivity
On horn, 2.83V@1m, on axis 2 . . . . . . . . . . . . . . . . . . 107 dB SPL
Frequency response @ -06 dB . . . . . . . . . . . . . . 800 to 20,000 Hz
Throat diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 (1) mm (in)
Diaphragm material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Titanium
Voice coil diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 (1.7) mm (in)
Re . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.0 Ω
Flux density . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.6 T
Minimum recommended crossover (12 dB / oct) . . . . . . . 2,000 Hz
HL14-25
HM25-25
D210Ti
1
Power handling specifications refer to normal speech and/or music program material,
reproduced by an amplifier producing no more than 5% distortion. Power is calculated as
true RMS voltage squared divided by the nominal impedance of the loudspeaker. This
voltage is measured at the input of the recommended passive crossover when placed
between the power amplifier and loudspeaker.
Musical Program= 2 x W RMS.
2
Measured with HL14-25 horn, 1,200 - 15,000 Hz average.
ADDITIONAL INFORMATION
Magnet material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Barium ferrite
Magnet weight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 666 (23.5) g (oz)
Magnet diameter x depth. . . . . . . . . . . . . 115 x 15 (4.52 x 0.59) mm (in)
Magnetic assembly weight . . . . . . . . . . . . . . . . . . . 1666 (3.67) g (lb)
Housing material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Plastic
Housing finish. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Black
Magnetic assembly steel finish . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-Coating
Voice coil material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CCAW
®
Voice coil former material . . . . . . . . . . . . . . . . . . . . . . . . . Polyimide (Kapton )
Voice coil winding length. . . . . . . . . . . . . . . . . . . . . . 3.5 (11.48) m (ft)
Voice coil winding depth . . . . . . . . . . . . . . . . . . . . . . . 3.6 (0.14) mm (in)
Wire temperature coefficient of resistance (α25 ) . . . . . 0.00435 1/°C
3
Volume displaced by driver. . . . . . . . . . . . . . . . . . . . 0.5 ()0.017 l (ft )
Net weight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1,727 (3.80) g (lb)
Gross weight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1,812 (3.99) g (lb)
HM17-25
HM11-25
Ø115,0
53
19
MOUNTING INFORMATION
3
Horn connection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Screw-on 1 / 8” - 18 TPI
Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Push terminals
Polarity . . . . . . . . . . . . . . . . . Positive voltage applied to the positive terminal
(red) gives diaphragm motion toward the throat
Screw W - Ø 1 3
18 TPI.
Ø 25
72
Dimensions in mm.
Page: 1/1 Rev.: 00 - 12/02
PROFESSIONAL LINE - Compression Driver
D210Ti
LOUDSPEAKERS
RESPONSE AND IMPEDANCE CURVES W/ HL14-25 HORN INSIDE AN
ANECHOIC CHAMBER, 1 W / 1 m
120
25
110
20
100
15
HARMONIC DISTORTION CURVES W/ HL14-25 HORN, 5 W / 1 m.
140
120
100
90
10
80
5
80
0
70
200
500
1k
2k
Hz
5k
10k
20k
60
200
500
1k
2k
Hz
5k
10k
20k
Response Curve.
Distortion Curve, 2nd harmonic.
Distortion Curve, 3rd harmonic.
Response Curve.
Impedance Curve.
RESPONSE AND IMPEDANCE CURVES W/ PLANE-WAVE TUBE, 1 mW
1W 1mW
150 120
25
140 110
20
130 100
15
120
90
10
110
80
5
100
70
0
200
500
1k
2k
Hz
5k
10k
20k
Response Curve.
Impedance Curve.
Frequency response and impedance curves measured with 25 mm
terminated plane-wave tube.
HARMONIC DISTORTION CURVES W/ HL14-25 HORN, 1 W / 1 m.
120
HOW TO CHOOSE THE RIGHT AMPLIFIER
The power amplifier must be able to supply twice the RMS driver power. This
3 dB headroom is necessary to handle the peaks that are common to
musical programs. When the amplifier clips those peaks, high distortion
arises and this may damage the transducer due to excessive heat. The use
of compressors is a good practice to reduce music dynamics to safe levels.
100
80
FINDING VOICE COIL TEMPERATURE
It is very important to avoid maximum voice coil temperature. Since moving
coil resistance (RE) varies with temperature according to a well known law,
we can calculate the temperature inside the voice coil by measuring the
voice coil DC resistance:
60
R

1
TB = TA +  B − 1  TA − 25 +
α 25
 RA

40
200
500
1k
2k
Hz
Response Curve.
Distortion Curve, 2nd harmonic.
Distortion Curve, 3rd harmonic.
5k
10k
20k



TA , T B= voice coil temperatures in °C.
R A , RB= voice coil resistances at temperatures T A and TB, respectively.
α25= voice coil wire temperature coefficient at 25 °C.
®
Kapton : Du Pont trademark.
Ferrosound ® : Ferrofluidics Corporation trademark.
Specifications subject to
change without prior notice.
Page: 2/2 Rev.: 00 - 12/02
EUROPE Adress:
SELENIUM EUROPE
Germany
www.seleniumloudspeakers.com
USA Adress:
SELENIUM USA
USA
www.seleniumloudspeakers.com
BRAZIL Address:
ELETRÔNICA SELENIUM S.A.
BR 386 Km 435 / 92.480-000
Nova Santa Rita - RS - Brazil
Fax: +(55) 51 479-1120
www.selenium.com.br
PROFESSIONAL LINE - Driver
DH200E
LOUDSPEAKERS
The DH200E driver has a titanium diaphragm carefully
designed to cover the frequency range from midrange to
treble with high efficiency and low distortion.
This astonishing performance was achieved using
titanium, a light and strong space age material that allows
frequency reproduction from 1.5 to 20 kHz. This way,
compact two-way systems can be designed for use as
stage monitors, movie theatre systems and home theatre
sound reproduction.
The driver must be used with active or passive
crossover with crossover frequencies of 2 kHz or higher
and a slope of at least 12 dB/oct. We suggest the Selenium
passive crossover LC12M2K8 (2,000 Hz - 12 dB/oct).
The voice coil is made of high temperature wire
wound on Kapton ® former to withstand high operating
temperatures.
A precisely engineered diaphragm structure and
alignment mechanism allows for easy, reliable and cost
effective repair in case of diaphragm failure.
DRIVER x HORN CONNECTION
HM17-25E
SPECIFICATIONS
Nominal impedance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Ω
Minimum impedance @ 4,250 H z . . . . . . . . . . . . . . . . . . . . . 6.9 Ω
Power handling
Musical Program(w/ xover 2,000 Hz 12 dB / oct) 1. . . 200 W
Sensitivity
2
On horn,1W @ 1m, on axis . . . . . . . . . . . . . . . . . . . . 105 dB SPL
Frequency response @ -10 dB. . . . . . . . . . . . . 1,500 to 20,000 Hz
Throat diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 (1) mm (in)
Diaphragm material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Titanium
Voice coil diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46 (1.8) mm (in)
Re . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.8 Ω
Flux density . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.55 T
Minimum recommended crossover (12 dB / oct) . . . . . . . 2,000 Hz
HM11-25
DH200E
HM25-25
1
Specifications to handle normal speech and music program material with 5% maximum
acceptable distortion on amplifier, with the recommended passive crossover connected.
Power is calculated taking into account the true RMS voltage at amplifier output along
with transducer nominal impedance.
Musical Program= 2 x W RMS.
2
Measured with HM17-25E horn, 1,500 - 8,000 Hz average.
ADDITIONAL INFORMATION
Magnet material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Barium ferrite
Magnet weight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 429 (15) g (oz)
Magnet diameter x depth . . . . . . . . . . . . . . 102 x 14 (4.02 x 0.55) mm(in)
Magnetic assembly weight . . . . . . . . . . . . . . . . . . . . 1,200 (2.65) g (lb)
Housing material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Plastic
Housing finish . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Black
Magnetic assembly steel finish . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Zinc-plated
Voice coil material. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Copper
Voice coil former material . . . . . . . . . . . . . . . . . . . . . . . . . Polyimide (Kapton® )
Voice coil winding length. . . . . . . . . . . . . . . . . . . . . . . 2.8 (9.19) m (ft)
Voice coil winding depth . . . . . . . . . . . . . . . . . . . . . . . 2.2 (0.09) mm (in)
Wire temperature coefficient of resistance (α25) . . . . . 0.00380 1/°C
Volume displaced by driver . . . . . . . . . . . . . . . . . . . . . 0.4 (0.014) l (ft 3)
Net weight (1 piece). . . . . . . . . . . . . . . . . . . . . . . . . . 1,350 (2.98) g (lb)
Gross weight (6 pieces per carton). . . . . . . . . . . . . 8,400 (18.52) g (lb)
Carton dimensions (W x D x H) . . . . . . . . 35.5 x 24 x 9 (14 x 9.5 x 3.5)
c m (in)
MOUNTING INFORMATION
Horn connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Screw-on 1 3/8” - 18 TPI
Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Push terminals
Polarity . . . . . . . . . . . . . . . . . . . Positive voltage applied to the positive terminal
(red) gives diaphragm motion toward the throat
Page: 1/2 Ed.: 00 - 04/01
HL14-25
ø 102
70
W1 3/8" - 18TPI
ø 25
55
15
Dimensions in mm.
PROFESSIONAL LINE - Driver
DH200E
LOUDSPEAKERS
HARMONIC DISTORTION CURVES W / HM17-25E HORN, 10 W / 1 m.
RESPONSE CURVE W/ HM17-25E HORN INSIDE AN ANECHOIC
CHAMBER, 1 W / 1 m
120
140
110
120
100
100
90
80
80
70
200
500
1k
2k
Hz
5k
10k
60
20k
200
Response Curve.
500
1k
2k
Hz
5k
10k
20k
Response Curve.
Distortion Curve, 2nd harmonic.
Distortion Curve, 3rd harmonic.
IMPEDANCE AND PHASE CURVES MEASURED W/ HM17-25E HORN
IN FREE-AIR.
15
30
POLAR RESPONSE CURVES
1 kHz
30°
15
10
0
-6
2 kHz
330°
-10
60°
300°
-20
dB
90°
0
240°
150°
180°
210°
0
-6
4 kHz
330°
-10
60°
30°
240°
150°
180°
330°
300°
-20
dB
270° 90°
120°
0
-6
-10
60°
300°
-20
dB
270° 90°
120°
5
30°
270°
240°
120°
210°
150°
180°
210°
8 kHz
0
30°
-15
200
500
1k
2k
Hz
5k
10k
20k
Impedance Curve.
Phase Curve.
0
-6
330°
-10
60°
300°
-20
dB
90°
240°
120°
HARMONIC DISTORTION CURVES W/ HM17-25E HORN , 1 W / 1 m.
120
DH200E driver
coupled to a
HM17-25E h orn.
270°
150°
180°
210°
Polar Response Curve, Horizontal.
Polar Response Curve, Vertical.
100
HOW TO CHOOSE THE RIGHT AMPLIFIER
The power amplifier must be able to supply twice the RMS driver power. This
3 dB headroom is necessary to handle the peaks that are common to
musical programs. When the amplifier clips those peaks, high distortion
arises and this may damage the transducer due to excessive heat. The use
of compressors is a good practice to reduce music dynamics to safe levels.
80
60
40
200
500
1k
Response Curve.
Distortion Curve, 2nd harmonic.
Distortion Curve, 3rd harmonic.
®
Kapton : Du Pont trademark.
Specifications subject to
change without prior notice.
Page: 2/2 Ed.: 00 - 04/01
2k
Hz
5k
10k
20k
FINDING VOICE COIL TEMPERATURE
It is very important to avoid maximum voice coil temperature. Since moving
coil resistance (RE ) varies with temperature according to a well known law,
we can calculate the temperature inside the voice coil by measuring the
voice coil DC resistance:
R

1
TB = TA +  B − 1  TA − 25 +
α 25
 RA




T A , TB= voice coil temperatures in °C.
R A , RB= voice coil resistances at temperatures T A and TB, respectively.
α25= voice coil wire temperature coefficient at 25 °C.
EUROPE Address:
BRAZIL Address:
USA Address:
SELENIUM EUROPE
ELETRÔNICA SELENIUM S.A.
SELENIUM LOUDSPEAKER USA
BR 386 Km 435 / 92.480-000
Rohrbergstrasse 23B
1701 South Park Court, Bldg 102
D-65343 Eltville - Germany
Chesapeake, VA 23320 - USA
Nova Santa Rita - RS - Brazil
Phone: +(49) 6123 601570
Phone: (757) 424-7516 / (800) 562-0510
Fax: +(55) 51 479-1120
Fax: +(49) 6123 601587
URL: www.selenium.com.br
Fax: (757) 424-5246
E-mail: sales@selenium-eu.com
E-mail: export@selenium-usa.com
URL: www.seleniumloudspeakers.com URL: www.seleniumloudspeakers.com
Pro Sound
Speakers, Drivers & Horns
B&C High Frequency Horns
B&C Speakers produces a series of horns for compression drivers ranging from constant directivity models—
known for their great consistency in angular coverage — to exponential models, which optimize acoustical
loading and sound energy transfer. Standardized driver mounting flanges give the designer the freedom to
choose the best horn/driver combination for each project.
#294-618
#294-620
#294-622
Part #
Mfg. #
Horn Type
Min
Freq
294-618
294-620
294-622
294-624
294-626
ME10
ME15
ME45
ME60
ME90
Hyperbolic Cosine ABS
Exponential Cast Aluminum
Exponential Cast Aluminum
Constant Directivity Cast Aluminum
Constant Directivity Cast Aluminum
1.5 kHz
1.5 kHz
1 kHz
800 Hz
900 Hz
Nominal
Dispersion
90º
90º
90º
90º
80º
H
H
H
H
H
x
x
x
x
x
60º
60º
40º
40º
60º
#294-624
Throat
Dia.
V
V
V
V
V
Mounting
Type
1"
1"
1"
2"
1.4"
2
2
2
4
4
bolt
bolt
bolt
bolt
bolt
#294-626
Dimensions
(W x H x D)
Price
(1-3)
Price
(4-UP)
5.1" x 5.1" x 3.5"
5.4" x 5.9" x 3.5"
5.6" x 12.2" x 4.9"
9.3" x 10.6" x 7.9"
10.6" x 10.6" x 5.5"
$15.25
26.84
44.15
82.88
71.48
$13.80
24.65
41.80
77.25
66.90
Eminence Professional Horns
All Eminence horns are constructed of a high-density, heavy-duty, injection molded ABS. The TI2000 was
designed to support even the largest 4-bolt horn driver without the need for extra support brackets.
#290-558
#290-556
#290-550
#290-552
Part #
Mfg. #
Horn Type
Min
Freq
Nominal
Dispersion
Throat
Dia.
290-558
290-556
290-550
290-552
290-554
290-560
LT250
SST1
H295
H395
H290
TI2000
Constant Directivity
Constant Directivity
Constant Directivity
Constant Directivity
Bi-radial
Directivity, Radial
1 kHz
1 kHz
1 kHz
1 kHz
1 kHz
500 Hz
80º H x 60º V
90º H x 40º V
90v H x 40º V
90º H x 40º V
90º H x 40º V
60º H x 40º V
1"
1"
1"
1"
1"
2"
Mounting
Type
2
2
2
2
2
4
bolt/3
bolt/3
bolt/3
bolt/3
bolt/3
bolt
#290-560
#290-554
bolt
bolt
bolt
bolt
bolt
Dimensions
(W x H x D)
List
Price
Price
Each
6.7" x 6.4" x 3.8"
9.8" x 7.7" x 5.2"
12.1" x 6" x 4"
15.6" x 7.3" x 6.1"
11.4" x 6.5" x 5.9"
11.1" x 9.6" x 10"
$29.99
34.99
34.99
39.99
39.99
69.99
$24.97
29.97
29.97
34.97
34.97
64.97
Mounting type notes: 2 hole- For 2 x 1/4"-20; 3" o.c. mount drivers, 3 hole- For 3 x M6, 2.25" o.c. mount drivers; 4 hole- For 4 x 1/4"-20, 4" o.c. mount drivers.
Metallized Polypropylene Capacitors
•
•
•
•
•
250 VDC
10% tolerance
High purity
High current capacity
Specially designed for
crossovers
The Dayton metallized polypropylene capacitors are
ideal for use in loudspeaker crossover networks.
When using them as blocking caps in multi-amped
systems, select a cap value that provides a 6 dB/
octave crossover about one octave below the actual
active crossover point.
Approximate 8
ohm/6 dB per octave
blocking caps
Frequency
Value
800 Hz
1,000 Hz
1,600 Hz
2,000 Hz
3,000 Hz
5,000 Hz
25 uF
20 uF
12 uF
10 uF
6 uF
4 uF
Double capacitance
for 4 ohm loads,
halve for 16 ohm
loads
parts-express.com
Part #
Value
Dimensions
Dia x L (mm)
Price
(1-9)
Price
(10-99)
027-420
027-421
027-422
027-425
027-424
027-426
027-428
027-430
027-432
027-434
027-436
027-438
027-440
027-442
3.3 uF
4.0 uF
4.7 uF
5.6 uF
6.8 uF
8.2 uF
10.0 uF
12.0 uF
15.0 uF
18.0 uF
20.0 uF
25.0 uF
30.0 uF
40.0 uF
17.5 x 31
17.8 x 31
21 x 32
21.5 x 31
19.5 x 46
21.5 x 46
22 x 46
22.5 x 56
25 x 56
28 x 56
28.5 x 56
30 x 61
32 x 61
40.5 x 61
$1.69
1.92
2.13
2.27
2.53
2.93
3.75
4.34
5.23
5.37
5.77
6.58
8.52
10.24
$1.61
1.83
2.03
2.16
2.41
2.79
3.57
4.14
4.98
5.12
5.50
6.27
8.11
9.75
Complete list of capacitors on pages 161-163
235
Pro Sound
Speakers, Drivers & Horns
See page 228-233 for our selection of
compatible horn drivers.
Horn Lenses
These molded horn lenses are constructed of high-impact ABS and feature the standard 1-3/8"-18 TPI screw-on driver mounting threads. Some
models feature a metal thread insert for added durability. Note: The depth listed in dimensions is mounting depth, without driver, and not
necessarily the overall depth of the lens. Horn drivers sold separately.
#270-096
#270-095
Dimensions
Part #
Width
Height
Depth
270-092
270-095
270-096
260-090
270-099
7-11/16"
10-7/16"
12"
13-7/8"
15-3/16"
#270-099
#260-090
#270-092
6-1/8"
4-7/8"
4-1/2"
6-15/16"
5-1/8"
4-3/8"
6-3/4"
5"
7-15/16"
6"
Hole Cutout
Width
Height
6-1/4"
9-1/4"
10-3/4"
12-3/4"
13-5/8"
4-5/8"
3-1/4"
3-1/4"
5-5/8"
3-3/4"
Metal
Threads
Price
(1-3)
Price
(4-19)
Price
(20-UP)
No
No
No
Yes
Yes
$3.90
5.50
5.50
12.94
10.35
$3.50
5.10
5.10
11.65
8.90
$2.90
4.80
4.80
10.15
7.10
Dayton Professional High Frequency Horns
Dayton Professional horns are engineered to operate smoothly down to
the lowest possible crossover frequency, while maintaining consistent and
predictable dispersion throughout their intended range. The mediumformat constant directivity H110 is intended for large PA cabinets, and its
symmetrical mouth permits easy rotation when used in multi-application
enclosures. The small-format constant directivity H612 will give great
perfor­mance in short-throw, wide dispersion situations, while the slightly
larger H812 employs a traditional exponential flare which provides
improved throw and better HF response, but with narrowing dispersion
at the highest frequencies. All three horns are precision molded from
glass-reinforced polycarbonate. The H812 is designed for two-bolt 1" exit
drivers, while the H110 and H812 have threaded brass 1-3/8" x 18 TPI
throats for screw-on style drivers.
Part#
Mfg. #
270-300
270-302
270-304
H110
H612
H812
#270-304
#270-302
#270-300
Driver
Mounting
Lowest Rec.
Xover Freq.
Nominal
Conversion
Dimensions
(H x W x D)
List
Price
Price
(1-3)
Price
(4-UP)
1-3/8" x 18 TPI
1-3/8" x 18 TPI
1" bolt-on
700 Hz
1,200 Hz
800 Hz
90º H x 40º V
100º H x 50º V
100º H x 60º V
11-1/2" x 11-1/2" x 9-5/8"
6-1/4" x 12-3/4" x 4-1/8"
7-7/8" x 12-1/2" x 8-1/8"
$24.99
13.99
24.99
$19.29
10.56
19.21
$17.53
9.60
17.47
Dayton Professional High Frequency
Waveguides
A waveguide couples the high frequency driver to the listening
space without the harmful distortion artifacts of marginally designed
and implemented horn loading. It achieves this through the use of
non-traditional geometries and lower expansion rates. The resultant
sound has less distortion, with an “open” characteristic not often
associated with typical “pinched” or “honky” compression driver/
horn combinations. Dayton Professional waveguides reveal all of
the articulate, accurate sound reproduction that your HF drivers
are capable of delivering, whether the application is live sound,
critical studio monitoring, or demanding home audio playback. Two
versions are available, round or elliptical. Both are precision molded
from high-performance plastic, and have industry-standard 1-3/8" x
18 TPI throats for screw-on style drivers.
Part#
Mfg. #
Shape
270-306
270-308
270-310
270-312
270-314
270-316
236
H06RW
H08RW
H10RW
H12RW
H45E
H07E
Round
Round
Round
Round
Elliptical
Elliptical
Lowest Rec.
Xover Freq.
2,500
2,200
1,600
1,200
3,500
2,200
Hz
Hz
Hz
Hz
Hz
Hz
#270-306
#270-308
#270-310
#270-312
#270-316
Nominal
Conversion
75º
75º
75º
75º
80º
80º
conical
conical
conical
conical
H x 50˚ V
H x 50˚ V
#270-314
Dimensions
(H x W x D)
List
Price
Price
(1-3)
Price
(4-UP)
5-7/8" round x 4" D
8" round x 4-3/4" D
10" round x 5" D
11-1/2" round x 5-1/4" D
4-11/16" x 4-5/8" x 3-1/8"
7" x 7-1/8" x 3-5/8"
$5.99
6.99
9.99
13.99
5.99
8.99
$4.37
4.77
7.60
9.47
4.40
6.23
$3.97
4.34
6.91
8.61
4.00
5.67
1-800-338-0531
Revised Design
After researching more reputable driver manufactures’ online and reading a number of reviews I
developed a revised design with hopes of better reaching my initial goals. The Eminence woofers are
very appealing because of their decent reputation and high sensitivity. Interestingly enough the 8” and
the 10” have similar high end compatibles and the 10” even has a more even response overall. Even at a
10” size, the woofer was only recommended for “mid-bass” and couldn’t extend very far below 70Hz. I
really felt the pull from all directions in an economic battle between cost, sensitivity, and frequency
response. At this point I thought I was doing very well in terms of SPL capability and my budget was still
healthy however I still wasn’t truly satisfied with the low end response. This design probably would
have done a sufficient job of meeting the majority of the requirements especially with the option if
introducing a stand-alone subwoofer had the bass response been really terrible. Nonetheless, I’m
grateful I was able to develop an even better design that would make this proposal obsolete.
Eminence ALPHA-10A | 4th Order Vented Enclosure
Eminence ALPHA-10A | 2nd Order Sealed Enclosure (Manufacturer Recommended)
Specification
Nominal Basket Diameter
Nominal Impedance*
Power Rating**
Resonance
Usable Frequency Range
Sensitivity***
Magnet Weight
Gap Height
Voice Coil Diameter
10”, 254mm
8 ohms
150W
50Hz
57Hz-4.5kHz
95.6
20 oz.
0.25”, 6.35mm
1.5”, 38.1mm
The Art and Science of Sound
Thiele & Small Parameters
Resonant Frequency (fs)
DC Resistance (Re)
Coil Inductance (Le)
Mechanical Q (Qms)
Electromagnetic Q (Qes)
Total Q (Qts)
Compliance Equivalent Volume (Vas)
Peak Diaphragm Displacement Volume (Vd)
Mechanical Compliance of Suspension (Cms)
BL Product (BL)
Diaphragm Mass inc. Airload (Mms)
Efficiency Bandwidth Product (EBP)
Maximum Linear Excursion (Xmax)
Surface Area of Cone (Sd)
Maximum Mechanical Limit (Xlim)
50Hz
5.31
0.66mH
5.21
0.66
0.59
82.2 liters / 2.9 cu. ft.
114cc
0.46mm/N
7.5 T-M
22 grams
76
3.2mm
355.4 cm2
9.1mm
ALPHA-10A
American Standard Series
Recommended for professional audio mid-bass applications in a small sealed cabinet.
Mounting Information
Recommended Enclosure Volume
Sealed
Vented
Overall Diameter
Baffle Hole Diameter
Front Sealing Gasket
Rear Sealing Gasket
Mounting Holes Diameter
Mounting Holes B.C.D.
Depth
Net Weight
Shipping Weight
8.5-11.3 liters/0.3-0.4 cu.ft.
28.3-53.8 liters/1.0-1.9 cu.ft.
10.11”, 256.8mm
9.13”, 231.8mm
fitted as standard
fitted as standard
0.23”, 5.7mm
9.6”, 243.8mm
3.90”, 99mm
4.5 lbs., 2 kg
5.6 lbs., 2.5 kg
Materials of Construction
Copper voice coil
Polyimide former
Ferrite magnet
Vented and extended core
Pressed steel basket
Paper Cone
Cloth cone edge
Solid composition paper dust cap
* Please inquire about alternative impedances.
** Multiple units exceed published rating evaluated under EIA 426A noise source and test standard while in a free-air, non-temperature controlled environment.
*** The average output across the usable frequency range when applying 1W/1M into the nominal impedance. Ie: 2.83V/8ohms, 4V/16ohms.
Eminence response curves are measured under the following conditions: All speakers are tested at 1w/1m using a variety of test set-ups for the appropriate impedance | LMS using 0.25” supplied microphone (software
calibrated) mounted 1m from wall/baffle | 2ft. X 2ft. baffle is built into the wall with the speaker mounted flush against a steel ring for minimum diffraction | Hafler P1500 Trans-Nova amplifier | 2700 cu.ft. chamber with
fiberglass on all six surfaces (three with custom-made wedges)
Specification
Nominal Basket Diameter
Nominal Impedance*
Power Rating**
Resonance
Usable Frequency Range
Sensitivity***
Magnet Weight
Gap Height
Voice Coil Diameter
8”, 203.2mm
8 ohms
125W
73Hz
58Hz-5kHz
94
20 oz.
0.25”, 6.35mm
1.5”, 38.1mm
The Art and Science of Sound
Thiele & Small Parameters
Resonant Frequency (fs)
DC Resistance (Re)
Coil Inductance (Le)
Mechanical Q (Qms)
Electromagnetic Q (Qes)
Total Q (Qts)
Compliance Equivalent Volume (Vas)
Peak Diaphragm Displacement Volume (Vd)
Mechanical Compliance of Suspension (Cms)
BL Product (BL)
Diaphragm Mass inc. Airload (Mms)
Efficiency Bandwidth Product (EBP)
Maximum Linear Excursion (Xmax)
Surface Area of Cone (Sd)
Maximum Mechanical Limit (Xlim)
73Hz
5.3
0.44mH
4.6
0.68
0.59
17.7 liters / 0.6 cu.ft.
67cc
0.28mm/N
7.8 T-M
17 grams
107
3.2mm
210.0 cm2
7.1mm
ALPHA-8A
American Standard Series
Recommended for professional audio mid-range applications in a sealed cabinet, or as a mid-bass in a vented
satellite enclosure.
Mounting Information
Recommended Enclosure Volume
Sealed
Vented
Overall Diameter
Baffle Hole Diameter
Front Sealing Gasket
Rear Sealing Gasket
Mounting Holes Diameter
Mounting Holes B.C.D.
Depth
Net Weight
Shipping Weight
5-7 liters/0.18-0.25 cu.ft.
16.7-25.5 liters/0.59-0.90 cu.ft.
8.24”, 209.2mm
7.13”, 181mm
fitted as standard
fitted as standard
0.22”, 5.5mm
7.75”, 196.9mm
3.25”, 83mm
4.3 lbs., 1.9 kg
5.1 lbs., 2.3 kg
Materials of Construction
Copper voice coil
Polyimide former
Ferrite magnet
Vented core
Pressed steel basket
Paper Cone
Cloth cone edge
Solid composition paper dust cap
* Please inquire about alternative impedances.
** Multiple units exceed published rating evaluated under EIA 426A noise source and test standard while in a free-air, non-temperature controlled environment.
*** The average output across the usable frequency range when applying 1W/1M into the nominal impedance. Ie: 2.83V/8ohms, 4V/16ohms.
Eminence response curves are measured under the following conditions: All speakers are tested at 1w/1m using a variety of test set-ups for the appropriate impedance | LMS using 0.25” supplied microphone (software
calibrated) mounted 1m from wall/baffle | 2ft. X 2ft. baffle is built into the wall with the speaker mounted flush against a steel ring for minimum diffraction | Hafler P1500 Trans-Nova amplifier | 2700 cu.ft. chamber with
fiberglass on all six surfaces (three with custom-made wedges)
COMPRESSION DRIVER PSD:2002
For all bass applications. oooooooooooooooooo
Throat Size
Impedance
Power Ratings:
(EIA426B specification, 1.6kHz @ 18dB)
Resonance
Usable Frequency Range
Sensitivity (1W @1m on axis on horn)
Magnet Weight
Voice Coil Diameter
Voice Coil Former
Diaphragm Material
1", 25.4mm
8Ω or 16Ω
80Wrms
550Hz
1.5Hz - 20kHz
105dB
34oz.
2", 51mm
DuPont Kapton
Titanium
Mounting Information
The 1" throat Eminence compression drivers are available in either
a bolt-on (PSD:2002) or screw-on (PSD:2002S) format.
Overall Diameter
Depth
Mounting Holes Diameter (PSD:2002)
Mounting Holes B.C.D.
Mounting Thread (PSD:2002S)
5.25", 133mm
2.2", 56mm
2X 1/4-20 on 3" BHC
3X M6 on 2.25" BHC
1 3/8" 18 NEF ext.
COMPRESSION DRIVER PSD:2002S
file:///C|/Documents%20and%20Settings/charlotte.b.../Eminence/pages/products02/specsheets/psd2002.htm (2 of 2) [5/30/2002 9:42:48 AM]
Horns
DE 10 | Hf Compression drivers
1" high frequency compression driver. Low mass mylar
diaphragm and optimized ceramic magnet assembly allows
high sensitivity and low distortion up to 18 kHz.
Speakers
HPL
Coaxials
HF Compression drivers
Specifications1
Throat Diameter
Nominal Impedance
Minimum Impedance
Power Handling
(2500 –20000 Hz)
Nominal2
Continuous Program3
Sensitivity (1W/1m)4
Frequency Range
Recommended crossover5
Voice Coil Diameter
Winding Material
Inductance
Diaphragm Material
Flux Density
25 mm (1 in)
8Ω
6.3 Ω
20 W
40 W
107 dB
1.5 – 18 kHz
2.5 kHz
25 mm (1 in)
Aluminium
0.1 mH
Mylar
1.55 T
Mounting and Shipping Information
Two M5 holes 180° on 76 mm (3 in) diameter
Overall Diameter
90 mm (4.4 in)
Depth
53 mm (2.1 in)
Net weight (1 unit)
0.8 kg (1.8 lb)
Shipping Weight (8 units)
6.7 kg (14.7 lb)
Shipping Box (8 units)
220x220x150 mm
(8.7x8.7x5.9 in)
1
Driver mounted on B&C ME 10 horn.
2 hours test made with continuous pink noise signal (6 dB crest factor) within
the specified range. Power calculated on rated minimum impedance.
3
Power on Continuous Program is defined as 3 dB greater than the Nominal rating.
4
Applied RMS Voltage is set to 2.83V for 8 ohms Nominal Impedance. Average
SPL from 2000 to 18000 Hz.
5
12 dB/oct. or higher slope high-pass filter.
2
Final Design
In terms of design innovation, perhaps the best class period I had all semester was the one and
only I didn’t attend. On a road trip through Madison, Wisconsin I had the privilege of meeting Adam
Johnson of Madisound Speaker Components who inspired my final design. The high sensitivity woofers I
had considered in past designs lacked the fidelity that was really desired for this system. At the budget
given, a three-way system was quite out of the question although it would work nicely for the SPL and
bass desired. To resolve this issue the “woofer-tweeter-woofer” configuration was suggested. The
summing of two high quality (but less sensitive) woofers bridges the gap between sensitivity and
frequency response. Although there is an additional driver to contribute to the cost the system is still a
2-way so there aren’t any additional crossover parts to increase the overall as in a 3-way system. The
driver budget was now being pushed to the limit; moreover, I had a design that boasted high SPL
outputs, excellent low end extension down to around 40 Hz at F(-3dB), and drivers from very reputable
manufacturers. Having the true feeling of innovation and a unique design that best met the given
requirements, I knew I was ready move forward with this design.
MDT 37
Soft Dome Horn Tweeter
• Large diameter Hexatech aluminium voice coil
• Ferro fluid cooled
• High power handling
• High max. SPL of 116dB nom.
• Replaceable dome/coil assembly
• Sturdy gold-plated input tags
• Injected polymer faceplate
SPECIFICATIONS
Overall Dimensions
Nominal Power Handling (DIN)
OD 94mm (3.7") x 58mm (2.28")
P
200 W (116dB)
Z
8 Ohms
Transient Power 10ms
Nominal Impedance
1000 W
Sensitivity 1W/1M
93 dB
Frequency Response
1800 - 22000 Hz
Resonant Frequency
FS
700 Hz
VOICE COIL
Voice Coil Diameter
28mm (1.1")
Voice Coil Height
2.7mm (0.106")
Voice Coil Former
Aluminium
Voice Coil Wire
Hexatech Aluminium
Number of Layers
2
DC Resistance
RE
5.2 Ohms
Voice Coil Inductance @ 1KHz
LBM
0.09 mH
HE - Magnetic Gap Height
HE
2.5mm (0.098")
B Flux density
B
1.5T
BL Product
BXL
3.5 tm
Max. Linear Excursion
X
MAGNET SYSTEM
Magnet System Type
Ferrite Vented
OPERATIONAL PARAMETERS
Moving Mass
MMS
0.44 gm.
Effective Piston Area
S
6.0 cm²
Net Weight
Kg.
0.56 Kg.
Cone / Dome Material
Hand Treated Selected Fabric
This very high efficiency and rigid built tweeter is an improved version of the well-established and highly regarded MDT 27. A new horn facia, less
deep and optimised for his purpose make this one even better. A better off axis response, improved dispersion and 3dB higher sensitivity above 5kHz
are the results as well as a very flat frequency response curve. The damped rear chamber lowers the resonant frequency and smoothens the
impedance curve. The ferro fluid, Hexatech aluminium voice coil let this special tweeter handle a tremendous power and provides high efficiency
systems with a crystal clear and clean, dynamic sound. Quick service by self-centring dome assembly and very high SPL make this tweeter a perfect
match for very high quality PA-systems as well as for high efficiency horn systems.
www.moreleurope.com
Peerless Data Sheet - ID: 830668
1 of 2
http://www.tymphany.com/peerless/data/830668.htm
print close drawing application
Peerless Data Sheet
Type: SLS
263 SWR 39 115 THSX AL 4L 8 OHM - 830668
Electrical data
Nominal impedance
Minimum imp./at freq.
Maximum impedance
Dc resistance
Voice coil inductance
Zn
Zmin
Zo
Re
Le
TS Parameters
Resonance Frequency
Mechanical Q factor
Electrical Q factor
Total Q factor
fs
Qms
Qes
Qts
33.3 (Hz)
4.85
0.57
0.51
Bl
Rms
Mms
Cms
D
Sd
Vas
10.2
2.2
51.1
0.45
20.7
335
69.3
88.7
Force factor
Mechanical resistance
Moving mass
Suspens. compliance
Effective cone diam.
Effective piston area
Equivalent volume
SPL 2.83V/1m at fmin
8
6.3/126
53.2
5.6
3.3
Power handling
100h RMS noise test (IEC)
Longterm Max System Power (IEC)
IEC268-5 noise signal is used for the powertest.
(ohm)
(ohm/Hz)
(ohm)
(ohm)
(mH)
(Tm)
(Kg/s)
(g)
(mm/N)
(cm)
(cm²)
(ltrs)
(dB)
- (W)
- (W)
Voice coil and magnet parameters
Voice coil diameter
Voice coil length
Voice coil layers
Height of the gap
Linear excursion +/Max mech. excursion +/Total useful flux
Diameter of magnet
Height of magnet
Weight of magnet
Factors
Ratio fs/Qts
Ratio BL/sqrt(Re)
39.0 (mm)
24.0 (mm)
4
8.0 (mm)
8.0 (mm)
- (mm)
1.3 (mWb)
115 (mm)
22 (mm)
0.87 (kg)
65
4.3
Special remarks
-
Remarks on powertest
-
10/03/2005 10:01 AM
Peerless Data Sheet - ID: 830668
2 of 2
http://www.tymphany.com/peerless/data/830668.htm
Measuring methods and conditions are stated in Peerless Standard for Acoustic Measurements (PSAM)
10/03/2005 10:01 AM
SLS PLATFORM
1 of 2
http://www.tymphany.com/papers/sls_intro.htm
SLS PLATFORM
A new class of midbass and subbass drivers from Peerless.
With the new SLS platform design, Peerless have incorporated many of the features from the highly regarded XLS
subwoofer platform. A variety of different cone technologies will be available for the SLS platform.
Furthermore a PA cone for high SPL is available. The SLS platform is available in sizes 8" and 12".
A. Low profile of basket
The low profile front of the basket is chamfered so that no countersinking is necessary. For rear mounting a rigid
cardboard gasket can be fitted.
B. Rubber surround
For maximum durability and quality, the SLS subwoofer cones are fitted with rubber surrounds. For other applications
cloth or foam surrounds are a possibility.
C. Various cones
For customization of sound Peerless is able to supply cones in different configurations. The cost effective pressed and
coated paper cone with foam surround will give a crisp and forward sound, with a lean dry bass reproduction. The
air-dried cone with rubber surround reproduces an even more rich bass sound.
D. Large dustcap
The large dustcap results in a "potent" look and leaves a very good printable platform for customization of the product.
E. Soft roll spider
The flat soft roll spider supports the cone movement and allows for more than ±18mm ( 0.8" ) of cone travel. For
maximum durability and a long lifetime, a carefully blended mix of cotton and Nomex® has been chosen.
F. Aluminum or kapton voice coil
The 39 mm aluminum voice coil former ensures a very good heat dissipation of the voice coil during high power loads and
reduces power compression. The high temperature wire stays in position even when temperature reaches 250°C ( 482°F).
For special applications where high mechanical Q is needed, a Kapton® or Kapton®MTB voice coil former is available.
G. Undercut polepiece
The polepiece is undercut to allow for more cone travel without noise. The undercut also improves linearity, resulting in
low distortion.
H. Vented pole piece
The pole piece has a very large bore leaving just the necessary steel for the magnetic flux. The result of this is very low
compression. The bore has flared ends for quiet cooling.
12/15/2007 3:40 PM
SLS PLATFORM
2 of 2
http://www.tymphany.com/papers/sls_intro.htm
I. Extended backplate
The deeply extended backplate allows for more cone movement and Finite Element Magnetic optimization ensures that
the magnet flux is used to maximum by controlling the shape of the steel.
J. Strontium ferrite magnet
The powerful Strontium ferrite magnet has been manufactured with high precision which results in narrow frequency
response tolerances and low batch variation.
K. Low compression basket
The design of the basket is an attractive curved shape which has allowed our designers to open up the basket much more
than normally seen on a steel frame without loosing the strength. The low compression design also incorporates venting
below the spider to further enhance the openness of the sound.
12/15/2007 3:40 PM
SLS 10″ Subwoofer Peerless Application Notes
1 of 2
http://www.tymphany.com/datasheet/appview.php?id=37
SLS
10″ Subwoofer
Type Number: 830668
Application notes:
Driver Highlights: Coated paper cone, 39 mm voice coil, AL shorting ring in magnet system.
Go to Data Sheet
12/15/2007 3:39 PM
SLS 10″ Subwoofer Peerless Application Notes
2 of 2
http://www.tymphany.com/datasheet/appview.php?id=37
Tymphany™ and $brandname™ are trademarks of Tymphany Corporation. © 2006, Tymphany Corporation. All rights reserved.
010506
12/15/2007 3:39 PM
Cabinet Design
I was originally seeking a sealed box design based of a recommendation that it would best fit the
design of my chosen Peerless driver. After doing some initial modeling in Winspeakerz, I found the
required volume to house two 10” woofers in a sealed enclosure to be enormous. Although size wasn’t
a huge initial consideration I could recognize that the sealed enclosure wasn’t reasonable for cost,
manageability, and application reasons. As an attempt to salvage the sealed design an isobaric design
was considered at one point. This would halve the modeled 15+ cubic feet down to a slightly more
manageable 7.5 cubic feet. Consequently, the cost of woofers would double an already tight budget.
Once again costs had to be considered and the idea was dropped. It would have been interesting to test
that design in application noting the modeled response is well below 20 Hz with estimated parameters
for the Ensemble Room factored into the Winspeakerz plot. Falling back on the 4th order vented box
design, the modeled response reaches down to about 38 Hz at F(-3dB). The original port configuration
had to be redesigned after construction because of a tuning estimation error. The 4th order vented box
made the best enclosure choice because of its reasonable 3 cubic foot volume and promising bass
response.
128
30
75
126
28
70
124
26
65
122
24
60
120
22
55
118
20
50
116
18
45
114
16
40
112
14
35
110
12
30
108
10
25
8
20
104
6
15
102
4
10
100
2
5
TA
Linear Exc Limit
106
98
SPL 20
50
100Hz
200
500
0 mm
2k Exc
1k
Driver Parameters
Box Parameters
Driver:
System Type: 4th Order Vented Box
D = 10
Nominal Diameter
P= 0
Nominal Power
SPL = 88.7
Sensitivity (1W/1m)
f(s) = 33.3
Free Air Resonance
Q(ts) = 0.51
Total Q
Electrical Q
Q(es) = 0.57
Mechanical Q
Q(ms) = 4.85
Equivalent Volume
V(as) = 2.45
Nominal Impedance
Z= 0
R(e) = 5.6
DC Resistance
Max Thermal Power
P(t) = 0
Max Linear Excursion X(max) = 8
X(lim) = 0
Max Excursion
Voice Coil Diam.
D(vc) = 0
in
Watts
dB SPL
Hz
cu ft
Ohms
Ohms
Watts
mm
mm
mm
Driver Notes:
Peerless SLS 830668 10" Woofer
System Notes:
With a correctly turned port, the system gains SPL output,
a slight bass boost, and exursion falls within the linear
limit.
V(B) =
Box Volume
Closed Box Q
Q(tc) =
Box Frequency
F(B) =
Min Rec Vent Area S(vMin) =
Vent Surface Area
S(v) =
Vent Length
L(v) =
Compliance Ratio
alpha =
Box Loss Q
Q(B) =
3.056
0.8229
35
23.3
9.425
4.283
1.604
7
0 Ohm
Imp
cu ft
Hz
sq in
sq in
in
System Parameters
No. of Drivers
Isobaric Factor
Input Power
SPL Distance
N=
I=
P(in) =
D=
2
1
450
1
(1=normal, 2=iso)
Watts
m
Michigan Tech
1400 Townsend Drive
B24, EERC
Houghton, MI 49931
906.281.1083
System Name:
4th Order Vented Box
Designer:
Title:
Rev Date:
Kyle Persohn
Student
Rev:
Crossover Design
Crossover design options were quite limited due to the response of the chosen drivers. I needed
a crossover point that split the middle between the breakup modes of the Peerless woofer and the
Morel tweeter. 2 KHz turns out to be a common place to do just this. This value is also very friendly for
cost because the physical size and material cost of making components to achieve this are relatively
inexpensive. While 2 KHz is often not recommended for its interference with response in the vocal range
the 4th order nature of my chosen Linkwitz-Design has a very narrowband because of the steep roll-off
and sums to 0dB at 2 KHz. Included in this section are nominal values generated from a crossover
calculator. With a set budget, I tried to purchase the best quality components that money would allow.
Specifically, I made sure to use high quality parts for the series components C1, C2, L3, and L4. For the
parallel components I allowed some sacrifices in quality to keep a strict budget. Parallel combinations of
capacitors are occasionally used to get closer to calculated values than nominal sales values allowed.
Source: LaLena DIY Audio Crossover Calculator
Capacitor
Nominal Value (uF)
Brand(s)
C1
C2
C3
Desired
Value (uF)
5.28
10.55
31.66
4.70 + 0.47 = 5.17
10.00 + 0.47 = 10.47
30.00 + 1.50 = 31.50
C4
7.04
6.80 + 0.22 = 7.02
ClarityCap SA
ClarityCap SA
ClarityCap SA +
Chateauroux Solen
ClarityCap SA +
Chateauroux Solen
Inductor
L1
L2
L3
L4
Desired
Value (mH)
0.40
1.80
0.60
0.30
Nominal
Value (mH)
0.39
1.80
0.62
0.33
Brand
Perfect Winding
Perfect Winding
Sidewinder
Sidewinder
Budget and Accounting
Projected Budget
Drivers
$100
17%
Crossover
Cabinet
Buffer
$50
8%
$300
50%
$150
25%
Actual Allocations
Drivers
$103.15
17%
Crossover
Cabinet
Buffer
$30.56
5%
$305.37
51%
$160.92
27%
Note: This budget does not include materials provided already covered by the course fee in addition to materials already carried
carr in
surplus by the department. An estimated additional $100 was spent on dampening material, wiring, fasteners, floor spikes, finish,
etc not accounted for in the buffer amount..
Invoice 284558
Customer
PLUMM3
EIN# 39-1954726
Ship To:
Bill To:
Christopher Plummer
Michigan Tech Visual & Perf
1400 Townsend Dr, 209 Walker
Houghton, MI 49931
Date
Ship Via
10/15/07
UPS PREPAID
Purchase Order Number
Order Date
Verbal
10/15/07
Quantity
Item Number
Required
Ship
B.O.
Christopher Plummer
Michigan Tech Visual & Perf
1400 Townsend Dr, 209 Walker
Houghton, MI 49931
F.O.B.
Origin
Terms
Visa
Salesperson
AJ
Our Order Number
283930
Tax
Description
Unit Price
Amount
4
4
830668
Peerless SLS 10" Paper cone woofer
N
47.63
190.52
2
2
MDT37
Morel MDT37 Horn tweeter
N
47.37
94.74
1
1
SHIP
Shipping Charge
N
20.11
20.11
NonTaxable Subtotal
Taxable Subtotal
Tax
Total US Dollars
Customer Original (Reprinted)
305.37
0.00
0.00
305.37
Page 1
Invoice 284880
Customer
PLUMM3
EIN# 39-1954726
Ship To:
Bill To:
Christopher Plummer
Michigan Tech Visual & Perf
1400 Townsend Dr, 209 Walker
Houghton, MI 49931
Date
Ship Via
10/23/07
UPS PREPAID
Purchase Order Number
Order Date
Verbal
10/22/07
Quantity
Item Number
Required
Ship
B.O.
Christopher Plummer
Michigan Tech Visual & Perf
1400 Townsend Dr, 209 Walker
Houghton, MI 49931
F.O.B.
Origin
Terms
Visa
Salesperson
AJ
Description
Our Order Number
284235
Tax
Unit Price
Amount
2
2
SA4.7
ClarityCap "SA" 4.7 mfd 630V
N
5.38
10.76
4
4
SA.47
ClarityCap "SA" 0.47 mfd 630V
N
2.85
11.40
2
2
SA10
ClarityCap "SA" 10.0 mfd 630V
N
9.40
18.80
2
2
SA1.5
ClarityCap "SA" 1.5 mfd 630V
N
3.40
6.80
2
2
SA.22
ClarityCap "SA" 0.22 mfd 630V
N
2.49
4.98
2
2
CP30
30.0mfd Polypropylene Capacitor
N
8.13
16.26
2
2
CP6.8
6.8mfd Polypropylene Cap 400V
N
2.81
5.62
2
2
SW.39
Sidewinder .39mh #16 AWG
N
4.63
9.26
2
2
SW1.8
Sidewinder 1.8 mH
N
10.63
21.26
2
2
PL.62
Solen .62MH Air Core #14 Awg
N
13.12
26.24
2
2
PL.33
Solen .33MH Air Core #14 Awg
N
9.44
18.88
8
8
OX6PAN3/4
6 Pan Head 3/4" Black Ox & Wax
N
0.04
0.32
36
36
OX8PAN1
#8 Pan Head 1" Black Ox & Wax
N
0.06
2.16
1
1
SHIP
Shipping Charge
N
8.18
8.18
NonTaxable Subtotal
Taxable Subtotal
Tax
Total US Dollars
Customer Original (Reprinted)
160.92
0.00
0.00
160.92
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MCGANN BUILDING SUPPLY INC.
612 HANCOCK STREET
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*91,17
APFFIOUED
PHONE: (906) 4824340
Rafas.oca
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Drafting Table of Contents
Drawing Title
Concept Design
Page
1
Quantity
-
Material
-
Three View Plan
2
-
-
Dimension Plan
3
-
-
Internal View
4
-
-
3D Skeleton
5
-
-
Outside Front/Back
6
4
MDF
Inside Front/Back
7
4
A/C Ply
Top/Bottom
8
4
MDF
Sides (2 Mirrored)
9
4
MDF
False Bottom
10
2
MDF
Bracing Sub-Assembly
11
2
A/C Ply
Port Sub-Assembly
12
2
ABS Plastic
Side Section View
13
-
-
Top Section View
14
-
-
Exploded View
15
-
-
2
1
B
B
A
A
TITLE
PROJECT
Concept Design
DRAFTED AND
DESIGNED BY
2
Kyle Persohn
SHEET
DATE
Loudspeaker Design
1 OF 15
10/21/2007
1
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REVISION
1:8
1.0
2
1
B
B
A
A
TITLE
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Three View Plan
DRAFTED AND
DESIGNED BY
2
Kyle Persohn
SHEET
DATE
Loudspeaker Design
2 OF 15
10/21/2007
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1.1
2
1
.75
11.50
B
B
6.25
14.28
22.31
n3.69
n2.84
n10.34
n8.81
61.00
62.50
11.50
n2.88
n2.41
A
A
17.00
.75
13.00
12.50
TITLE
PROJECT
Dimension Plan
DRAFTED AND
DESIGNED BY
2
Kyle Persohn
SHEET
DATE
Loudspeaker Design
3 OF 15
10/21/2007
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1.5
2
1
B
B
A
A
TITLE
PROJECT
Internal View
DRAFTED AND
DESIGNED BY
2
Kyle Persohn
SHEET
DATE
Loudspeaker Design
4 OF 15
10/21/2007
1
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1.1
2
1
B
B
A
A
TITLE
PROJECT
3D Skeleton
DRAFTED AND
DESIGNED BY
2
Kyle Persohn
SHEET
DATE
Loudspeaker Design
5 OF 15
10/21/2007
1
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1:7
1.1
2
1
12.50
.75
B
B
62.50
A
A
TITLE
PROJECT
Outside Front/Back
DRAFTED AND
DESIGNED BY
2
Kyle Persohn
SHEET
DATE
Loudspeaker Design
6 OF 15
10/21/2007
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1
.75
11.00
B
B
61.00
A
A
TITLE
PROJECT
Inside Front/Back
DRAFTED AND
DESIGNED BY
2
Kyle Persohn
SHEET
DATE
Loudspeaker Design
7 OF 15
10/21/2007
1
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1.1
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1
11.50
.75
B
B
12.50
A
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TITLE
PROJECT
Top/Bottom
DRAFTED AND
DESIGNED BY
2
Kyle Persohn
SHEET
DATE
Loudspeaker Design
8 OF 15
10/21/2007
1
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REVISION
1:4
1.1
2
.75
1
5.75
B
B
48.00
61.00
.75
.25
A
A
11.50
.75
TITLE
PROJECT
Sides
DRAFTED AND
DESIGNED BY
2
Kyle Persohn
SHEET
DATE
Loudspeaker Design
9 OF 15
10/21/2007
1
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1.3
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1
.75
10.00
B
B
11.50
A
A
TITLE
PROJECT
False Bottom
DRAFTED AND
DESIGNED BY
2
Kyle Persohn
SHEET
DATE
Loudspeaker Design
10 OF 15
10/31/2007
1
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1.1
2
1
1.50
11.00
.75
B
B
9.53
8.50
.75
6.00
39.00
4.00
A
A
9.00
4.00
1.00
TITLE
PROJECT
Bracing Sub-Assembly
DRAFTED AND
DESIGNED BY
2
Kyle Persohn
SHEET
DATE
Loudspeaker Design
11 OF 15
10/31/2007
1
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1:6
1.2
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1
n2.47
B
B
13.75
A
A
7.75
TITLE
PROJECT
Port Sub-Assembly
DRAFTED AND
DESIGNED BY
2
Kyle Persohn
SHEET
DATE
Loudspeaker Design
12 OF 15
11/4/2007
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C
.16
1.00
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B
12.25
A
SECTION C-C
C
TITLE
PROJECT
Side Section View
DRAFTED AND
DESIGNED BY
2
A
Kyle Persohn
SHEET
DATE
Loudspeaker Design
13 OF 15
10/21/2007
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B
B
G
G
A
A
TITLE
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Top Section View
DRAFTED AND
DESIGNED BY
2
Kyle Persohn
SHEET
DATE
Loudspeaker Design
14 OF 15
10/21/2007
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1.2
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B
B
A
A
TITLE
PROJECT
Exploded View
DRAFTED AND
DESIGNED BY
2
Kyle Persohn
SHEET
DATE
Loudspeaker Design
15 OF 15
10/21/2007
1
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1:8
2.1
Construction Notes
11-01-2007
I’m a little worried about the initial cuts because all of the initial MDF cuts weren’t supposed to fit on
two sheets of stock MDF. Somehow they all did. I’ve double and tripled checked the measurements
against my AutoCAD cut sheets and the Inventor solid models but all appears to be correct. Something
doesn’t add up. Also, I’m extremely disappointed with the A/C plywood. It was not worth the cost at all.
I would prefer a standard sheet of B/B over the stock I got any day. It is extremely warped and quite
ridged so it splinters easy when cutting.
11-03-2007
I cleaned up all of the panel saw rips with the table saw. All of the main cabinets pieces are cut down to
size so I have two complete shells at least. I also made the discovery that MDF comes in 49” stock
sheets. This accounts for the mismatch on my cut sheet. The two side panels don’t spill over onto a
new sheet anymore so one whole less sheet of MDF has been eliminated. After much fun trying to
setup jigs for the router I have started cutting the T-slots in for the false bottom and the cross-bracing
joint on the side panels.
11-06-2007
Utilizing a dry assembly with clamps I predrilled the two baffles together to create precision alignment in
preparation for the gluing stage. Application of glop between the inner and outer baffles went quite
well. The A/C ply is warping a lot, so much that the MDF is bending with it. At least it centered nice
because of my pre-assembly. I also cut the majority of the cross-bracing pieces. I may want to adjust the
thickness of the vertical runners to provide a larger gluing surface for the cross pieces to stick to.
11-08-2007
Today, I learned that PVC does not come in a nominal 2.5” ID size contrary to what the Autodesk
Inventor Standard Parts Library thought. I’ve settled on stepping down to 2” because the 3” modeling
doesn’t look like it is going to work very well. I have new numbers from Winspeakers and will need to
update the drafting accordingly. I still think this port seems extremely long and suspect something may
be wrong with it. I will also be using ABS plastic instead of PVC because it is black and won’t require
painting to blend in with my intended truck-bed finish coat.
11-11-2007
I finished all of the T-slotting with the new Makita router. The guide is really great for one-pass routes
but isn’t too handy for slots wider than the width of the router bit. If I had a ¾” end-mill bit the one pass
fence technique would work wonders. However since the ½” bit is being used to make a wider slot I
probably would have been better off with the custom fence approach as used before.
Because the stamped frame of my woofers is so thin, I have made the decision not to recess them. As
the gasket tape gets compressed to the MDF there is virtually no thickness offset. I will still continue to
recess the tweeter which has a much thicker edge and naturally the high frequencies are more sensitive
to diffraction.
Using a “poor man’s caliper” comprised of scrap wood, a square, and a tape measure I’ve successfully
estimated the diameter of the drivers and found them to be slightly larger than listed in their PDF’s. The
holes sizes will be rounded up to the next nominal size on the circle jig to allow some wiggle room.
The router bit isn’t deep enough to make it through both layers of baffle so the driver holes will have to
be approached from both sides. While I didn’t want to do this for accuracy sake, it really won’t matter in
the end because the mismatch will be on the interior and therefore not visible.
11-13-2007
Finished routing the driver holes. Glue. Glue. Glue. Got two coffins now. Assembly with the drywall
screws was a horrible choice because the thread is too fine for MDF.
11-14-2007
Wiring and mounting everything took way longer than expected. The crossover is setup externally and
the drivers are wired to the NL-4 Speakon jack so the crossover can be tuned without removing the
back. Speaking of the back, the warped nature made it difficult to put on. I’m not looking forward to
having to remove it for any reason.
Perhaps the most important lesson of the night was on how to properly wire inductors. After much
aggravated troubleshooting I found out that the ends of two my inductors didn’t come pre-filed so they
weren’t passing current. After re-crimping the terminal ends to the conductive inductor the low
frequencies we’re much more prominent.
Warped back was interesting
11-15-2007 02:00am
They make sound!
HF + LF
Drafting Table of Contents
Drawing Title
Concept Design
Page
1
Quantity
-
Material
-
Three View Plan
2
-
-
Dimension Plan
3
-
-
Internal View
4
-
-
3D Skeleton
5
-
-
Outside Front/Back
6
4
MDF
Inside Front/Back
7
4
A/C Ply
Top/Bottom
8
4
MDF
Sides (2 Mirrored)
9
4
MDF
False Bottom
10
2
MDF
Bracing Sub-Assembly
11
2
A/C Ply
Port Sub-Assembly
12
2
ABS Plastic
Side Section View
13
-
-
Top Section View
14
-
-
Exploded View
15
-
-
2
1
B
B
A
A
TITLE
PROJECT
Concept Design
DRAFTED AND
DESIGNED BY
2
Kyle Persohn
SHEET
DATE
Loudspeaker Design
1 OF 15
12/15/2007
1
SCALE
REVISION
1:8
1.1
2
1
B
B
A
A
TITLE
PROJECT
Three View Plan
DRAFTED AND
DESIGNED BY
2
Kyle Persohn
SHEET
DATE
Loudspeaker Design
2 OF 15
12/15/2007
1
SCALE
REVISION
1 : 10
1.2
2
1
.75
11.50
B
B
6.25
14.28
22.31
n3.69
n2.84
n8.81
61.00
62.50
11.50
n2.38
A
A
17.00
.75
13.00
12.50
TITLE
PROJECT
Dimension Plan
DRAFTED AND
DESIGNED BY
2
Kyle Persohn
SHEET
DATE
Loudspeaker Design
3 OF 15
12/15/2007
1
SCALE
REVISION
1 : 10
1.6
2
1
B
B
A
A
TITLE
PROJECT
Internal View
DRAFTED AND
DESIGNED BY
2
Kyle Persohn
SHEET
DATE
Loudspeaker Design
4 OF 15
12/15/2007
1
SCALE
REVISION
1 : 10
1.2
2
1
B
B
A
A
TITLE
PROJECT
3D Skeleton
DRAFTED AND
DESIGNED BY
2
Kyle Persohn
SHEET
DATE
Loudspeaker Design
5 OF 15
12/15/2007
1
SCALE
REVISION
1:7
1.2
2
1
12.50
.75
B
B
62.50
A
A
TITLE
PROJECT
Outside Front/Back
DRAFTED AND
DESIGNED BY
2
Kyle Persohn
SHEET
DATE
Loudspeaker Design
6 OF 15
12/15/2007
1
SCALE
REVISION
1:8
1.2
2
1
.75
11.00
B
B
61.00
A
A
TITLE
PROJECT
Inside Front/Back
DRAFTED AND
DESIGNED BY
2
Kyle Persohn
SHEET
DATE
Loudspeaker Design
7 OF 15
12/15/2007
1
SCALE
REVISION
1:8
1.2
2
1
11.50
.75
B
B
12.50
A
A
TITLE
PROJECT
Top/Bottom
DRAFTED AND
DESIGNED BY
2
Kyle Persohn
SHEET
DATE
Loudspeaker Design
8 OF 15
12/15/2007
1
SCALE
REVISION
1:4
1.2
2
.75
1
5.75
B
B
48.00
61.00
.75
.25
A
A
11.50
.75
TITLE
PROJECT
Sides
DRAFTED AND
DESIGNED BY
2
Kyle Persohn
SHEET
DATE
Loudspeaker Design
9 OF 15
12/15/2007
1
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REVISION
1:8
1.4
2
1
.75
10.00
B
B
11.50
A
A
TITLE
PROJECT
False Bottom
DRAFTED AND
DESIGNED BY
2
Kyle Persohn
SHEET
DATE
Loudspeaker Design
10 OF 15
12/15/2007
1
SCALE
REVISION
1:4
1.2
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1
1.50
11.00
.75
B
B
9.53
8.50
.75
6.00
39.00
4.00
A
A
9.00
4.00
1.00
TITLE
PROJECT
Bracing Sub-Assembly
DRAFTED AND
DESIGNED BY
2
Kyle Persohn
SHEET
DATE
Loudspeaker Design
11 OF 15
12/15/2007
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B
B
n2.38
n2.07
2.00
A
A
TITLE
PROJECT
Port Sub-Assembly
DRAFTED AND
DESIGNED BY
2
Kyle Persohn
SHEET
DATE
Loudspeaker Design
12 OF 15
12/15/2007
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J
.16
1.00
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B
12.25
A
SECTION J-J
J
TITLE
PROJECT
Side Section View
DRAFTED AND
DESIGNED BY
2
A
Kyle Persohn
SHEET
DATE
Loudspeaker Design
13 OF 15
12/15/2007
1
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REVISION
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SECTION K-K
B
B
K
K
A
A
TITLE
PROJECT
Top Section View
DRAFTED AND
DESIGNED BY
2
Kyle Persohn
SHEET
DATE
Loudspeaker Design
14 OF 15
12/15/2007
1
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REVISION
1 : 10
1.3
2
1
B
B
A
A
TITLE
PROJECT
Exploded View
DRAFTED AND
DESIGNED BY
2
Kyle Persohn
SHEET
DATE
Loudspeaker Design
15 OF 15
12/15/2007
1
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REVISION
1:8
2.2
Initial Listening Evaluation
My very first initial listening evaluation took place at 2am in the morning as described in my
testing journal. Because I was so exhausted I did not notice the left channel’s woofers weren’t hooked
up. I decided to discard this evaluation in favor of discussing the one that was done as an entire class
with consistent tracks for comparison. I like the low end extension thus far compared to other two-way
systems but I’m hoping to still get more out of it. John’s 3-way system has been motivation for trying to
get the most out of this system. Being able to hear his system next to mine has given me good
benchmarks for not accepting my bass response as is and striving to achieve as close to a 3-way’s sound
as I can. The stereo image is well contained within the cabinets but isn’t so narrow it sounds mono. This
should work out well for a “sitting at desk” application. The upper mid to highs are a bit harsh at this
point. While testing I hope to see what dampening can do for this and if that doesn’t solve the problem
investigate impedance correction or a pad on the tweeter.
The class’s reviews of my speakers have some mixed results but given we all haven’t had much
experiencing loudspeakers I suppose that is to be expected. For example, as a class we can’t seem to
agree whether the mid frequencies are too present or not present enough. Either way, the important
part is most agree there isn’t uniformity in this region and I will make a point to address it in testing.
Most of my classmates are impressed with the bass response as-is, but a few recognize that there is still
room for improvement. Comments about the stereo image and depth are inconsistent. Some feel that
the image is narrow for the physical size of the speakers, others feel that the size fits the spacing nicely,
and still yet there are also those that believe the image graciously fills the room. Most importantly, no
one justified there response in this category as something that detracts from any of my design goals.
We all agree that 212 has some limitations as a test environment so will pay more attention to these
comments when the speakers are in there actual home. Included in this section are the actual responses
that this summary is based off of.
Testing and Tuning Notes
11-15-2007 – Initial Listening
It’s 2am and I’m just so thrilled they are making noise ahead of the due date anything sounds glorious
coming from these cabinets. I think the system is a little bit right biased at this point and the tweeter is a
little hot but other than that I’m quite happy with them for a first run. The punchyness is welcome and
they are very capable of loud volumes.
11-16-2007
Now that my brain is functioning again all of the drivers are hooked up for the second run. Having the
left woofers unplugged last night explains the bias and tweeters being overpowering. The bass has
greatly improved but the upper-mids are a little harsh still.
11-29-2007 - First In-Class Listening
I like how these speakers handle loud volumes compared to some of the other systems. I’m not getting
the frequency extension that John has but the notes are a lot crisper however. Hopefully dampening will
solves some of the upper-mid issues.
11-30-2007 – Initial Testing before ANY modifications [212, <1M, 4010]
Key Format: T[Test Number]-[Left|Right]-[Tweeter|Woofer|Full Range]-[Modifications]
Ex. T1-R-FR-T^-1 = Test 1, Right Speaker, Full Range, Tweeter Inverted
Looks like I need to re-tune the port. Back to Winspeakers for reworking the length.
I might have some cancellation issues at the crossover point.
Looks like phase inverting one of the drivers will solve the cancellation issue. There is still some uppermid boost that will need to be addressed with dampening and impedance correction.
Between tests I added BlackHole, completely re-tuned the port, and coated them in truck bed liner.
12-07-2007 – Testing with Modifications [McArdle, 2M, M30]
Impedance graph is looking much better with the correctly tuned port. There is still a little bit of oddity
but I want to listen to the system before making any drastic changes. If anything the port could be
slightly shorter to even out the two humps surrounding the tuning frequency.
Phase inverting the woofer makes all the difference between summing and cancellation at the crossover
point. There is still an ugly boost slightly above 1K however. Looks like dampening didn’t completely
resolve the issue as I had expected.
I added a capacitor and a resistor hooked in series across the positive and negative terminals of the
woofers to add impedance correction. Values were calculated based off the formula in the Loudspeaker
Cookbook. As shown above, the correction circuit nicely reduces the impact of the rising woofer
impedance with frequency.
The correction circuit did an effective job of eliminating the undesired bump above 1K. The frequency
response is now pretty stable (within 3dB) overall. Accurate resolution on this test equipment is from
about 100 Hz up to 10 KHz. Regions outside this range should be ignored.
The left speaker had some similar issues to start out as well.
All of the corrections were applied and it now looks almost like the right speaker. There is just a slight
dip around the crossover that doesn’t seem to be summing quite as well as the right speaker did.
As an interesting side note, here is a comparison between an EarthWorks M30 linear test microphone
and a Behringer ECM8000 with all other variables kept identical.
M30 M.S.R.P - $795.00
ECM8000 M.S.R.P - $64.99
After listening to the system again in 212 I have decided that the harshness has subsided with the
changes I made in McArdle. The newly tuned port produces acceptable bass so I will not mess with the
tuning any further. The addition of floor spikes also improved the transient response.
fourier.jpg (JPEG Image, 500x361 pixels)
1 of 1
http://imgs.xkcd.com/comics/fourier.jpg
12/17/2007 2:56 PM
Final Listening Evaluation
The final listening evaluation took place in 210. Given a number of circumstances I didn’t think
my speakers performed as well in this space as they did in others. First, they are specifically designed
for a close together, up front, and seated listening place. The off-centered distant evaluation I did in 210
made seemed very spacious and open. Without being such a confined space they suffered from the lack
of room gain and didn’t feel quite as bassy as before. I think there were significant improvements from
before in spectral uniformity but oddity of the layout made those improvements hard to distinguish. I
am confident my speakers are performing better than before from tests in other locations which I will
discuss further in my Final Repot. I was, however, displeased with the performance in 210.
Flaws in the standardized testing environmental layout and logistical procedures led to very
mixed responses from the audience. For one thing, I made it clear in my design statement that these
were designed for rocking out at high SPL levels, but I never got to actually demonstrate this in testing.
While it was important to have a few tracks that each set played for comparison sake there was much
need for some builder selected tracks that could exemplify the unique characteristics of the constructed
loudspeaker. While everyone didn’t particularly love the way they turned out, the general consensus
seemed to be that they were “well fitting of the design goals” and “suiting their purpose well.” Because
the comments on stereo image and depth were so varied from reviewers scattered about the room it
was hard to determine what comments if any were very legitimate. It is also interesting to note that
mine were the first setup and they performed much differently without any of the others present in the
room. Once the “wall of sound” was created ,my system seemed to get muddier than it was all by itself.
Again, the raw data collected from my peers is included in this section for reference.
Final Report
All things considered I’m very happy with the final product I have produced as an outcome of
this project. I set out to make a high fidelity speaker capable of reaching pro-sound levels similar to a PA
system. While the constructed system wouldn’t necessarily be good for sound reinforcement in a
concert hall space, the speakers perform well in their new home, the Hagen Practice Room in the Rozsa
Center. From a measurement standpoint, the numbers and graphs speak well for this system. Also, and
perhaps more importantly, they perform well acoustically and my peers even agree that they fit their
intended purpose.
After testing and tuning I was extremely pleased with this system’s performance in Walker 212. I
listened extensively to many different tracks including ones from the Transducer Theory Test CD, the
MTU Studio Test CD, and my own personal selections which better represented material most likely to
be used on this system in the future. I was particularly pleased with the low end clarity of the upright
bass and also how I Know My Love didn’t sound congested and overwhelming like it did on other
systems. I wasn’t as impressed with the sound in Walker 210 as previously discussed in my Final
Listening Evaluation. More importantly the speakers fit in quite well in Rozsa 209 where they were
intended to live. Most of my objections to the way they sound in that room are from other elements in
the signal chain. The class D Sampson amplifier doesn’t quite match up to the Rotel that had been used
for prior listening. Additionally, the M-Audio FireWire 410 most likely has the same high frequency shelf
as the one in Walker 212 which would explain some upper harshness. I conclude that based on what I
know they are capable of from tests in 212 some changes to the signal chain and perhaps a little bit of
physical rearrangement could improve their performance in 209.
From a measurement standpoint, my system has impressive plots as well as plots that leave
some uncertainty. The measurements taken in McArdle theatre where reflections could easily be
isolated show an impressively flat response as shown in Figure 1.
Figure 1: Right Cabinet, McArdle Theatre
In Rozsa 209, the reflections off the walls clutter the frequency response to the point where it looks
much uglier. Measurements were taken on the listening plane where a user would sit at the computer
workstation. When eliminating the reflections, the low frequency resolution only extends down to 2
KHz making the measurement completely useless. Shown in Figure 2 is an average of both channels in
209 with no reflections isolated.
Figure 2: Average of LR, Rozsa 209
A sense of agreement that I met my design goals well is the most valuable information I got
from my peers during evaluations. Without giving reviewers any prior instruction and few of them
having much relevant experience to speaker reviewing conflicting and confusing reports are to be
expected. From comments beyond the review sheets themselves I got a good sense that this system
exceeds the expectations of a typical 2-way system in terms of frequency while being capable of
ridiculously high sound pressure level outputs. Given this feedback in conjunction with my budget
staying in control, I feel I met my design requirements quit well. The final product balances lowfrequency extension, loudness capability, and cost in a highly effective package.
As with any project there were many valuable learning experiences gained from “do it yourself”
nature of this construction process. In future designs, I would be certain to hand pick my stock wood
sheets to avoid the bad experience I had with the A/C plywood. I also know how to correctly tune a
vented enclosure so my port could be more proportional and less noisy in the future. While the
aesthetics of this system fit their purpose well, I look forward to producing an eye pleasing professional
looking system that borrows the black baffle on stained enclosure idea. Although it doesn’t show up on
the outside, caulking would have been much easier and neater had I done it before securing the bracing
internally. Lastly, given more flexibility in dimensions the next system I design will have pieces that are
more easily manageable on the given construction equipment. Smaller or at least portioned panels were
much easier to produce accurately which would seem to directly impact the visual and acoustic turnout
of the final product.
I am also proud of many cunning ideas whether intentional or not that worked out to make my
building process more sucessful. Planning cut sheets to keep similar sized edges on the same pass
through the saw or at least during the same fence set made all the difference when matching up joints
for assembly. Additionally, the T-slotted fittings made for a rock solid cross-bracing and appeared to be
less of a headache than the “box in a box” design that was employed by many of my peers. A 4-pole
connector is a must for testing and tuning. Even with an easily removable back having the option to
initially run the crossover externally without hassle made adjustments much simpler.
In the end, I’m proud to present a unique set of speakers to the Michigan Tech Visual and
Performing Arts Department. I’m a bit disappointed I can’t take them home, but they will perform well
in their new home. Along the way I’ve learned some valuable lessons about what worked and what
didn’t so I can make improvements when it comes time to build a set my own.