Which CD Recorder Issue 16

Which CD Recorder?
Stand-alone CD recorders have become increasing affordable. But what makes one better than
another, and what features do you need? Howard Jones explains.
I
n this issue we are taking a look at the increasingly popular, and
increasingly affordable, stand-alone CD Recorder segment of the
marketplace. Apart from the simple question of cost, there are
other issues at work when considering which machine to buy – and
I’ve been entrusted with the task of outlining some of these issues.
First of all, let’s examine a few of the general questions that you
might want to think about before we move on to the specifics about
CD-Rs and CD-RWs.
Take a look at the equipment which you are already running and
decide whether you need to put an accent on pro features like rack
mounting, balanced analogue I/O, extensive digital interfacing etc.
Perhaps you’ll be doing a lot of text editing, so do you want the
ability to connect a keyboard? Will you be using the machine for
preparing CD masters for replication or more for building up compositions and arrangements at home? Will you need to be copying
tracks from a PC? The answers to these questions will begin to
steer you in one direction or another.
How They Work
CD recorders use blank discs that contain an organic photosensitive
dye layer. The green discs use cyanine, a compound that is quite
sensitive to sunlight and has a rated life of around 10 years.
Meanwhile, the gold discs use phthalocyanine, which reportedly has
a 100-year life span. You’ll also notice other dye types in use, but
these are the main ones. The recorder uses a laser to introduce
chemical changes in the dye layer such that when the disc is played
back in a CD player light is reflected or scattered in the same way
as any other commercially produced CD in your collection. Once
the disc is recorded in this way, it can’t be erased and re-recorded.
However, CD burners will also generally record CD-RW blanks
which are re-recordable, so make sure that your intended purchase
has this capability. Being able to re-record is ideal for musos who
are working up arrangements and ideas that they can see themselves wanting to alter. A completed CD-RW will play back in a CD
recorder and some DVD players but, due to the quite low reflectivity of the discs, will only play in CD players specifically rated for
CD-RW playback. A CD-RW is not, therefore, the right choice for
mastering purposes.
Obviously, being a stand-alone device with audio inputs, a CD
burner records in real time. CD burners attached to a SCSI or
UDMA bus behave more like a data recorder and the discs they use
are data discs rated for recording at 2x, 4x or even higher. Some
manufacturers of stand-alone devices advise you to use discs
specifically rated for recording at 1x, so you should think about the
potential costs involved here.
Choice of CD Blanks
Overall, you will probably end up finding that your choice of CD
blanks affects the performance of the end product (the reasons for
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this are outside the scope of this present article). Suffice it to say
that you should expect to do a little experimenting when you first
purchase a recorder to see which brand and type of blank best suits
your machine. It’s helpful if you can hook up with a CD replication
house or high-end facility that has a CD analyser and send them
some test recordings off your machine. They will be able to produce
a printed report showing the error rates and other performance
parameters for your discs. This way, you’ll know that your CD-Rs are
of an acceptable quality for CD replication. If getting access to this
sort of analysis is beyond your reach, you could do worse than to
use the blanks recommended by the recorder’s manufacturer.
When assembling a CD you can record the disc track by track or
all at once. If you choose the former method, the laser is turned off
at the end of each track. This tends to lead to high block error rates
(BLER) at these points, and can present difficulties if you intend to
use the disc for CD mastering purposes. (Track At Once recording
is good for assembling bits and pieces, but Disc At Once is the
method of choice if your disc is to be sent for replication.) So if
you’re keen to minimise errors in the recording you’ll generally
need to compile and editing your material in a PC or workstation
until it is assembled in the desired order and then digitally transfer it
to the burner. The laser will then run all the way through the tracks
and on to the finalising stage without switching off.
By the way, most blanks that you will see on sale can record up
to 74 minutes of audio – the recommended maximum for the
format. Some are shorter, which is said to give even better results,
but some offer 79 to 80 minutes of recording time. In order to do
this, these discs push the envelope of the format to an unsafe level
– so avoid them, as the final product may exhibit nasty problems.
16-bit Format, 24-bit A/D?
Although the CD format is limited to 16-bit recording, most studio
equipment now offers up to 24-bit encoding. Indeed, many of the
burners featured in this overview have 24-bit A/D converters on
their analogue inputs. Clearly, therefore, a 24-bit signal needs to be
modulated to 16-bit to actually be recorded on the blank. CD
recorder manufacturers have similar but slightly different methods
of achieving this – you’ll see terms such as dithering, super bit
mapping (SBM), UV-22 etc. These methods use mathematical
manipulation based on psychoacoustic techniques to achieve their
results. But they all share the same method of initially encoding the
signal with the highest possible resolution while still conforming to
the needs of a 16-bit format. This is definitely a desirable feature
and one you should look for in your intended purchase.
When deciding to buy a burner, don’t forget that it contains
working parts that will eventually wear out. The laser, which records
the blanks, won’t run forever and you’ll need to factor in service or
replacement costs down the track – perhaps your next purchase
will be a DVD-Audio burner.
And, a word on the environment in which you use
your recorder. A burner should be provided with
good ventilation around its case and, hopefully, controlled temperature and humidity. In theory, a burner
should not be unduly affected by (low levels of)
vibration, but it’s best to have your machine on an
anti-vibration mat and/or vibration free surface. In
other words, avoid running your burner in direct
sunlight in front of your speaker stack right beside
the main walkway!
Consumer/Pro/Prosumer
CD-R/RW recorders can be divided into consumer,
low-end professional and high-end professional
models, although, in preparing this article I found that
some of the distinctions between these categories are
beginning to blur. Probably the single most important
caveat about the pure consumer models is that they
will only record on what are known as ‘music only’
blanks. [The other caveat is that you have to deal with
the staff at Harvey Norman – CH.] These blanks
(stamped ‘for consumer use’) have a royalty fee
included as part of the purchase cost and include a
digital signature that the recorder is programmed to
look for. In other words, such a recorder won’t record
on regular blanks. Apart from being more expensive,
the availability of these ‘music only’ blanks has been
somewhat limited. However, be aware that there are a
couple of the low-end pro models that still have this
limitation – check before you buy.
The consumer models have a lot in common with
the low-end pro models in other respects as well.
Both categories of machine will generally record
either CD-Rs or CD-RWs, offer sample rate conversion, OPC, CD text recording, TAO & DAO, synchro
recording and come with a remote control. Both
types will have unbalanced analogue I/O and
S/PDIF digital I/O, but the consumer units will
come with SCMS.
The extra features the high-end pro models bring
to the party are the likes of: rack mounting, balanced
analogue I/O, AES digital I/O, 24-bit A/D and D/A,
the ability to generate copy prohibit on discs that you
burn, and the ability to ignore SCMS at the digital
inputs (check the glossary for more on SCMS). In
addition, you would expect that the jitter specs for the
digital inputs would be very good, and look around
for extra bells and whistles such as the ability to
connect a PS/2 keyboard, a wired remote and DSP
(digital signal processing) options. These might
include digital EQ and limiting which can be used as
the final refinement in your mastering. And it goes
without saying that these pro machines will offer a
system for down converting from 24-bit to 16-bit.
Finally, in any model that you are close to
deciding on, check that the menu structure is clear
and easy to navigate, the buttons easy to operate
and the displays bright and sensible. You don’t want
to be hitting the erase button by mistake!
Glossary
AES/EBU: AES is the standard for digital I/O on professional equipment. There are
several important differences between AES and S/PDIF (the other main digital
protocol). The electrical specs for the two are different, as the idea is that AES might
need to go over long cable lengths while S/PDIF would just be connecting consumer
gear together over short runs (S/PDIF has now become a fixture of the recording
studio but this wasn’t its original purpose). AES normally appears on XLR connectors, while S/PDIF will appear on either an RCA (aka phono) socket or optical
connector .(Trap: some devices use only one type of connector for both protocols –
you will find a setting somewhere in the guts of the software which tells the hardware
the type of signal to transmit.) AES is balanced; S/PDIF is unbalanced. In both
cases, the data to be transmitted is assembled into frames (groups of digital words)
that are sent at a certain frequency – and for both systems the frame sizes and
transmission frequencies are the same. This means that putting AES into an S/PDIF
input (and vice versa) often works okay. However, the internal structure of the frames
is different. AES can carry 24-bit data, S/PDIF is limited to 16 bits. With those extra
unused eight bits, S/PDIF can pack other data such as track IDs into its transmission. Therefore, if you are having trouble transferring IDs from your DAT to your CDR, it may be that you’re using AES – this won’t work. Also, don’t forget that S/PDIF
will carry the copy prohibit flag over, AES won’t.
Burner: A CD recorder is colloquially known as a burner. Creating a CD is called
burning a CD.
Calibration: CD recorders use a special portion of the blank CD to do a test burn,
allowing it to read and optimise the laser power for the given blank.
CD Text: The CD format allows for attaching names to discs and tracks. This text is
written to the disc during the process of finalising and therefore has to be entered
just beforehand.
Clone: An exact replica of existing digital data.
DAO: Disc At Once – the entire CD blank is recorded in one go without the laser
pausing or being turned off. The lead out & TOC is written as part of this process.
Finalising: The process of writing the lead out and TOC to a disc and thus completing it. In the case of Track At Once, the disc does not need to be finalised immediately. Once it is, however, no further tracks can be added to that disc. An unfinalised disc can’t be played on a regular CD player, but it will play back in the
recorder and may do so in some pro players.
Fixing up: The original term for finalising.
Flag: A digital signpost. The tracks on a CD are preceded by music start flags that tell
the player a new track is about to begin. Many players use these flags rather than the
embedded absolute time references in the TOC to locate to a track.
OPC: Optimum Power Control. Used on many burners to optimise the laser record
power to the blank. See calibration.
PMA: Program Memory Area – used only on a CD-RW, much like a TOC it is used
to hold intermediate information when a disc is written in different sessions.
SCMS: Serial Copy Management System – popularly known as ‘scums’. SCMS is
designed to allow you to make a single digital copy of a CD (or DAT) while preventing any further copies from that first copy. It does this by inserting a copy prohibit bit
into the digital data stream, which is sent from the originating device. This tells any
second generation device to lock out the digital signal i.e. you can’t make a clone of
a CD which is carrying the copy prohibit bit.
S/PDIF: Sony/Philips Digital Interface – the standard for digital I/O on consumer
equipment. See AES.
SRC: Sample Rate Conversion. The CD recording sample rate is strictly defined as
44.1k. However, many DAT and video recorders work at 48k and so, if you want to
do a digital transfer, it is necessary to convert from the one sample rate to the other.
Most burners now include this facility as standard.
TAO: Track at Once – the CD blank is recorded track by track. The final CD is thus
built up track by track over time and the TOC has to be recorded separately at the
end of this process.
TOC: Table Of Contents. It is part of the basic spec of the CD format that each disc
has at its start a table that describes the contents of the disc and where to find
the tracks. If a player can’t read the TOC then it won’t play the disc. It is an
important part of the function of a burner to write the TOC when finalising the disc.
Word Clock: A signal used to synchronise digital equipment. Word clock may be
used to bring all the (digital) machines in a studio into synchronous operation so that
there are no glitches in the digital I/O. Not strictly necessary if a burner can sync to
its digital input.
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The Contenders
Manufacturer: Sony
Manufacturer: HHB
Burn-It is HHB’s low cost model, but apart from the lack of
balanced I/O, there’s a good array of pro features. You can input
display text, there’s a an SCMS-free digital input and gain control
on the digital input – which can be handy if you’re piecing together
a CD from various digital sources.
HHB’s CDR850 and 850Plus address the upper end of the
market – there’s a good complement of I/O. The 850Plus distinguishes itself with its word clock input and associated dip switches
which allows you to select the master clock source (either via the
word clock input, AES/EBU input, S/PDIF coax and optical inputs
or the recorder’s internal clock).
Audio Products Australia: 1800 642922
Manufacturer: Yamaha
The Yamaha
CDR1000
features balanced
analogue and
digital I/O and a
word clock input, but
probably its standout
feature is the inclusion of Apogee’s UV22 Super CD 16-bit
encoding (see preceding article for more). It’s a smart looking unit
with the word ‘Professional’ appearing prominently on the CD tray
and with many of the features to warrant it.
Yamaha Australia: 1800 805413 or aust_pasupport@infomta.post.yamaha.co.jp
Sony’s CDR-W33 and CDR-W66 are closely related, with the fundamental difference being the selection of I/O on the rear. Both
units pack some interesting features. Sony’s Super Bit Mapping (see
more on SBM in Howard’s preceding article) dither system is
included, CD Text data can be input via a PC keyboard or from the
front panel, and digital limiting and three-band equalisation comes
as an added bonus.
Sony Australia: 1800 017669
Manufacturer: Tascam
Tascam have their CR-RW700 and CR-RW2000 in their range. Both
units share similar features, with the CR-RW2000 playing the part of
big brother, sporting balanced I/O and word clock input. Both have
24-bit A/D and D/A converters, digital gain adjustment, and digital
processing of fade in and fade out from 3 to 30 seconds. There’s also
a monitor function that allows these units to be used as an A/D
converter or
sample rate
converter, without
the need to place a
recordable disk in
the tray or enter
record mode. The
700 will rack
mount (as will the
Model
Analogue I/O Digital Input
Digital Output
Converters
Sample
Rate
Conversion
HHB Burn-it
phono
S/PDIF coax & optical
S/PDIF coax & optical
24-bit
yes
HHB CDR850
XLR & phono
S/PDIF (coax & optical) & AES/EBU
S/PDIF coax & optical
24-bit
yes
HHB CDR850 Plus
XLR & phono
S/PDIF (coax & optical) & AES/EBU
S/PDIF (coax & optical) & AES/EBU
24-bit
yes
Yamaha CDR1000
XLR
S/PDIF (coax) & AES/EBU
S/PDIF (coax) & AES/EBU
24-bit
yes
Sony CDR-W66
XLR & phono
S/PDIF (coax & optical) & AES/EBU
S/PDIF (coax & optical) & AES/EBU
24-bit
yes
Sony CDR-W33
phono
S/PDIF (coax & optical)
S/PDIF (coax & optical)
24-bit
yes
Tascam CD-RW2000
XLR & Phono
S/PDIF (coax & optical) & AES/EBU
S/PDIF (coax & optical) & AES/EBU
24-bit
yes
Tascam CD-RW700
Phono
S/PDIF (coax & optical)
S/PDIF (coax & optical)
24-bit
yes
Fostex CR300
XLR & Phono
S/PDIF (coax & optical) & AES/EBU
S/PDIF (coax & optical) & AES/EBU
16-bit
yes
Marantz CDR500
XLR & Phono
S/PDIF (coax & optical)
S/PDIF (coax & optical)
20-bit
yes
Marantz CDR631
XLR & Phono
S/PDIF (coax & optical) & AES/EBU
S/PDIF (coax & optical) & AES/EBU
20-bit
yes
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2000), which is handy given its price.
The newest edition to Tascam’s range is the CD-RW4U built to
offer the features of the CD-RW700 mechanism in a compact
design. The front panel features a stereo mini headphone jack (with
level control), a program input level control and a VU level meter on
the LED screen for visual reference. The rear panel offers RCA
unbalanced analogue I/O and coaxial digital I/O. At $1,299 this unit
is well priced.
Tascam: (03) 9682 5886
Manufacturer: Marantz
Marantz, whether it’s in the studio or in the living room, has always
had a good name for their CD mechanisms. The
CDR631 features a good
amount of buttons and
controls on the front
panel (including chunky,
colour coded
‘stop/go/record’
buttons and a big
jog/shuttle wheel),
balanced I/O and is
designed for pro use.
Meanwhile the CDR500
is a bit different,
combining a CD player and CD
recorder with separate trays and I/O. The
applications for this are pretty obvious, as well as
useful in the studio.
Technical Audio Group: (02) 9810 5300/info@tag.au.com
standard CD-Rs to record 24-bit/96k audio, which has made it the
darling of many a mastering house. Furthermore, the Masterlink
has a hard drive on board, and a bunch of DSP functions to
sweeten your tracks before mastering them. There’s a full complement of I/O but no word clock input. Price: $4,299.
Electric Factory: (03) 9480 5988/mail@elfa.com.au
Manufacturer: Fostex
The Fostex CR300 has a good selection of I/O (although no word
clock input) and a healthy selection of features, which include four
CD-RW erase modes, three modes of copy bit selection and
support for FDMS (Fostex Disk Management System) data backup
from Fostex Digital Multitrackers – so a good choice if you own
other Fostex digital recording gear.
Syntec International: (02) 9417 4700
Manufacturer: Alesis
I haven’t included the Alesis Masterlink in the table below, because
it’s no regular CD recorder. Its claim to fame is being able to use
Fade in/out
Adjustable
gain on
Digital I/O
Remote
Text Writing
Syncro
Recording
Word Clock
Input
Price
no
yes
yes
yes
yes
no
$1,499
yes
yes
yes
yes
yes
yes
$2,399
yes
yes
yes
yes
yes
yes
$3,299
yes
no
yes
no
yes
yes
$3,495
yes
yes
yes
yes
yes
yes
$2,420
yes
yes
yes
yes
yes
no
$1,419
yes
yes
yes
no
yes
yes
$2,359
yes
yes
yes
no
yes
no
$1,640
yes
no
no
no
yes
no
$2,999
no
no
yes
yes
yes
no
$2,295
no
no
yes
yes
yes
no
$1,995
59