This article is from the CD-Recordable FAQ, by Andy McFadden (email@example.com) with numerous contributions by others.
Start with the CD-DA FAQ [once at http://www.tardis.ed.ac.uk/~psyche/cdda/,
currently missing?] Take a look at http://come.to/cdspeed to see if your
CD-ROM drive is up to the task. EAC, from http://www.exactaudiocopy.de/,
is often recommended for extracting ("ripping") audio tracks.
To copy from CD to CD, the source drive needs to support digital audio
extraction, which is rare among older drives but universal in current
models. Ideally, the copy program will use disc-at-once recording to
produce a duplicate that mimics the original as closely as possible.
As with copying CD-ROMs, you must be able to read data off of the source
drive faster than your recorder is writing. If you can only extract audio
at 1x, you're not going to be able to do a CD-to-CD copy reliably.
If you're just interested in extracting digital audio, you don't even need
a CD-R unit, just a CD-ROM drive that supports Digital Audio Extraction
(DAE) and some software. The CD-DA sites noted at the top of this section
list drives that support DAE, have software to evaluate your existing
drive, and have links to several different DAE applications.
Different drives can extract digital audio at different speeds. For
example, the Plextor 6Plex can extract audio at 6x, while the NEC 6Xi can
only extract at 1x. Most recent drives extract at well over 20x, which
is about the limit for an IDE drive that doesn't support DMA.
Some CD-ROM and CD-R drives have trouble extracting digital audio at high
speed, so if you're getting lots of clicks and pops when extracting you
should try doing it at a slower speed. You may also run into trouble if
you try to extract faster than your hard drive can write. One user found
that he was able to eliminate clicks and pops by defragmenting his hard
drive. Another found that the Win95 "vcache" fix (section (4-1-2)) solved
It should be pointed out that, while digitally extracted audio is an exact
copy of the data on the CD, it's an exact copy as your CD player perceives
it. Different drives or different runs with the same drive can extract
slightly different data from the same disc. The differences are usually
inaudible, however. Some newer drives will report the number of
uncorrectable errors encountered, so you can get a sense for how accurate
the extraction really is.
The quality of the audio on the duplicate CD-R, given a high-quality
extraction, depends mostly on how well your CD player gets along with the
brand of media you're using. See the next section for some comments about
avoiding clicks and pops.
Some older drives have trouble starting at the exact start of audio tracks.
The extraction starts a few blocks forward of where it should, and ends a
few blocks later, so the track may not sound quite right and the extraction
program will report errors at the end of the last track. See section (4-19).
The Lite-On LTN483S 48x CD-ROM drive has a fairly unique bit of brain
damage: it doesn't extract the last two seconds of a track correctly.
This is only apparent on audio CDs with a "cold stop", where the music
plays right up to the very end of the track. If the track has two seconds
of silence at the end, there are no apparent problems. Apparently
there is a firmware fix for this (the PD03 update), available from
One minor note: the data on audio CDs is stored in "Motorola" big-endian
format, with the high byte of each 16-bit word first. AIFF files also use
this format, but WAV files use "Intel" little-endian format. Make sure
your software deals with the endian-flipping correctly. Byte-swapped CD
audio sounds like "static".