07-24-13: Zd542
I'm not sure I get that. I hear comments all the time stating computer audio sounds better than a CD player. Why? I don't understand how ripping a CD and playing the audio file on a computer would sound better than just using a CD player.
Playing a CD is not the best way to source a digital data stream intended for music. Any timing errors expressed as inconsistent spaces between the CD's pits enters the digital/analog converter and distorts the shape of the resulting analog waveform compared to the one originally recorded and digitized. Mass market CDs have jitter just from the stamping of the pits into the substrate. Then the disk is played back, usually on a not-very-rigid CD transport, often made of lots of flexible plastic. As the data stream is transmitted to the D/A converter, more jitter can creep in from reading and re-reading data, from varying impedances, etc. Ripping a CD to a computer hard drive eliminates these timing errors. New timing errors can occur from the hard disk read, especially if the music file is fragmented among several blocks scattered around the disk, but if the data is buffered in RAM all timing errors are basically reset to zero.
Compared to most CD players, a home computer can be a very powerful playback system, with a CPU whose cycles are measured in Gigaseconds, several Gigabytes of RAM that can be co-opted to buffer the data stream and stabilize it, thus removing jitter that might have accrued along the way. Finally the computer-sourced music files are sent to the DAC via an asynchronous USB link. USB, unlike S/PDIF, is a bi-directional link. It doesn't need the clock signal that comes down the datastream pike; it can generate its own freshly when it enters the D/A converter, making for a jitter-free conversion. This is a significantly different way to convert a digital music stream from the typical CD player.
In fact, for a very long time I've wondered why high end audio companies kept
resorting to expensive Herculean methods to lower jitter--diecast metal transports, thick faceplates, expensive vibration-reducing footers and damping materials, etc., when all they really needed to do was put a few megabytes of RAM in there to buffer the data stream and re-clock it. That's what the Genesis Digital TIme Lens (DTL) of the mid-'90s did--for $1195.
Founder Arnie Nudell used to cut demo CD-Rs to show off his speakers by playing the CD's data stream through his DTL before burning the CD. The resulting CD sounded better than the original and made his speakers sound better at the shows.
There is a wide variety of music playback computer software out there, and most of it is way cheaper than a CD player. I use Audirvana Plus on my MacBook Pro. With it I can configure Audirvana to freeze email and automatic backups so the CPU is never interrupted from playing music. I can reserve up to 8 GB of RAM to buffer the music files before decoding. This is especially helpful if you keep your music files on a USB hard drive. I also configure it to upconvert Redbook CD files to 88.2Khz and 48Khz files to 96Khz. If I ever get a 192Khz capable DAC I'll upconvert Redbook files to 176.4 Khz and 48 and 96Khz to 192Khz.
All these things can make the original digital file sound better on conversion, and most of these things are not available on CD players under several thousand dollars.
