2. digital
  3. 1311630964

how can a cheap cd drive equal a fine transport?

Once a "perfect" file is on a HD, I grasp why playback may be better than reading data from a drive in real-time. But when ripping a cd, the digital data stream is read by a cd drive, i.e, a flimsy, cheap transport. The best transports produce a data stream with less error, or jitter. Large amounts of error correction are audible, so presumably, the less error correction applied, the better. So at the point where the cd is read by a drive, before applying error correction, before it even reaches a HD (or the prior optimal solution, a Genesis Digital Lens), how can a cheap computer drive produce a data stream comparable to a good transport? How can programs which try it 64 times, or whatever, produce a better result? Aren't they just using error correction (or checksum algorthms to determine which attempt got the best result, out of many error-laden reads) compensate for high initial error rates? Are fine transports almost pointless, now?
128x128lloydc
elizabeth
6,726 posts
 
Programs like EAC let one know exactly how much error correction has been used to rip CDs. The vast majority of CDs have no error correction applied. And only damaged CDs seem to have it in the data.
So that side of it is clearly no correction is going on. One issue for CD players is the data is in real time. With a rip the data can be reread.
Even one new CD player has a buffer to hold the data instead of being in real time. (Ps Audio)
As for the reasons of all sorts of the issues between the PC hard drive, and CD transport... Not me.
lostbears's avatar
lostbears
479 posts
 

Computers work differently than CD or DVD transports. With a computer every bit must be right or a program will not run. When a computer program such as EAC rips a disc it reads the data over and over to get every bit correct. A program such as EAC can make a bit perfect copy of a disc. When you play a disc on a transport it plays as it is read. There is no rereading to get the bits right. If the transport can't read a bit it uses error correction to decide what the bit should be.

But computers are not perfect. They have a lot of RF and EM interference. They are also not built as well as a high end transport. Computers also need to be set up properly for audio to sound there best. That said I am not selling my high end CD player any time soon.
tmsorosk
1,013 posts
 
I recently upgraded from a Marantz SA11 to an Ayre C5Mp , both being used as transport's only , both were run into a Levinson DAC . The Ayre is leaps and bounds a better sounding transport . That being said , I have always felt the transport is at least as important as the DAC . Ernie Fisher used to preach the importance of the transport . So to answer your question , " are fine transports almost pointless now ? " yes , if you don't appreciate good sound .
shadorne's avatar
Ag insider logo xs@2x
shadorne
7,333 posts
 
Assuming a decent CD that can be easily read, then the transport can make a difference if the DAC operates as a slave to the transport clock. Only an asynchronous DAC (where there is no connection between clocks) will be totally immune from the type of transport used.

Only if the transport influences the DAC clock in some way can it possibly make a difference. So if a different transport makes a difference then it actually says more about the DAC jitter immunity than the transport.
More to discover