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 .
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?
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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. |
Yeah, a good DAC is where to put the cash. Ripping CDs to the hard drive is the way to go nowadays, apparently the checksum can even be done by comparing to values that can be found online (since lots of people are ripping the same CD). EAC is the classic choice for a Microsoft OS, and as for Macs there are some choices, I use XLD. |
An "error correction" concerning terminology :-) By definition, "error correction" CORRECTS errors in the data that is read from the cd, producing a bit-perfect result. That occurs routinely and frequently, with both computer data cd's and music cd's, and is performed by the cd drive electronics, invisibly to the rest of the computer or transport which the drive may be part of, and invisibly to the user, and with no adverse effects. What can cause adverse effects are errors that are severe enough to be uncorrectable. If the software or hardware that is controlling the drive does not make possible the multiple retries that have been mentioned above, or if those retries are not successful, the result may be (depending on that software or hardware) an indication of an error, a refusal to continue any further, a gap in the music, or "error interpolation," which is essentially a guess as to what the data should be, based on the values of nearby samples. If the cd and the drive are in good condition, those things will happen rarely, and certainly FAR less frequently than error correction. See this Wikipedia writeup, and note particularly this sentence: The result is a CIRC (Cross-Interleaved Reed Solomon Code) that can completely correct error bursts up to 4000 bits, or about 2.5 mm on the disc surface. This code is so strong that most CD playback errors are almost certainly caused by tracking errors that cause the laser to jump track, not by uncorrectable error bursts.Best regards, -- Al |
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