New Transport Approach


With never-ending advances in technology and tumbling prices, I wonder if any high-end audio CD player manufacturer is considering an approach such as this - populate the player with 700 megabytes of RAM and pre-read the whole CD into RAM. We know this is completely reliable (or else our beloved MS Office wouldn't work). Then the whole transport system could be shut down, eliminating any concerns about mechanical or electrical noise, and the "CD" could be played back straight from RAM through the DAC. It would seem like this would reduce or eliminate jitter completely. There would be an "initialization" time penalty, but I would think for the high-end market, that wouldn't be a huge deal. Any thoughts? -Kirk
kthomas
From the Meridian website:

In the 800 Reference CD Machine, the audio data is read asynchronously in blocks using high-speed, high-integrity CD ROM drives. This data is checked for integrity, corrected and triple buffered to ensure that the audio output timing is independent of the drives for the first time.
Unfortunately Merridian has simply spewed some vague marketing terms. On more than one occasion I have found what I believed to be intentional misleading information. The worst was about "true" 24 bit machines. But not to stray here. What they've said really means nothing. Asynch vs. synch is often in how you defie it. In any case any CD / transport can claim asynch reads. Nothing to see here. The rest of that says nothing either. All CD players and transports check data for integrity, it's in the spec. Evereyone corrects the data, again in the spec. Dos it actually re-read the data if there's errors? It doesn't say. Triple buffering will prevent under-run. But again there's not enough detail to determine if they're doing something or if it's typical marketing BS.
I've been holding off buying a CD/DVD player for this very reason: I expect this read-from-memory to be about a year from now.

Meridian does do the seminal portion of this concept: its FIFO buffering through multiple processors allows multiple reads of the source, then actually pushes the music through the preamp from ROM. Perhaps, this is why they recently moved from a standard CD Transport to a computer CD mechanism.

Regardless of why; to me the when is more the matter. My recommendation is to NOT upgrade your CD/DVD player until this technology is here: it is an idea waiting to happen.
Even a cheap-o Sony Discman can buffer about 40 seconds, I think, of information into memory. I'm not an engineer, but it doesn't seem like it would be that difficult to read a whole CD into memory.
These methods are not new. They've just not been done with CDs. Two of my systems used this. One allowed you to preview CDs in the store and had tens of thousands of songs. Sampling was at 32kHz if I recall. Another system was used by a Jazz magazine to let people preview Jazz CDs over the phone. This had an even lower sampling rate and didn't sound too good. It was worse than MP3. There are different problems with CDs. You would think this would be simple but you end up taking a long time to load or you have to solve logistics problems when bit errors pile up and your buffer cache goes down. Nether one would be easy to push past marketing department.