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Today's Transport War: Significant Differences?

I have been reading much these days about computer/hard-drive based transports as being a whole order of magnitude superior to traditional CD transports. In my reading, the camp who believes hard-drive based transports can render major improvements has been most notably represented by Empirical Audio. The camp which suggests that traditional CD transport techonology (or atleast the best of its sort--VRDS-NEO) is still superior has been most notably represented by APL Hi-Fi.

Each of the camps mentioned above are genuine experts who have probably forgotten more about digital than many of us will ever understand. But my reading of each of their websites and comments they have made on various discussion threads (Audiogon, Audio Circle, and their own websites) suggests that they GENUINELY disagree about whether hard-drive based transportation of a digital signal really represents a categorical improvement in digital transport technology. And I am certain others on this site know a lot about this too.

I am NOT trying to set up a forum for a negative argument or an artificial either/or poll here. I want to understand the significant differences in the positions and better understand some of the technical reasons why there is such a significant difference of opinion on this. I am sincerely wondering what the crux of this difference is...the heart of the matter if you will.

I know experts in many fields and disciplines disagree with one another, and, I am not looking for resolution (well not philosophical resolution anyway) of these issues. I just want to better understand the arguments of whether hard-drive based digital transportation is a significant technical improvement over traditional CD transportation.

Respectfully,
pardales

Showing 3 responses by eclecticear

eclecticear
14 posts
 
Before jumping to conclusions about the Nova Physiscs Memeory Player go to their website www.thememoryplayer.com and read why their approach to get at the data on the CD is completely novel and does NOT resemble buffering, reclocking, oversampling, etc. Also remember that the Nova MP can only play back what has been recorded. It cannot reverse or correct any problems in the recording process and/or manufacturing stage. There is no DAC on this earth that can correct errors due to insufficient transport capability.
There are also two reviews out there on Positive Feeddback Online www.positive-feedback.com and The Stereo Times www.stereotimes.com
eclecticear
14 posts
 
Guys, guys, please let's keep the data straight.
The subject is alredy too technical for most us so let us not make things any more confusing.
I am referring to Drubin's comments on "Robert Harley's comments on the Memory Player" in TAS (Dec. 2006 issue, page 121). RH did NOT once refer to Read Until Right (RUR) in his comments. He DID made some very strong statements disputing the claims made by Nova Physics about CIRC (Cross-Interleved Reed-Solomon Code)error correction scheme, uncorrelated errors and error-concealment circuits. RUR is an extraction process used by Nova Physics to get the data off the CD and thus has nothing to do with CIRC.
Even if the claims by Nova Physics regarding CIRC are in dispute, their use of RUR and playing back from "flash" memory (and NOT the hard-drive) makes the MP a unique and technically superior digital playback component. Call it a transport if you wish, but it is a transport unlike any other.
eclecticear
14 posts
 
RUR is not nonsense. I am pretty sure Harley would also not call it that.
Instead of getting the data off the CD in a single pass, RUR reads the disc until a predetermined level of the total data on the CD has been extracted. In the case of the MP that level is 99%. This level is adjustable, but Porzilli found that going beyond 99% does not result in better audio performance. Besides that, going above 99% is far more time consuming. If I read it correctly, the RUR technique changes the angle of the laser pick-up when it finds data that is difficult to read.
RUR is also something that some in the recording industry uses to make sure that all the data is on the CD master.
You might want to refer to the reviews on www.positive-feedback.con and www.stereotimes.com. These people give some reasonable descriptions about the inner workings of the MP.
And lastly, why not go to the Nova Physics website at
www.thememoryplayer.com
If you really want an in depth discussion about the CD, get Ken Pohlman's book "The Compact Disc Handbook" 2nd Edition. I got mine from Amazon.com in the used book section. But be prepared to be overwhelmed. I never realized just how complex and sophisticated the inner workings of the CD really are.
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