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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 4 responses by osgorth

osgorth
109 posts
 
Aplhifi: if I'm understanding you correctly, you're saying that a vibration/error free front end as you suggest reads different data from a disc than would a lousy CD-ROM drive in a computer? Has this been tested, e.g. is it possible to somehow capture the digital data from a such a transport and compare it to a standard rip from a CD-ROM drive on a computer? Now that would be an interesting experiment! :)

If they are indeed identical, what then is producing the difference in sound? You stated that jitter is not much of an issue anymore, what else could be a factor if we assume that the DAC is identical?

I'd really welcome a discussion on this, it's so hard for me to understand what the problem really is. It should be so simple I think, but demonstrably it isn't since I've too found significant changes between various CD transports connected to the same DAC using the same cable and playing the same disc. How is this possible?

Thanks!
osgorth
109 posts
 
>>playing back from "flash" memory (and NOT the hard-drive)

And the difference between these two are what, exactly? Both are digital storage devices. Both methods can easily handle the 1411kbps bitrate required for Red Book playback. Any differences perceived must be due to implementation artifacts, hardly due to the storage devices used.
osgorth
109 posts
 
Jsadurni: well, as Seandtaylor99 says, no matter which storage device you use, the data must hit the RAM first, since that's the only way to retrieve data off a hard drive, a flash card or whatever. They work as storage devices, so you read from them into a RAM buffer, and then you can forward it to the DAC or whatever you wish. :)

That's what I meant; I can't for the life in me understand how different storage devices would sound differently. IF there is a difference, it's got to be due to the implementation, e.g. what happens to the bits after being output from the RAM buffer.
osgorth
109 posts
 
Yeah, please Alex (or anybody), can you explain this? I'm lost! :)

I do understand that CD transports differ because data and clock is being transmitted in real time and are so suspectible to jitter. But reading from a storage device such as HD or Flash cards isn't done in realtime eh? The way I see it data is fed into a RAM buffer packet-wise as is normal in any computer, and clocked on the way out to the DAC - is this not so? If not, why not, and how is it done instead?
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