Use a gDVD/CD player as transport with a good DAC?

A question for JC Audio and Hi Fi Farm- Did you try any DAC's with upsampling or re-clocking (re-sampling)?

There's a reason I ask. From the basics I know of DVD/CP players and transports, the digital output contains data with embedded clock. If the sound is bad then either the data is wrong (which doesn't seem likely) or the embedded clock has jitter (very likely). I know from my experience testing DAC's that jitter on the clock will definately affect the DAC's output, no matter how good the DAC. So my conclusion would be that a DAC with built-in PLL for re-clocking should clean up the jitter and the sound should be pretty good.

Of course, my engineering experience is pretty far removed from the world of high-end audio. That's why I value your expertise and experience. Also, I'm looking for a new CD player and wouldn't mind using my DVD as a transport if a good DAC would do the trick.

I maintain after trying many transports. Many of the differences we heard were with the transports with better power supplies. The DAC I use is the DAC 5 Signature from Audionote. At $49,500 it is awesome. As good as it is I hear huge differences when I move up the line in transports. As an example: AN makes a $999 transport which is much better than using a cd player or DVD players digital out. But if I move up the CDT-1 which is the same transport but with a larger power supply, Black Gate caps etc. the difference in the amount of information heard is unbelievable. If I move up another level with even better power supply etc. the sound isnoticeably improved again. I maintain that using a good transport makes bigger differences than moving up the same amount of money in DAC's. We have done it here many times. In fact a combination of a $2950 transport with a $1500 DAC sounds better than a $1000 transport with a $5000 DAC. We ahve done this shootout many times and the results are always the same. Every customer who has been in on the shoot outs has agreed. I would also say that if you are using a player or DVD you have never REALLY heard what your DAC is capable of.

Jcaudio,

Although I may agree with you that the transport does make a significant difference, your shootout in which you state "In fact a combination of a $2950 transport with a $1500 DAC sounds better than a $1000 transport with a $5000 DAC" is not a robust or valid enough test to prove anything as you are using two different DACs and two different transports. There is no constant that provides for a basis of comparison here, which means you are comparing apples and oranges. Although you may still be right, you cannot state that your shootout proves anything because there are too many variables(i.e. difference in performance between the two transports and DACs, the compatibility differences between each transport and DAC, the compatibility of all the units with whatever digital cable your're using, etc.). Given all those variables I could easily devise a shootout that would show just the opposite and state that DACs make a bigger difference than transports.

With regard to Dcaudio's initial question, although I currently use a transport/DAC combo if I were doing it again I'd probably go a different route and get a decent mid-level player(like a Sony NS500) and have it heavily modified by someone like Ric Schultz(www.tweakaudio.com--see this site for more thoughts on this issue), Dan Wright, Stan Warren, etc. This way you avoid the whole jitter/interaction issue and you also don't have to buy and insert another cable into your system, and it will probably end up costing the same or even less than buying a separate transport and DAC. Of course you lose the flexibility of being able to upgrade the transport or DAC, but with the evolving new formats and universal players on the way you'll probably want to completely overhaul your source within the next couple years anyway. Best of luck.

Tim

The comparison was done with transports and DAC's from all the same manufacturer. So compatibility issues are not an issue. If you would like me to state the models we used I would be happy to provide them. I thought I was pretty careful in stating the equipment was all from Audionote so someone wouldn't assume I was using incompatible equipment. If I wasn't clear enough I apologize.

That still doesn't address the fundamental problem with the way in which you are conducting the experiment. Just because you have found that with this particular combination of equipment you get the results you state does not mean you can extrapolate those results across all brands, models, and price ranges. Again, I'm not saying your contention that transports have more impact on sound than DACs is necessarily wrong(I tend to think they're both important), but you can't say it is always the case based on one example, and anyone who knows about statistical research methods will tell you the same thing. Your demo simply is not robust(in the statistical sense of the word) enough to support any broad or valid conclusions about whether transports or DACs have more of an impact on sound. As a counter argument, I could easily devise a demo showing DACs have more of an impact on sound than transports, but I still couldn't and wouldn't say that DACs are more important than transports--there are simply too many variables here to constitute proof one way or the other.

I think the only thing we can say with any confidence is that both DAC and transport(and the digital cable) are important to getting good sound, and as with audio in general the chain is only as strong as the weakest link.

Tim