[MKAL]

I am wondering if the transport affects sound signature (bright, warm, etc.), or if the only thing the transport affects is jitter? Would a $100 DVD player as transport be destroyed by a $200 CD player as transport? Basically, I am considering buying a Micro Dac or TubeDac and am wondering if I should keep my $100 DVD player as the transport, or if I should upgrade this piece as well? If an upgrade is in order, please offer some good, cheap solutions ($100-200) for a CD playing transport.

 

[kontai69]

My understanding is that it's the jitter signature of a transport that confers its sonic signature when used to feed a DAC. I'm using a Sony DVP-NS775V DVD Player ($100 at Best Buy!) to feed an Ack! dAck! 2.0 D/A converter www.ack-industries.com . There was a noticible difference between the Sony and an old NAD 502 CD player when using the coaxial digital output on both. The Sony as a transport has greater treble extension and a slightly more forward presentation. However, the bass was a little "bloaty" with less articulation when compared to the NAD. I like using a DVD player as a transport because I can use one box to watch movies and listen to music. Less clutter.

You may also want to check out this thread...
http://www6.head-fi.org/forums/showt...ght=ack%21+nad

 

[Sleestack]

I run multiple digital sources through an external DAC. To be honest, I can't tell the difeerence between 2 CD players (i.e. XCD-88 and Denon 3910) going through the same DAC. I'll be getting a $3500 Meridian GO8 in a few weeks. I'm not going to be using the digital out, but I will test it throuugh my DAC to form my own opinion on the matter.

 

[PhilS]

Quote:

Originally Posted by MKAL I am wondering if the transport affects sound signature (bright, warm, etc.), or if the only thing the transport affects is jitter? Would a $100 DVD player as transport be destroyed by a $200 CD player as transport? Basically, I am considering buying a Micro Dac or TubeDac and am wondering if I should keep my $100 DVD player as the transport, or if I should upgrade this piece as well? If an upgrade is in order, please offer some good, cheap solutions ($100-200) for a CD playing transport.

I think a general answer as far as a transport's effect on sound is that it may depend on how good the DAC is, how good the transport is, and how good the rest of the system is. Thus, I'm not sure one would hear the difference between a $100 DVD player and a $200 CD player with anything but a real good quality DAC, and there's a pretty good chance you would not hear it even then. I'm not saying there is an absolute certainty you won't; I just would not be surprised if you didn't hear any difference. On the other hand, there seems to be a general consensus (or at least numerous reports) that with DAC's in the $1000 range and on up, improving the transport can make a subtle difference. It seems that the transports under consideration, however, are generaly in the range of $500 and on up.

The bottom line is that you won't know until you try it, but I would not expect significant improvements in the price range you're talking about. I would also buy on return, so you can send the CD player back if it doesn't offer you what you had hoped for in terms of an improvement.

 

[Slow_aetk]

If you have a good, reclocking DAC, and a decent 75ohms digital IC, you should not be getting any jitter related differences between two transports.

Now comes in play the integrity of the digital bit stream. IMO this depends esssentially on the quality of the disk reader mechanism and electronics. As even hi-end systems are using rather common philips, pioneer or others, reader subsystems, I' don't see what could be so different between two "working" transports!?

What else?

 

[braillediver]

“$100 DVD player and a $200 CD player”

At this level of players the difference is probably features not fundamental components.

So there probably wouldn’t be any audible difference.

Now if you were comparing a $100 player to a $1000 player then there would be differences in the type of transport and internal circuitry.


Mitch

 

[Jon L]

Most CDP/DVD players these days under say $1500-2000 use pretty much similar transports, the ubiquitous and cheap Philips CDM12 for CD transports and the VAM types for DVD players. These are mass-produced, cheap plasticky mechanisms, and while one can try to optimize them with better implementation downstream, one can only do so much.

This is why many cheaper CDP/DVD players sound similar used as transports.

A great transport takes extreme engineering, $, and implementation. Often this involves the "obsolete" but superior older Philips transports such as CDM2Pro, etc. In a recent survey of Philips engineers, the very original CDM1 was voted the "best" transport they ever designed. A great chassis, vibration/resonance control, extreme jitter reduction, immaculate digital path with hopefully "proper" digital out (I2S, "laserlinque," Meitner 3-wire optical, etc) is necessary. It only takes a few seconds of comparison between a great transport and a $200 CDP to realize the HUGE importance of transports.

Some newer players are trying to "cheat" the above obstacle by employing a large buffer between transport and DAC section, such as the new Cary 303/300 which uses DVD-ROM as mechanism and the APL modded Denon 3910. But even then, you are trying to capture digital data with a puny laser off of a rapidly-spinning CD with all kinds of servo correction in real time while the entire room and chassis is vibrating from various mechanical micro-vibrations and speaker vibrations.

A "better" way would be hard drive w/ bit-perfect copies, spitting out digital data via USB, ideally asynchronously, into a outboard DAC that will faithfully convert USB stream to I2S before DAC chips. There's no off-the-shelf solution for this method so far, though.

 

[Leporello]

Quote:

Originally Posted by Jon L But even then, you are trying to capture digital data with a puny laser off of a rapidly-spinning CD with all kinds of servo correction in real time while the entire room and chassis is vibrating from various mechanical micro-vibrations and speaker vibrations.

Yes, we certainly are trying - and succeeding quite brilliantly. That is the beauty of digital.


Regards,

L.

 

[clarke68]

Quote:

Originally Posted by Slow_aetk If you have a good, reclocking DAC, and a decent 75ohms digital IC, you should not be getting any jitter related differences between two transports.

I agree, although even reclocking is a bit of a "band-aid" solution. One could argue that if you can hear differences between transports, cables, etc. then the DAC's design is faulty. That said, the reality is that 95% of the DACs on the market are faulty, so we're stuck with transport differences.

The best article I've read on the subject is A Transport of Delight, from a 1993 issue of Stereophile.

 

[erickoh]

Some DVD players may not have bit perfect digital-out.
My own DVD-Recorder/Player seems to have its own internal mixer.
Its other inputs include the RF-In and the karaoke mics.

At any rate, the digital out from my dvd recorder/player sounds worse than that from my HTPC.

 

[shimage]

If you have an uber-crappy transport that doesn't even send the right bits, then that could be a problem too, though I usually don't hear people worrying about it.

I was gonna say that I thought the Headroom DACs used an AD1896, which when used properly should give you pretty good jitter rejection, but evidently that's only in the Max DAC = not cheap ... I don't know anything about the Tube DAC (though it looks like it uses a receiver), so I won't comment on it. If you don't reclock, then you're a victim to jitter, but DACs that reclock properly may not be in your price range...

Quote:

Originally Posted by clarke68 One could argue that if you can hear differences between transports, cables, etc. then the DAC's design is faulty.

or—provided that the DAC is designed right—one could argue that placebo is not being properly accounted for. That said, the reality is that 99% of the comparisons out there do not account for placebo.

 

[Slow_aetk]

Quote:

Originally Posted by clarke68 I agree, although even reclocking is a bit of a "band-aid" solution. One could argue that if you can hear differences between transports, cables, etc. then the DAC's design is faulty. That said, the reality is that 95% of the DACs on the market are faulty, so we're stuck with transport differences. The best article I've read on the subject is A Transport of Delight, from a 1993 issue of Stereophile.

Your're right, outstanding article. Thanks for the pointer. It is the first paper on transport jitter, and 12 years later still the best!?

It clearly shows that reclocking can not only reduce jitter but also increase it (if the transport has very low jitter), sustaining my opinion that all "working" transports should sound the same connected to the same "reclocking" DAC. Their jitter caracteristics reduced to that of the DAC's world clock.
Modders are right when they mod DAC's clocks with very precise (<10ps) ones.

 

[Yikes]

I know it's uncool to quote myself but this post tells a story that might be of interest.

Quote:

Originally Posted by Yikes I am not counted amongst those that believe that computers make good sources for true high performance audio systems. It is difficult to find a dirtier (Electrically) environment than that which exists inside a computers case. Using a computers digital out (I have done this) to drive an external D/A converter may result in excellent sound, but the question is: Would using a quality external transport result in even better sound? CD or to be more precise DVD Rom drives can make exceptional transports. There are at least a couple of high-end companies that have started using computer type drives for their transports. Five years ago or so I was of the belief that the CD transports performance only accounted for 10-15% of the sound quality and that the D/A accounted for 85-90% I then had the opportunity to do a detailed comparison between two different transports (DVD players being used as transports), both driving the same D/A and using the same cables and other electronics. The D/A was the EAD DSP-9000 (great DAC if you ever find one used) The transports were: Arcam DVD player (I believe it retailed for around $1800, and it was highly regarded) Meridian DVD player ($4200) Using the Arcam the system sounded very good, I really couldn’t imagine how the Meridian could justify the increase in price when considered solely as a transport. Boy was I ever mistaken; the Meridian absolutely smoked the Arcam. It wasn’t subtle. With the Meridian the sound was better in every conceivable way. The difference was huge, more along the lines of changing amp and preamp sets, or almost like changing speakers (but not quite that much). My point is that good results can surely be had using a computers digital out, but that a quality external transport will likely offer a much higher performance plateau. I don’t know if the current crop of NAD players would qualify as a “quality” external transport. I like the NAD players they offer a lot of bang for the buck, but are they good enough (as a transport) to make a sizable improvement? I don’t know.

 

[jpelg]

Interesting post (and quote

) Yikes.

I don't dispute what you heard. I (and presumably the thread starter) am just curious as to why, specifically, it happens?

 

[fewtch]

IMO it's hard to tell what's going on vis a vis transports, since CDP's with high end transports also tend to have high-end parts quality and design as well (and vice-versa with CDP's/DVDP's using cheaper transports).

I've had to make educated guesses which take all the various factors into account, but have concluded that there aren't any significant, impactful differences between inexpensive/good and expensive/hi-end transports. Yes, there are major differences when comparing a downright crappy transport (like in a crummy cheap PCDP) and a quality transport, but I believe once a basic level of quality is reached, further sonic improvements become questionable. Just MHO, as always.