[skrivis]

While I agree that there should not be a difference between transports when using an outboard DAC (bits are bits, right?), I did hear a difference in my case.  The only rational explanation for my situation was that the actual digital reader was better quality with the Theta than the other DVD player (used as a transport).

I remember reading that although bits are bits, sometimes not all the bits can be read off of the disk and extrapolation occurs to fill in the missing data.  The better the reader the  ...

And where the difference between readers is negligible, but the cost varies greatly, they've thrown in lots of marketing to make up the difference.

Some of the expensive transports may be aesthetically pleasing with plush, thick front panels, or a weight of 150 lb. Ok, I can deal with that, but I am personally not going to pay for it.

We had a lot of players that were expensive, but still sounded like dung. Instead of admitting their implementation was crap, they came up with jitter as the culprit. Now, almost any evil is laid at jitter's doorstep.

I have failed to find any recent, unbiased information that shows that jitter is still a problem with modern DACs. (It would be nice to get a definitive answer from Frank about the AVA DACs though.)

Even with the older articles about jitter that started the whole thing, it doesn't look like it's a grossly obvious phenomenon. From what I saw, it was about in there with transmission line effects in a 10' speaker cable.

And the name is evil too. In telecomm, they call it timing slip. It has to be pretty gross before it screws things up. (ms, not ps or ns) But with digital audio it's jitter and I guess we're meant to be jittery about it. Too much coffee or something.

[TomW16]

And where the difference between readers is negligible, but the cost varies greatly, they've thrown in lots of marketing to make up the difference.  

I believe that we're both on the same page on this one skrivis.   In fact, with the advent of computer hard drives and players like the Slim Device Squeezebox, it will be increasingly harder to sell transports and CD players.  

Tom

[JeffB]

There are two possible sources of error as I see it.  Actual bit read errors and jitter.  Computer sources can read disks without any bit error, so why can't CD players?  Perhaps the computers retry, but if a CD player retried it would mess up the timing.  As for jitter, a DAC that buffers and reclocks the signal should solve that problem.  Perhaps DACs lacking this feature are affected by transports with jitter.  So what you want is a transport that either reads correctly or retries until it reads correctly and a DAC that buffers and reclocks.  Unfortunately finding such a DAC and ensuring that it truly reclocks accurately seems to be a problem.  Too many DACs take SPDIF input where the timing is in the input instead of external.  If the SPDIF signal is not carrying good timing then all is lost.  And where does the SPDIF timing come from, usually the transport.

So it is difficult to draw valid conclusing unless you know exactly what your components are doing.

[skrivis]

There are two possible sources of error as I see it.  Actual bit read errors and jitter.  Computer sources can read disks without any bit error, so why can't CD players?  Perhaps the computers retry, but if a CD player retried it would mess up the timing.  As for jitter, a DAC that buffers and reclocks the signal should solve that problem.  Perhaps DACs lacking this feature are affected by transports with jitter.  So what you want is a transport that either reads correctly or retries until it reads correctl ...

But I keep asking people about whether jitter is still a problem with modern DACs. Nobody responds.

First of all, a telling quote from Audioholics: "The amount of jitter that is really audible is something that is debated religiously and the psychoacoustics behind that is beyond the scope of this article."

Can it be heard? Nobody can agree on that.

Also from Audioholics: "What can make a difference in the sound of digital signal?  There are two major areas of concern: jitter (also known as clock phase noise) and data error.  Recently the use of improved buffering and local re-clocking (as opposed to clock recovery) of the signal have largely overcome jitter.  Ten years ago, however, jitter was the number one gremlin in the digital stew."

Everyone points toward some Stereophile articles from a decade ago. So there hasn't been any progress made since then? Maybe Stereophile hasn't made any progress since then, but the rest of the world has.

Jitter is a non-issue. They're trying to scare you with antique goblins. Trying to get your money based upon your superstition.

[miklorsmith]

Jitter, flitter.  Call it whatever you want, my dedicated CD transport unquestionably sounds better than my cheap DVD player.

Would I like them to be the same?  YES, then I could sell the CDP and free up a rack space.  Are they radically different?  No, a casual visitor might not notice the difference.  I can though, and that's all that matters.

Jitter may or may not be a red herring.  I think it's thrown out as a possible explanation for what people hear when listening to digital audio.

[skrivis]

Jitter, flitter.  Call it whatever you want, my dedicated CD transport unquestionably sounds better than my cheap DVD player.

Would I like them to be the same?  YES, then I could sell the CDP and free up a rack space.  Are they radically different?  No, a casual visitor might not notice the difference.  I can though, and that's all that matters.

Jitter may or may not be a red herring.  I think it's thrown out as a possible explanation for what people hear when listening to digital audio.

Then why don't they just admit they don't know? When I said I bought a $60 DVD player, people PM'd me and told me I was foolish because it want' as good. Oooohhhh, it has "jitter!" Failing to show it has increased jitter, further failing to show jitter is audible, and now admitting jitter may not even exist, what are we left with? "It's all in my mind."

I suggest you get a good DAC and then you won't need to worry about CD players or transports.

[avahifi]

All of our DAC devolepment work has been done on my 15 year old HK
cd player or my last running Magnavox unit that is even olderl

For whatever this is worth.  

New review review coming in next issue of - - - - .

Frank

[ricmon]

There are two possible sources of error as I see it.  Actual bit read errors and jitter.  Computer sources can read disks without any bit error, so why can't CD players?  Perhaps the computers retry, but if a CD player retried it would mess up the timing.  As for jitter, a DAC that buffers and reclocks the signal should solve that problem.  Perhaps DACs lacking this feature are affected by transports with jitter.  So what you want is a transport that either reads correctly or retries until it reads correctl ...

This thread is the exact reason I bought the Creek CD MkII.  Out of all the CDP/DAC topologies the fact that this CDP buffers and reclocks it's signal and is upgradeable via it's firmware I thought was the way all CDP should be designed.  Not ot mention it made Stereophile's reccomended componet list.

[jackman]

Jitter, flitter.  Call it whatever you want, my dedicated CD transport unquestionably sounds better than my cheap DVD player.

Would I like them to be the same?  YES, then I could sell the CDP and free up a rack space.  Are they radically different?  No, a casual visitor might not notice the difference.  I can though, and that's all that matters.

Jitter may or may not be a red herring.  I think it's thrown out as a possible explanation for what people hear when listening to digital audio.

I've been trying not to respond to this thread but your post prompted me so here goes.  My experience is exactly in line with your comments.  I tried several inexpensive DVD players and CD players as transports through the years and none sounded as good as a dedicated transport (an inexpensive CAL Delta) or a good CDP used as a transport (I've got a Modwright modded RAM from Response) in my current system.

I admit that I'm a cheapskate, and a HUGE skeptic when it comes to all things audio.  I could not believe how much better everything sounded when played through a better transport.  I can't explain the cause but the difference was staggering.  The better transport had improved bass, a more solid image and more natural overall sound.  It was an eye opening experience.  

People can choose to spend their money any way they wish.  I'm not in the transport business or audio gear business so it's no skin off my neck.  I will say one thing: if you have a decent system with a good dedicated DAC (like the ones from AVA) and don't hear a major difference between a decent transport (there are tons of really good ones available at very low prices on audiogon) and a $60 POS from Best Buy, you should sell the system, pocket the cash and live happily ever after with one of the many "Home Theater in a box" systems available for around a hundred bucks.  Better yet, spend the money on a thorough exam because you may have a hearing problem.  

I do not believe anyone in this thread who advocates a $60 transport over a decent one has ever made an actual comparison.  Ignorance may be bliss but not in this case.  Before you say I'm nuts, try to find someone in your area who will loan you their transport (or good CDP) to test in your system and hear for yourself.  

J

[tonyptony]

New review review coming in next issue of - - - - .

Frank

Frank, I've been following this thread mostly out of interest (but really not feeling like I wanted to chime in). Well, I'm chiming in now  You keep teasing us with the upcoming review(s). Can you tell us at least if it will be in an audio mag, a HT mag, or even whether it will be in a mag that is widely available across US stores like Borders and Barnes and Noble? (You can't find Audio Sense everywhere, for example.)

[avahifi]

major mag, found everywhere,

jitter, only jitter I am worried about is whether my hip replacemnt will go ok, kinda jittering about that now

cheep cd transports, no problem as long as error code implementation is done per spec, easy to do now

as long as I can sum and null a broadband white noise signal from the CD thru our DACs I figure it is likley working pretty well, and playback a full range square wave properly too, but that is another story, most DACs can't.

Frank

[tonyptony]

Can't wait for that review!

and playback a full range square wave properly too, but that is another story, most DACs can't.

Frank, could you expand on this? For those of us who know enough about engineering to kill ourselves   , what parts of these designs are typically at fault for this sort of thing?

[OTL]

I have several different CDP's, all supplying digital and analog outputs excepting the Cal Delta which is digital only.

- Cal Delta
- Pioneer DV-414
- hhb CDR-830 BurnIt CD recorder
- Radio Shack CD-3400 (requires phono to RCA adapter for Coax connection)

Observations, in no particular order:

- My mother can hear the differences between all the analog outs.

- All of the above sound quite different when feeding a bitstream to the Cal Alpha.  I much prefer the Delta as it's always relaxed, but the hhb is certainly no slouch, most likely more "accurate" it's just a bit to "sparkly" for my tastes.  It comes in a close second to the Delta.

- The DV-414 has "punch" but sounds "thin" and artificial by comparison.  Without a direct comparison a lot of folks could live with it.

- The Radio Shack player has a glorious midrange, but rolls off the treble too soon and has poorly defined bass.

- Each players overall "personality" comes across when making a digital recording on the hhb, though somewhat subdued as compared to direct digital playback. The resulting CD captures the "character" of the source.

- Lastly, but probably the most curious is that burning a CD copy on the hhb with the Delta as a digital source can actually IMPROVE the overall sound of the recording!  This does not happen in all cases, but on some CD's the difference is considerable and for the better.  More articulate bass, more precise imaging and a less offensive high end.  

I know all of these components are ancient history in digital terms, but the fact remains that a digital bitstream from each device sounds considerbly different when played back through my CAL Alpha or recorded on the hhb BurnIT CD recorder.

How can a bit-for-bit copy sound different?  I don't really know, but it's clear to me they do and this can be demonstrated anytime, on demand.

One last thought....why do Audioquest, JVC XRCD's and Mapleshade CD's always sound so damn good?

Listen, share and enjoy.

OTL

[skrivis]

I've been trying not to respond to this thread but your post prompted me so here goes.  My experience is exactly in line with your comments.  I tried several inexpensive DVD players and CD players as transports through the years and none sounded as good as a dedicated transport (an inexpensive CAL Delta) or a good CDP used as a transport (I've got a Modwright modded RAM from Response) in my current system.

I admit that I'm a cheapskate, and a HUGE skeptic when it comes to all things audio.  I cou ...

Ah, I see. I or my hearing must be at fault. How about if I suggest you have _your_ hearing checked?  

Or maybe my system isn't "high resolution" enough to show the difference. Yeah, that's what it must be.

[skrivis]

Can't wait for that review!

and playback a full range square wave properly too, but that is another story, most DACs can't.

Frank, could you expand on this? For those of us who know enough about engineering to kill ourselves   , what parts of these designs are typically at fault for this sort of thing?

If you pore over some of the old issues of Audio Basics, you'll get some idea of what the problems are. There was a fair bit of info on digital audio over the years in AB.

[jackman]

Ah, I see. I or my hearing must be at fault. How about if I suggest you have _your_ hearing checked?  

Or maybe my system isn't "high resolution" enough to show the difference. Yeah, that's what it must be.

Hey, if you actually listened to a couple transports, maybe you can make an intelligent decision or at least develop an informed opinion.  It's easier to just take other people's word for it and that seems to be the route you have chosen.  Too bad because I believe you might have been surprised by the outcome of a transport comparison.  I admit that my opinion was pretty similar to yours before I conducted a comparison.  It was enlightening.  

Cheers,

J

[skrivis]

Hey, if you actually listened to a couple transports, maybe you can make an intelligent decision or at least develop an informed opinion.  It's easier to just take other people's word for it and that seems to be the route you have chosen.  Too bad because I believe you might have been surprised by the outcome of a transport comparison.  I admit that my opinion was pretty similar to yours before I conducted a comparison.  It was enlightening.  

Cheers,

J

I listened to some of the CAL/Wadia/Theta stuff over a period of some years and was never very impressed. I have also compared an inexpensive player as transport to an expensive modded Marantz player, also feeding my DAC. I didn't hear any difference. The big Marantz was subjectively much nicer in terms of looks and feel, but it didn't sound any better.

Now, I did hear a large difference between my old Philips CD player and the new Philips DVD player, both feeding my AVA DAC. The new player seems to be much smoother and has no added harshness or sibilance. The old player was actually malfunctioning, and displayed skipping, repeating, and drop-outs. Even at the best of times it was sounding lousy.

If given a choice between a broken player and an expensive transport, I'll go with the expensive one. But when given a choice between a properly functioning inexpensive player and an expensive one, I'll take the one that will save me money.

The world has been using optical disk technology for long enough that properly extracting the datastream is not a problem. It can be done inexpensively and efficiently.

I guess I have two related points to make.

One is that it seems like too many audiophiles are concentrating on areas where they can only affect a miniscule change. Wire is a good example. Barring really abnormal configurations, you're dealing in really tiny differences at levels that have been shown to be non-audible.

There _are_ places where you can make huge changes. Your listening room, your speakers, and the speakers placement are all things that just absolutely swamp any changes in wires or fancy caps. They even swamp the differences between amplifiers and CD players.

Put your effort where it will be most effective. Ditto for your money.

So the other point is that people don't always get good value for their money. With the money I saved on my DVD player, I can buy a whole bunch of CDs. That makes far, far, far more difference to me than having the more expensive transport would.

Or I could buy a more expensive pair of Grado headphones and that also would make a much bigger difference.

Hey, I just signed up with yourmusic.com and I get CDs for $5.99 shipped. I can buy like 100 CDs with the money I saved on my CD transport. That gives me more music. Isn't that what this hobby is about?