Can different CD *transports* sound different - when fed into the same DAC?

[MattHooper]

Yes we could. And it would be complete waste of time. Each player will have no effect on the output of the DAC. There may be some low level jitter differences, but nothing remotely audible despite the hoopla at times in the hifi press. FR and all of that will be unchanged by which transport is used. I've done this before with a handful of transports and trust me don't bother. It does not make sense it would matter if you know how this works, and in practice it also does not matter. If you are spinning discs, use the transport that you can afford, with features you want and don't worry about it.

If you are listening directly to the player then there can be FR differences which might account for slight sound differences. They usually are not largely different.

I'm curious about something Blumlein 88:

I've mentioned before that in the 90's I did some blind testing between 2 CD players and a DAC - A Sony CDP, Meridian CDP and a Museatex Bidat DAC (with it's own volume control). I was able to level match at the speaker terminals using a voltmeter for the blind test. I found it very easy to identify which I was listening to, especially the Meridian and Museatx DAC. (The DAC sounded slightly darker, more lush, seemingly a bit deeper bass, slightly more diffuse and larger image, vs the tighter focused imaging of the Meridian, and the Meridian's slightly more upper mid/lower treble forwardness and texture).

If we take the results as valid, for sake of argument, any speculation as to where in the design sonic differences could occur? Analog stages? Digital filters?

 

[Robin L]

My personal experience: My Sony BDP BX-57 Blu Ray player used as a transport sounds fantastic for a piece of audio gear that set me back all of $8. I'm using an optical link to a Topping E30 DAC. Interestingly enough, my single layer SACDs play through the outboard DAC, though not too surprisingly the few Blu Ray audio discs do not. There is enough difference between recordings, including DDD productions, to indicate that this data/signal chain is imposing very little (if any) of its own colorations on the resultant sound. Now, this Blu Ray player is one of the less expensive players, has analog outputs (which I don't use) which indicates it is one of the older players. Bought it used. It's worked well for the four years I've owned it. I really don't think there's a correlation between sound quality and cost for properly functioning digital gear.

 

[Wseaton]

I've heard differences in line leveled DAC's, particularly the late 90's and early 2000 that were liked getting kicked in the head. We did A/B/X comparisons with people who admitted they had wooden ears and even they could easily spot the differences and double blind confrm what DAC was what. The dual Burr Brown based transports and in higher end Receivers were worth the extrae money and set the break out point for diminishing returns, IMO.

If we are talking about pure transports 'sounding' different then one transport isn't properly applying Red book standards and and not properly trasnmitting data. This doesn't require subjective listening tests. Simply capturing the data in the bitstream or doing a RIP will show inconsistencies in the final data being sent.

Audiophiles have caught onto this with their slippery arguments and have moved the issue to the time domain. As I understand it DACs have their own clock and don't care about bitstream clcoking or jitter. The back room argument is that sound issues with trasnports are caused by clocking issues between the trasnport and DAC, and that 'high end' transports do a better of job of clocking. Sounds like reptilian petroleum to me, but looking for official technical debuking. Anyone?

 

[Blumlein 88]

I'm curious about something Blumlein 88:

I've mentioned before that in the 90's I did some blind testing between 2 CD players and a DAC - A Sony CDP, Meridian CDP and a Museatex Bidat DAC (with it's own volume control). I was able to level match at the speaker terminals using a voltmeter for the blind test. I found it very easy to identify which I was listening to, especially the Meridian and Museatx DAC. (The DAC sounded slightly darker, more lush, seemingly a bit deeper bass, slightly more diffuse and larger image, vs the tighter focused imaging of the Meridian, and the Meridian's slightly more upper mid/lower treble forwardness and texture).

If we take the results as valid, for sake of argument, any speculation as to where in the design sonic differences could occur? Analog stages? Digital filters?

I don't see any of your sources having audible noise. I don't see them having audible distortion. My best guess would be frequency response in the upper octave or two caused by the filters in use. Or the volume control causing FR differences depending upon how it was done. That Bidat would have been a Bitstream DAC.

 

[antcollinet]

Sounds like reptilian petroleum to me

Does to me too.

CD transports buffer the data from the disk and clock it out of the buffer with a stable clock.

As long as that clock is sufficiently stable** to allow the DAC to lock onto the incoming data stream (and do it's own buffering and clock recovery|) then competent dacs are able to reject any incoming jitter to well below audible levels.


** and if it isn't then the problems won't be subtle - there'll be buffer over-runs/under-runs, generally resulting in dropouts in the audio, or just no audio at all.

 

[Vacceo]

I do have a measurement mic - still in the box lol

it's a lot of bother to find out what I already know. Plus the perceived difference is very small, unsurprisingly.

I could not tell the difference between the TEAC transport and same CD copied to drive and played back on an X50D streamer - when single blind.

Digital is pretty consistent and stable is my conclusion.

Even if the answer is "psychoacoustics", I'd wonder what levers, exactly, are involved. Pure curiosity, yes, but I agree it is a lot of work for something you know the outcome.

 

[Mart68]

Even if the answer is "psychoacoustics", I'd wonder what levers, exactly, are involved. Pure curiosity, yes, but I agree it is a lot of work for something you know the outcome.

whenever I see subjective rankings of transports, DACs, CD players, streamers - it's almost always most expensive best and least expensive at the bottom. So I suspect just knowing the price plays a major role.

Added to that - reviews you have read, the specs, the back-story, the measured performance, liking the appearance, liking the brand, perceived build quality, what people on forums or friends/cronies say about it.

 

[aagstn]

whenever I see subjective rankings of transports, DACs, CD players, streamers - it's almost always most expensive best and least expensive at the bottom. So I suspect just knowing the price plays a major role.

Added to that - reviews you have read, the specs, the back-story, the measured performance, liking the appearance, liking the brand, perceived build quality, what people on forums or friends/cronies say about it.

A friend of mine was trying to sell me on the Cambridge CD player he bought a couple of years ago over the old stuff I use. I'm sure the Cambridge is a fine player, but I have no interest in spending that when what I have works fine. He is sold on the more expensive sounds better thing. I told him I bought a gold plated toslink cable so I should get enough improvement from that to be good.

 

[Platypus20]

New Cambridge CXC v2 transport arrived, I really did not hear any real difference, using the cheap Sony dvd player. The only real difference was no track info, as the dvd player has no screen or panel lights

 

[CleanSound]

.The fact of the matter is that a more resolving system, particularly speakers, "resolve" more transparently audio information. If you don't think that is true, then, i have no reason to even argue about that ). However that can be easily observed when one goes from a budget to a mote hifi system.

When someone claims you can't hear the difference because your system is not "resolving enough," I always ask them to define "resolving" and what makes it "resolving," is the pricetag the measure of level of "resolvingness?"

 

[Ricardus]

When someone claims you can't hear the difference because your system is not "resolving enough," I always ask them to define "resolving" and what makes it "resolving," is the pricetag the measure of level of "resolvingness?"

I usually mock them when they say that to me. I usually say something like you did and then have fun with it:

"What isn't my most excellent system resolving? Is it forgetting to reproduce the bass notes, or the piano parts? And is it doing it on purpose? Like out of spite??"

 

[Brian Hall]

After reading this thread, I had a couple of friends come over and we did a small "mostly blind" test (had a sheet hung up between the couch and the equipment). Two of us listened and the other did the switching. I wore my hearing protectors I use when target shooting with various loud guns to try to keep from hearing the differences between inserting the CD in each drive.

Tested my Audiolab 6000cdt, my Onkyo c-7030, an old Sony 4k blu-ray player, a cheap USB dvd drive plugged in to the external disk port on the Eversolo dmp-a6 and playing the same song as a ripped lossless flac from the dmp-a6's ssd.

All used a coax cable into an eversolo dac-z8 for easy switching. Audio out from the dac uses the excellent Amazon Basics rca cables goes to a Sony AVR (STR-DH790) with that input set to 2 channel stereo. The song for the test was Alison Krauss's "Losing you", first song from her "Windy City" CD.

I really tried to listen for any difference. Neither myself or my friend could tell any difference with the 4 "transports" or the ripped flac.

That makes sense since all were just sending bits to the same dac with output to the same AVR. The speakers for the left / right channels were a pair of Klipsch Reference R-26FA floor standing speakers.

All sounded great to me. I don't have any measuring equipment so that was the best test I could think of with what I had access to. I do have to give credit to the Audiolab transport for being able to play a couple of old cds that skip a bit on the Onkyo. It is a good functional transport priced at $499, but it doesn't sound any better than the $35 USB dvd drive.

What would be needed to capture the digital coax output from cd transports/players to disk files that can be compared?

 

[voodooless]

What would be needed to capture the digital coax output from cd transports/players to disk files that can be compared?

Just any old audio interface with a coax input.

 

[GXAlan]

I do have to give credit to the Audiolab transport for being able to play a couple of old cds that skip a bit on the Onkyo. It is a good functional transport priced at $499, but it doesn't sound any better than the $35 USB dvd drive.

^^^ This.

Most DACs do pretty well and most transports do pretty well where you don’t run into jitter or transparency issues that fail to come very close to the theoretical limit of CD.

Responsiveness of reading the “table of contents”, responsiveness of the remote to switch tracks, displays, drive noise both in use and during loading, are the biggest differences.

For SACD, some transports will decode to PCM (like Sony blu ray players). Others can decode to an encrypted DSD stream in case (Accuphase, which has transparent DACs at high prices, and PS Audio which doesn’t have transparent DACs).

But having owned an expensive Marantz SA-10 and now just using the Sony X800M2, you do notice a difference in the drive construction and I believe I hear subtle improvements with the SA-10/PM-10 versus X800M2/CX-A5100, but once you include the speakers, the drop in performance with cheaper electronics that lets me spend more money on speakers translates into better end performance.

For a while, I did use the SA-10 to Schiit Freya in passive mode to my Meyer Amie and it was wonderful.

 

[BobbyTimmons]

All sounded great to me. I don't have any measuring equipment so that was the best test I could think of with what I had access to. I do have to give credit to the Audiolab transport for being able to play a couple of old cds that skip a bit on the Onkyo. It is a good functional transport priced at $499, but it doesn't sound any better than the $35 USB dvd drive.

What would be needed to capture the digital coax output from cd transports/players to disk files that can be compared?

To make the test single-blind you shouldn't have known what component was being switched out. You already knew it was going to be the transport so you knew everything would sound the same before the test began.

 

[Brian Hall]

To make the test single-blind you shouldn't have known what component was being switched out. You already knew it was going to be the transport so you knew everything would sound the same before the test began.

The point was to test my available CD transports and players to see if there was any noticeable difference in sound. And of course I expected them to sound the same because they are all doing the same thing. Anyone with a working brain should expect them to sound the same. Bits are bits.

All I could do was eliminate the effect of seeing and knowing which one was playing the song.

 

[BobbyTimmons]

The point was to test my available CD transports and players to see if there was any noticeable difference in sound. And of course I expected them to sound the same because they are all doing the same thing. Anyone with a working brain should expect them to sound the same. Bits are bits.

All I could do was eliminate the effect of seeing and knowing which one was playing the song.

It's not a even single-blind listening test so it isn't evidence. If you wanted to test if there was any noticeable difference in sound you would need to blind the listeners from what components are being changed if any

 

[CleanSound]

It's not a even single-blind listening test so it isn't evidence. If you wanted to test if there was any noticeable difference in sound you would need to blind the listeners from what components are being changed if any

I don't think it was meant to be a scientific proof to anyone, it's an experiment amongst friends and guess what? They didn't hear a difference.

 

[Brian Hall]

I don't think it was meant to be a scientific proof to anyone, it's an experiment amongst friends and guess what? They didn't hear a difference.

Exactly. How can you test transports/cd players without knowing you are doing it. We didn't know which one was playing. Every component was the same except for which one was playing.

My expectation bias was that there would be no difference. I could not change that, but my friend did not know that.

Was I supposed to test a transport against a turntable or a cassette deck?

 

[antcollinet]

It's not a even single-blind listening test so it isn't evidence. If you wanted to test if there was any noticeable difference in sound you would need to blind the listeners from what components are being changed if any

No, double blind doesn't mean that. Double blind means the person administering the test doesn't know which of the devices is playing - so that he can't pass on any tells to the listener.

Single blind means that only the listener doesn't know.