.

[eliash]

As an engineer I have always been sceptical of the VRDS idea. I think it is cockeyed thinking, or marketing linked to record player mythology.
Clearly keeping the disc flat will reduce some laser servo activity. Unlike an LP, however, a CD is constant linear velocity source, and spinning relatively fast too, so anything increasing the inertia of the disc will increase the servo power required to keep the frequency right on an eccentric disc.
There is literally zero benefit in increasing the inertia of a CD, the opposite in fact.
No idea if any of this could be the cause of your weird artefact though.

If I remember correcty, it was thought to reduce radial runout and firm fixing of the disc to the spindle...but one could probably call it overkill, from my perspective...

 

[Angsty]

Without wanting to bore you, there are phenomenal differences in transports, CD players and computer based drives in that respect.

Please bore me! I have the opportunity to replace my old CD player with a newer transport and I’m trying to determine how I would really know if the newer one is better performing or not. I’d like to avoid inherent bias for the new shiny thing.

I understand some of the mechanical and electronic differences, I just don’t know how I would find measurements for output quality.

In lieu of measurements I could perform or find, what have been the units you have found to be best performers?

 

[solderdude]

Some CDP's have excellent tracking and focussing abilities and can easily 'bridge' black dots up to 0.8mm or even information layer interruptions of that size (on the left in the picture).
The picture below is of my Technics CDT-016 test disc which can be used to check/adjust tracking and focussing of the laser assembly.
The biggest dot and data-layer interruption is 0.9mm on this disc. Most well adjusted mechanisms could reach 0.8mm.

There are quite some differences between mechanisms and how they handle such errors. Its amazing how much data can be lost without you even hearing it. Some brands/mechanisms are better than others and that's what @restorer-john is talking about.
To determine performance you either need crappy discs or specialized discs as shown above otherwise you can never tests for this.

 

[Hipper]

From the TEAC P/70 manual:

The VRDS (Vibration-Free Rigid Disc-Clamping System) assembly.

https://www.manualslib.com/manual/616744/Teac-P-70.html?page=4#manual

https://www.manualslib.com/manual/616744/Teac-P-70.html?page=22#manual

 

[solderdude]

Owners manuals tend to be filled with ... well... the same nonsense as advertisements.
The service manual would be more interesting.
In the end it's the laser lens's quality, servo's and its electronics that truly determine how well the eye pattern comes out and the track is followed despite numerous influences from outside trying to throw it off.

 

[Angsty]

Its amazing how much data can be lost without you even hearing it.

That’s a true and interesting point. Audiophiles can spend a lot of time ripping CDs to FLAC files, but can we be assured that the FLAC files contain ALL the data? I’ve had the experience of hearing anomalies in ripped files from crappy discs.

I recognize that computer CD drive software
functions a bit differently than that of CD players. Given that, would one expect FLAC files ripped to a computer to be superior in data integrity to the data stream from a CD transport? Not to say we could really hear the difference, though.

Nonetheless, in considering a transport purchase, I’m interested in the transport that gets the most data off the disc and delivers it most accurately to my DAC. Aside from ergonomic and reliability issues, too.

 

[jhwalker]

That’s a true and interesting point. Audiophiles can spend a lot of time ripping CDs to FLAC files, but can we be assured that the FLAC files contain ALL the data? I’ve had the experience of hearing anomalies in ripped files from crappy discs.

Use a ripping software that includes AccurateRip checking - this compares your rip against an online database. If your rip matches even 1 online rip, you're virtually guaranteed a perfect rip. If it matches 2+, it IS guaranteed - there's really no chance you could have 2 or more CD players deliver the EXACT same bits in the exact same order and yet be "wrong"

 

[solderdude]

When a CD is damaged to a point where the tracking/error correction cannot retrieve the data this is noted in the log that is generated and a thousand re-reads (which isn't happening in CDP) can't improve the rip.
A 'better' mechanism/transport may well retrieve more info.

I am no expert in how ripping software works and thus don't know how C1, C2 and CU errors are handled as well as how good interpolation will work when CU (unrecoverable errors) are handled and how that would lead to which kind of sound degradation. One would expect audible ticks, crackles etc. C1 and C2 errors are quite common and fully correctable in both CDP and ripping software.

When you hear anomalies this must be visible in the rip data and the solution would be to either use another drive, get a better CD or clean the CD and rip again. Quite possible a CDP would have no problems with the disc or the other way around. A CDP would not play it correctly but a rip would still be possible. In this case it all comes down to tracking/focusing and retrieved eye-pattern as well as the used electronics/drive of the laser mechanism.

 

[Angsty]

Use a ripping software that includes AccurateRip checking - this compares your rip against an online database. If your rip matches even 1 online rip, you're virtually guaranteed a perfect rip. If it matches 2+, it IS guaranteed - there's really no chance you could have 2 or more CD players deliver the EXACT same bits in the exact same order and yet be "wrong"

Thanks - the last time I ripped files was several years ago on an old Mac using iTunes. I could get the FLAC file that way, but it wasn’t fancy. Today, I mostly either spin discs or stream music from an online service.

So, I’d interpret from the response that a ripped file data stream can be quality checked in a way that is hard to replicate with a real-time CD transport.

 

[Doodski]

As for the alignment and defects discs, they cannot be duplicated as they are verified optically flat, concentric and contain various pressing (deliberate) defects in the data stream ranging from burst dropouts, continuous and repeated incremental length dropouts, changes in track pitch, length and eccentricity.

I'm very familiar with the Sony YEDS standard reference disc and the Philips example shows the disc deliberate defects that are very handy for proving a machine is up to specification. (For the peeps that have never seen these types of calibrated discs before.)
http://www.cieri.net/Documenti/Misu...ilips - Test Sample 4a - 410 056-2 (1982).pdf

 

[restorer-john]

I'm very familiar with the Sony YEDS standard reference disc and the Philips example shows the disc deliberate defects that are very handy for proving a machine is up to specification. (For the peeps that have never seen these types of calibrated discs before.)

I also have the Philips 3 disc set here. Ironically, the defects are printed onto the disc and are themselves very easy to damage, whereas the Pierre Verany defects are in the data stream itself. Already these discs are beyond rare, letalone ones in absolutely unmarked condition (very important).

 

[Doodski]

I also have the Philips 3 disc set here. Ironically, the defects are printed onto the disc and are themselves very easy to damage, whereas the Pierre Verany defects are in the data stream itself. Already these discs are beyond rare, letalone ones in absolutely unmarked condition (very important).

We were servicing enough volume that ordering in fresh Philips and YEDS disc every 3 months was not unheard of. When servicing that many CD units the calibration standards take a beating and require replacement. Gotta have factory gear for factory service.

 

[Harmonie]

Use Pioneer DV-300 (DV-393, DV-610 or similar) as CD transport with small improvement
http://lampizator.eu/LAMPIZATOR/REFERENCES/Goldmund/goldmundizator.html

I use a (Teac based ?) transport; the 25 year old EAD T-1000 and still enjoy it very much !

 

[Angsty]

The founder of PS Audio has an opinion...

 

[Dialectic]

The founder of PS Audio has an opinion...

As he is on so many subjects, Paul McGowan is again just wrong here. To save you the trouble of watching the video, McGowan says that, if you have a system without much "resolving power," the CD transport will not make a difference. However, if you have a system with a lot of "resolving power," McGowan asserts with no basis, you will be able to hear differences among transports.

If we set aside questions of error correction quality, conformance to the redbook standard, durability, etc., and focus exclusively on audio quality, the only variable that affects whether you should spend money on a transport is the extent to which your DAC rejects jitter. If you have a DAC with superb jitter rejection, you can connect a $29 DVD player and be done.

The person who asked the question of McGowan in the video has a Schiit DAC, so, contrary to Mr. McGowan's advice to him that he not spend a lot of money on a transport because of his system's low "resolving power," the Schiit owner may want to check Amir's measurements to see whether the DAC has good jitter rejection. The easiest thing may be to sell the Schiit and get an RME or a Matrix Audio so that he doesn't have to worry about jitter. But of course he won't do that because he's asking Paul McGowan for advice.

Did I mention that I loathe the term "resolving power"?

 

[restorer-john]

So, I’d interpret from the response that a ripped file data stream can be quality checked in a way that is hard to replicate with a real-time CD transport.

This is true, but on the other hand, most discs have errors and the older the disc, the more errors and damage it is likely to have. Does it not make sense to have arguably the best retrieval devices for playing (in real time) discs both now and in the future? If you want to play a disc, nobody wants to be messing around waiting to EAC to exhaust its error correction and give up when you could simply play it on a proper player and be done with it.

Just how long do we think optical drives will be as ubiquitous as they once were and how long will we have people bothering to write software for whatever the latest OS is to extract CD-DA?

Down the track, and probably in less than 10-20 years, the only working machines will be battleship build dedicated CD players to play all those original, uncompressed high quality recordings only available on CD.

When EAC says that there were no errors in ripping a disc, I have never had a problem.

And what do you do with a disc that EAC won't read? Say a disc with a damaged TOC or an EMI deliberately corrupted TOC? Or one that just aborts with errors?

 

[Dialectic]

And what do you do with a disc that EAC won't read? Say a disc with a damaged TOC or an EMI deliberately corrupted TOC? Or one that just aborts with errors?

I pull out an old IDE Plextor drive that I dropped into a USB enclosure. It has read everything I've ever put in it. I use it only when my el cheapo SATA drives can't do the job.

 

[Angsty]

Down the track, and probably in less than 10-20 years, the only working machines will be battleship build dedicated CD players to play all those original, uncompressed high quality recordings only available on CD.

I’m looking at the Cambridge Audio CXC v2 and the Audiolab 6000CDT. Any first hand observations of build and error handling quality? My Cambridge Audio Azur player has worked well for about 15 years without a problem, so I’m inclined to trust Cambridge.

 

[Lao Lu]

Olasonic nanocompo NANO-CD1 CD Transport, Platinum White

4

(21)
World smallest stationary CD transport - Crafted out of seamless, die-cast aluminum, the device measures less than 6" square and 1.5" tall. Designed ...
I was considering that option for a bit and heard good things about this....

 

[Angsty]

Steve Gutenberg really liked this one, but without measurements as a guide, how can you really say it performs better than a $39 DVD player?