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Does the quality of a digital signal matter?

I recently heard a demonstration where a CD player was played with and without being supported with three Nordost Sort Kones. The difference was audible to me, but did not blow me away.

I was discussing the Sort Kones with a friend of mine that is an electrical engineer and also a musical audio guy. It was his opinion that these items could certain make an improvement in an analogue signal, but shouldn't do anything for a digital signal. He said that as long as the component receiving the digital signal can recognize a 1 or 0 then the signal is successful. It's a pass/fail situation and doesn't rely on levels of quality.

An example that he gave me was that we think nothing of using a cheap CDRW drive to duplicate a CD with no worry about the quality being reduced. If the signal isn't read in full an error is reported so we know that the entire signal has been sent.

I believe he said that it's possible to show that a more expensive digital cable is better than another, but the end product doesn't change.

There was a test done with HDMI cables that tested cables of different prices. The only difference in picture quality was noted when a cable was defective and there was an obvious problem on the display.

I realize that the most use analogue signals, but for those of us that use a receiver for our D/A, does the CD players quality matter? Any thoughts?
mceljo
shadorne's avatar
shadorne
7,333 posts
 
I knew when I posted it,... I would get that answer.... All I can say to you is, have you tried it? I suggest you try it for yourself.

The science is pretty clear on this. If you suffer issues then the difference between the disc material is causing poor D to A conversion. (The machine gets the digital info off the disc but is unable to convert it reliably without audible distortion)

I am not surprised that there were differences - there is a lot of inadequate equipment out there - much of it at the high end. Jitter only became well understood in the mid 90's and it only takes poor isolation of the servo motor driving the CD lens from the clock driving the DAC to get distortion due to jitter. Since the lens servo and motor will be acting in a cyclical pattern (highly likely since it is reading a rotating disc) then these patterns can mess up the sound quality of the CD player - if you replace the disc and it behaves a little differently when rotating then bingo you get a slightly better or worse sound.

The solution is to get a better CD player that will read the data without affecting the quality of D to A.
kijanki's avatar
kijanki
3,575 posts
 
Shadorne - I'm not sure how this interpolation works. Is it happening also when I use program that rips CD as data (like MAX) - I hope not. Do you know?
jea48
2,944 posts
 
The solution is to get a better CD player that will read the data without affecting the quality of D to A.
Shadorne

Shadorne,

I'll let the two dealers as well as other friends, that have heard the difference, they need to get better CDPs.

Best regards,
Jim
mceljo OP
983 posts
 
Jea48 - I currently have the SACD player hooked up in 2 channel analog mode so I'm not even listening to the multi-channel versions. I think most, if not all, SACDs have stereo versions. I don't really care about the multi-channel because my rear channel speakers are no where near the qualility of my Focals.

2 channel standard vs. 2 channel SACD is what I'm comparing. I'm planning to swap the disk and compare the result of standard CDs on both players, but a toslink vs. analog isn't really an equal comparision.
bryoncunningham
888 posts
 
I am a believer in the audibility of jitter. Here is another link to some useful information about jitter. I have also found a lot of useful discussion of this topic in the A'gon archives.

My conversion to believing in the audibility of jitter occurred when I added a reclocker to my system, which discards the timing data from a S/PDIF signal and reclocks it using a high precision clock. The addition of the reclocker resulted in significant improvement in perceived resolution, among other things.
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