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
If redbook manufacture is supposed to commence play at exactly 2.00 seconds from the true zero pressed on the cd aren't we discussing data here.Programs like the forgotten Perfect Rip take this very seriously,correcting for sub-channel data in the process etc.Bit correction for offsets is what it is all about.I have discovered that Nero CD Speed Tool does report offsets correctly,just giving a total figure.Perfect Rip confirms Nero and this means that the Accurate Rip database is incorrect.All offsets given there are +30 samples out for every drive listed.I no longer get silly anamolies with ripping,they are perfect every time.I might add that voltage brown-outs and spikes badly effect ripping also.You reap what you sow.
Kijanki,
The Reed Solomon interleave is actually quite robust however CD players will indeed "interpolate" as a last resort when data is missing

It is true that you might not know when your CD player is interpolating unless the disc is quite badly damaged and you get pops or clicks. Normally you should be well aware of errors when music is copied with a PC with good software (sometimes you need to set the software to warn you about read errors).

I have had some CD's that suffered CD rot - they played on a CD player but could not be copied without error on a PC - to me this means that they are beyond repair and the data cannot be recovered - but this problem is possible with any digital format that gets really badly corrupted or damaged. Under normal use with good quality discs one should not normally run into problems.
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.
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?
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