Bit Perfect ZP90

.The main reason (initially) was it gave bit perfect sound and I found it is easily better than CD provided you rip with EAC.

If I buy a second hand ZP90 is it guaranteed to be bit perfect?
How can a conversion, even a lossless one, be even slightly better than the original?
Based on all reports here, there has been no change made to zp90s, so, for what its worth, it will be bit perfect.

Thanks for the reply. The sonos faithfully reproduces the data extracted from the disc provided it's accurate. My CD player was not great and the zp90 is a massive improvement.

How can a conversion, even a lossless one, be even slightly better than the original?
A CD player must read the data in real-time. Built-in forward error correction will allow some recovery of mis-read data, but it can only go so far.

A rip, especially one by a secure ripper such as EAC, can take as long as it wants to ensure the data is read accurately. This can include multiple passes and, at the end, a comparison of the track's checksum with online databases.

My question was with reference to the CD, not the output from the CD player because the first OP post wasn't clear which of the two was being referred. Even with a CDP though, how would the errors/misreading manifest themselves? A stutter here or there, or an overall SQ degradation? I suspect the former; if so, if one doesn't hear these stutters, all is good?

I believe that a CDP which is unable to recover lost bits using forward error correction (in essence, redundant data) will 'make up' the missing samples, either by interpolation or simple repetition.

Yes, but how will this get manifested in what is heard?
Something I came across recently - Reed Solomon coding invented over 50 years ago and used in CDPs from the beginning. Quote: This code is so strong that most CD playback errors are almost certainly caused by tracking errors that cause the laser to jump track, not by uncorrectable error bursts.[5] Unquote
Relevant to topic?

Although the OP has heard what he wanted to - I think - an interesting question nevertheless. If I was to take a standard CDP from the early days, that is in good working condition, and one bought today off the shelf and not an exotic high end version, and played a recent high recording quality CD via both, would I hear any differences, assuming no other variables?

Presumably as tiny degradations in audio quality, though by the sound of things tracking errors are more common. All I can say is that I've seen EAC make multiple attempts to read the data before succeeding. A CDP doesn't have that luxury.

Yes, and I strongly suspect that the tiny degradations would be lost downstream in the chain before the sound hits the ears. When I rip CDs in iTunes, I do check the error correction box of course; other than a little more ripping time, there is nothing to be lost in doing that.

And although technically obsolete now, I also suspect that the GBP 50 kind of DVD players that also play CDs are perfectly adequate if one must still play CDs.

Yes, and I strongly suspect that the tiny degradations would be lost downstream in the chain before the sound hits the ears. When I rip CDs in iTunes, I do check the error correction box of course; other than a little more ripping time, there is nothing to be lost in doing that.

And although technically obsolete now, I also suspect that the GBP 50 kind of DVD players that also play CDs are perfectly adequate if one must still play CDs.

You rip in iTunes? You surprise me. The amount of times accurip reports problems, especially with end tracks in a disc, I wouldn't use anything but EAC with that plug in.