First off many thanks for Steve N. for sending me the Jitter-free copy of Norah Jones.
First off I made my own copy of the CD and did a quick comparison between the three CDs and there were some interesting results.
1) Steve's copy is 45:35 the original and my copy are both 45:09 , Steve's copy has 2 seconds padding on all but the last track, Nero which I used makes a bit-copy.
2) I tested all CDs using
EAC test DA extract
Nero CD Speed
Nero DAE test utility
Both copies (mine and Steve's) read noticeably slower than the Commercial CD sometimes my copy was marginally faster than Steve's , sometimes it was slower but there was precious little in it
EAC extracted tracks from all CDs with no reported errors and the peak levels on all versions were the same for all tracks. Steve's copy showed 99.8% on 4 tracks and 100% on the rest, the original and my copy both showed 99.8% on 3 tracks (the same tracks) but in my experience this is EAC being paranoid and 99.8% does not mean audible errors. There is nothing here to suggest that the CDs are really any different.
Nero DAE shows all CDS will extract with zero errors.
So as far as the Computer is concerned the CDs are functionally identical nothwithstanding some minor differences.
I have been doing listening tests on the original and Steve's copy.
I have done sighted two transport tests with switching but that does introduce another variable and although I could not discern any difference it would not be fair to use that example as the differences between the transports could mask a difference. In any case synching is a problem as the copy has 2 second padding and so it has to be resynched after each track
I have also set up a random play program with the same track (Track 10 - Painter Song) on the two CDS playing in a changer without me knowing which is which. This does introduce a slight time lag between tracks about 10 seconds. I had an indepdendent person (the missus) load the CDs without telling me which was in which slot and the player does not do CD text so there are no clues as to which is which. There is no difference in mechanical noise, actually in play the player is dead silent. I have kept the volume the same throughout the exercise.
I have been listening to the two versions continuously and between toast breaks for a couple of hours. Sometimes the whole tracks sometimes sections of the tracks.
I cannot discern any difference between the commercial CD and the jitter-reduced copy, in my system with my ears and so forth, hardly conclusive I know but that is my data point.
It was fun trying though and I hope I did approach the challenge with an open mind and and open ears.
One unfortunate side effect is that I quite like Norah Jones now - it is like I have been bludgeoned into submission.
Thanks for the Classical sampler - will give it a play now.
Edit: Tannhauser overture is up first - thanks - one of my favourite pieces - a somewhat languid offering - who is doing it ?
Coincidentally I was just thinking I must put some Wagner on to be an antidote to Norah Jones...