I have started seeing isolated spikes in the Nero Disc Quality plots. The C2 spikes are usually about 2000 high. Sometimes they are repeatable, but sometimes a second pass will be clean, or will show a spike in a completely different location, as in the first two figures at:
I see this on discs I burn, and on discs given to me by friends. I see it on cheap blanks, and also on good ones - the examples are from a Taiyo Yuden burned by a friend.
It almost looks like the spikes are in playback, or perhaps it’s just a problem with the NEC 3540A I use for these tests. My Lite-On drive doesn’t show the spikes (see third plot, on same Taiyo Yuden). But the Lite-On is generally much better at error recovery than the NEC, and if I want to simulate what a typical player (car, discman, etc) will see, I try to use the NEC to run these tests.
Are these spikes real, or are they phantoms? I have listened to a few of these, on a boombox or on the NEC, and I don’t hear any problem.
Thanks in advance.