In the early days of PPM I wanted to check out exactly what that thing did. So I made a recording with the left channel pre-encoding and the right channel post-encoding. Then I inverted the phase and lined them up. Once you know what the "chirps" sound like it's possible to detect them on some passages, but even for me - and I'm a pretty critical listener - it's not annoying. I think most of the comments here are about the addition of the Voltair. Yes - that can be annoying.
Dave B.
Dave B.