I thought it was pretty easy to deal with noise injection(?)It was 10 years ago, we had relatively low levels of noise to deal with. Today now we have designers making new things, like Class-D, Delta Sigma converters and SMP(S) (sorry Bob), that introduce even more complex noise structures and with much higher output of those noises, now these have to be dealt with as well. Without effecting the core body of the fundamental that we hope should not change "the music and it’s harmonic structure".
Cheers George