obsession: frequency shifter side band rejection

[Martin Czech]

For all the obsessed of you:

Ok, after all this discussion I understand that side band rejection is not
so important for low shift values (<10Hz or so).  If we modulate with a
simple multiplier, the two sidebands are equally strong and this leads to
the sensation of amplitude variation (beating). Therefore a frequency
shifter is used. In order to avoid this -40dB side band rejection is
sure enough, the ear doesn't notice the beating then (I hope so).

OTOH, if one trys to give voices or melodies a larger shift (say 100
Hz or 400 Hz), the unwanted side band will not sound like beating,
but like some strange background noise. For this application it would
be desireable to have the highest side band rejection  that is possible.

These two applications are different, this confused me a lot.

m.c.