Ah es war der XGain Block, seid 2 Jahren kein VAST und schon geht es los mit den Lücken..
xGAIN dsp multiplies two signal wires together.
When two signals are multiplied, the resulting signal consists of the sums and differences
of the frequencies of each partial of each signal. The frequencies of the original signals
do not come through, unless they have one or more DC components (non-oscillating
partials). And of course, if one of the signals has zero amplitude, the resulting signal also
has zero amplitude.
If the fundamental frequencies of the two input signals are related by simple fractions
(that is, if the ratios between their frequencies are something like 1/1, 2/1, 3/1, 4/1, 1/2,
1/3, 1/4, 2/3, 3/2) the resulting signal will be a harmonic sound. Its partials will be
multiples of one of the original fundamentals, or possibly a new fundamental. If the
frequency ratios of the original signals are nearly but not quite one of these fractions,
some beat frequencies will be perceived, which may or may not be useful. Of course,
with equal temperament, the ratios given above are not perfectly precise (a perfect fifth,
for example, has a frequency ratio of 1.4983, not 3/2). If the frequencies of the original
signals are not at least closely related, the result of xGAIN will be, shall we say, less than
harmonious.
If the frequency of one of the original signals is below the audible range, then the result of
xGAIN is not a matter of harmony, but of amplitude. In this case, a tremolo effect
(amplitude modulation) would be heard, because the resulting signal would periodically
dip below the audible range.