Version OS 1.0
7.4 FM Synth
The FM Synth is a little 4 operators 6-voice digital synth dedicated to percussive sounds.
A versatile FM modulation matrix lets you create almost any of the known FM
algorithms as the 4x4 matrix offers every possible forward and feedback modulation.
7.4.1 FM Synth modulation matrix
If you select the FM synth track on page A, the 4x4 knob matrix resembles the following
scheme:
Each knob of the green diagonal is one operator and the knobs OP1-OP4 control the
base frequency of that operator.
The knobs in the upper half of the matrix control the amount of FM modulation
according to the direction of arrows. The horizontal arrows indicate the direction of
output of the operators. The vertical arrows indicate the direction of modulation (FM1-
FM4). The index of the FM modulation describes the destination of that column (for
instance, all FM4 modulate OP4). That means the upper half is the forward modulation.
OP1 modulates OP2, OP3 or OP4 according to the amounts set by the blue FM knobs in
the first row. OP2 can modulate OP3 or OP4 in the second row and so forth.
The lower part of the matrix is the feedback modulation, indicated by the arrows going
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ALPHA BASE Operating Manual
OP1
FM2
OP2
OP3
FM3
FM4
FM3
FM4
FM4
FM1
FM1
FM2
OP4
FM3
FM1
FM2
