Doepfer A-137-1 Wave Multiplier - Manual

doepfer System A - 100 Waveform Multiplier A-137
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1. Introduction Module A-137 is a Voltage Controlled Waveform Mul-
tiplier. The basic idea of a wave multiplier is to multiply
the waveform of an incoming signal (e.g. triangle from
a VCO) within one period. This leads to additional
harmonics. The period and consequently the pitch of
the signals remains unchanged - in contrast to fre-
quency multiplication e.g. with the PLL module A-196.
The A-137 works as a kind of "inverse low pass filter",
i.e. it adds a lot of harmonics to the incoming signal.
Consequently the best results are obtained with signals
that contain none or only a few harmonics (e.g. triangle
or sine waveforms). The A-137 can be used with signals
rich in harmonics too (e.g. saw) but the effect is not as
remarkable as for triangle or sine waves.
The A-137 is a very sophisticated wave multiplier that
offers much more features, more controls and more
waveform manipulations than other wave multipliers
available so far. In addition all four parameters are both
manually adjusted and controlled by external volta-
ges:
• Multiples: number of waveform multiplications
• Harmonics: adds more harmonics similar to the re-
sonance/emphasis control of filters
• Folding Level/Symmetry: value and symmetry of
the upper/lower folding level