Manual

Synthesizer Voice A-111-5 System A-100 DOEPFER
16
14a LFO1 Frequency
14b LFO1 Frequency Range Switch
14c LFO1 Waveform Switch
This group of elements is responsible for the adjustment of
Low Frequency Oscillator 1 (LFO1).
Switch 13a is used to select the frequency range:
upper position: low ~ 0.005Hz/200s ... 2.5Hz/400ms
center position: high ~ 20Hz ... 10kHz
lower position: medium ~ 0.1Hz/10s ... 50Hz/20ms
The lower position is the standard LFO setting. The center
position is mainly for FM/PWM/AM effects in the audio
range. The upper position is for very slow modulations up to
several minutes range. As the frequency ranges overlap
some frequencies can be generated in two ways (e.g. 1Hz is
covered by low and medium range).
The frequency is manually adjusted by control 14a LFO1
Frequency.
The waveform switch 14c is used to select the waveform:
upper position: triangle
center position: no wave
lower position: rectangle
The LED next to the control 14a displays the present
frequency and waveform. Positive shares of the signal are
indicated by green (or yellow) color, negative shares are
red. The brightness of the LED corresponds to the voltage
level (bright green means high positive voltage, dark red
means small negative voltage). If rectangle is selected the
LED switches between full green and full red as the
rectangle has no slope.
Remark
: If the LFO frequency goes above about 25 Hz, our
persistence of vision means that the LED looks permanently
on. Consequently only frequencies up to ~ 25Hz can be
recognized. If both the green and red light source of the
LED are "on" a frequency beyond ~ 25Hz is adjusted.
15a LFO2 Frequency
15b LFO2 Frequency Range Switch
15c LFO2 Waveform Switch
This group of elements is responsible for the adjustment of
Low Frequency Oscillator 2 (LFO2). The functions of the
controls and the LED are the same as for LFO1.