Bastl PIZZA - FM; FM INDEX fader; INDEX MOD knob and FM INDEX CV; OCT OSC button

2 – FM INDEX fader
FM INDEX is the depth of frequency modulation (phase modulation, in
fact) applied to the MAIN oscillator (carrier). In the middle position, no
modulation is applied, and when no other waveshaping is applied, you
should hear asine-wave at the MAIN output.
When moving FM INDEX to the left, the RATIO oscillator modulation is
applied.
When moving FM INDEX to the right, the OCT oscillator is applied as the
modulator.
3 – INDEX MOD knob and FM INDEX CV (-6V to +6V)
The INDEX MOD knob is an attenuverter that will control how much of
the CV applied to FM INDEX CV input affects the FM INDEX. Turning
the knob to the right will apply the modulation in apositive sense (as if
moving the FM INDEX fader to the right). Turning the knob to the left will
apply the inverted modulation (as if pushing the FM INDEX fader to the
left).
4 – OCT OSC button
Press the OCT OSC button to select one of 4 octaves for the octave
oscillator. The lights indicate the active setting.
5 – RATIO OSC button
Press the RATIO OSC button to select one of 4 user-settable frequency
ratios for the RATIO oscillator. The frequency ratios can be adjusted in
the RATIO SETTING mode.
RATIO SETTING mode:
Long-press the RATIO OSC button to enter the RATIO SETTING mode.
Select the ratio to be edited by clicking the RATIO OSC button.
Most musical intervals can be defined as simple ratios between
frequencies. Perfect fifth has aratio of 3/2 to the root note, major third
has aratio of 5/4, and so on.
Use the PITCH knob and PITCH button to set the frequency ratio.
There are 2 components to the ratio A/B: A=numerator and B=denominator.
When the OCTAVE light is on, you can set the numerator of the current
ratio with the PITCH knob (range 1-16). When the DETUNE light is on,
you can set the denominator of the current ratio with the PITCH knob
FM