Arturia Forums
Hardware Instruments => PolyBrute => PolyBrute - Feature requests => Topic started by: Michael_G on January 06, 2022, 07:59:21 pm
-
I'd be very happy to have the ability to change/moduate dynamically the LFO pulse width (VCO like actually) or at least to have a choice of different fixed pulse widths in the settings menu.
It becomes really helpful when modulating an output level (eg. VCO or filter) to create a periodical FX.
-
Although not a "full" solution, you can use both LFO 1 and 2 together to get a variable pulsewidth LFO, using the saw + inverted saw trick:
- set LFO 1 to saw and LFO 2 to inverted saw
- set LFO 1 and LFO 2 to Retrig mode
- set LFO 1 and LFO 2 to Sync on
- set LFO 1 and LFO 2 to the same clock division
- assign both LFOs with the same amount to your destination in the mod matrix
Now you can use the Phase control for LFO 1 to set the duty cycle between 0% and 50%. The absolute output of the combined LFO varies with the pulse Phase setting, so if you modulate Phase to get PWM the output level will change too. The drawback is that since the LFOs are Synced, you must use the Sequencer rate and LFO divisions to get the rate you want.
You can also have both LFO 1 and 2 set to the same waveform, saw or inverted saw, and then use opposite polarity for their mod amounts, in case other simultaneous uses of the LFOs would benefit from from that.
Finally, LFO 3 can almost get an adjustable PW using the v 2.0 feature of inverted rise segment. That's "almost" as in there will be a slightly bendy curve on the rise and fall portions, not a fully square waveform. The advantage is that the output level is constant for all PW settings. Hold the Settings and twist the Curve knob to get the rise curve menu and select Inverted, then set the Curve knob to the max or min value. Now you can set or modulate the PW with the Symmetry knob.
Depending on the application, the slight curve on the rise and fall segments when using LFO 3 could be anything from acceptable to cool. The Curve knob can be used to set the amount of curving, with the extreme curves in its middle position, and the straightest edges at its max or min settings.