Bassline or melody generator from Serge VCFQ

In this video I describe how to make a melody generator from a pingable low-frequency filter. I use the Serge variable Q filter (VCFQ). First I divide a clock source by the number of pulses that I want in the melody. Here is is 8 steps. I use the TKB sequencer to do this division, taking the pulse reset output from step 9 to ping the filter. However, the clock division could be done with the Serge Divide-by-N COM, Serge USG, or any clock divider. The output of the divider goes to the TRIG input of the VCFQ, to ping it, causing a resonant excursion at a very low (sub-audio) frequency. The output of the filter (BAND HIGH, LOW or with a smaller ambitus, NOTCH), goes to the IN of the SSG Stepped Generator. The STEPPED OUT of the SSG goes to the attenuverter (variable control voltage) input of the New Timbral Oscillator, to control the frequency in steps. The STEPPED OUT can be taken via a quantizer, but since the output is bipolar, the voltage needs to be raise to a positive level before going into the quantizer. I use one side of a Dual Processor to do this, with a few volts of positive bias. The two knobs that control the character of the melody are the filter Q (resonance) and the filter FREQUENCY. The polarity of the excursion can be controlled at the attenuverter, or at the Dual Processor. All the filter outputs produce voltage excursions simultaneously, with different characters to the pattern. The melody always synchronizes to the ping, so if the FREQ and Q settings are left to settle, a steady pattern will result. One addition I didn’t show in the video is that the different filter outputs (BAND, LOW, HIGH, NOTCH) can be used to modulate a filter, or other effect, or the variable waveform of the oscillator. Incidentally, this is only one of many ways the low-frequency filter can be used as a control voltage source or modifier. Enjoy!