One of the first Moselle patches and still a favorite. 9 detuned sawtooths go through a low-pass and hi-pass filter in parallel, creating a band-pass. The low-pass is 2-pole; hi-pass is 6-pole and has resonance. The resonance is modulated by an LFO, which is modulated by a second LFO, giving it a nice non-cyclical modulation. Half-way through the video, two controls are played with. MIDI General Controller #1 adjusts the curve of the sawtooths from normal to square, by adjusting the Geometric Oscillator's "Power" parameter. Controller #2 just adjusts the detune. That is brought to 0 in the middle of the video, which is when the left/right motion on the oscilloscope stops for a bit.
Note the sound is recorded directly from Moselle: no hardware or external processing was used.