Subtractive synthesis, envelopes, FM
This video shows how to create an instrument, first by creating a dot with harmonics, editing the intensity of the harmonics using Horizontal Curves/Average, then how to apply an envelope to that basic tone by drawing a curve on a new layer and turning it into a suitable multiplication layer using Fill from Maxima to Bottom and Vertical Average, and then how to apply some frequency modulation to make the pitch shift up and down by drawing a sine-like curve and using Vertical Propagation.
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