Not a great question mate i ahve to say. What aspect of modulation filter envelope, pitch, index, volume its an endless list.

To modulate a sound you must have a control voltage or an LFO routed to whatever sound you wish to modulate. For example reasons malstrom had modulation sections on the top of the synth. try turning the pitch one left or right and there you have it a modulated sound. then you have speeed of modulation depth etc this can be applied to any aspect of a sound.

Be specific and I will try to help best I can

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Processing a highly structured and complex pattern of sensory input as a unified percept of "music" is probably one of the most elaborate features of the human brain.....understanding how music is perceived and how it may elicit intense sensations is far from being understood.