Mastering.com walks through building modulation from scratch in Logic Pro's Alchemy synth, using a simple saw patch as the test bed.
First up is the LFO, synced to tempo and assigned to filter cutoff, creating a rhythmic sweeping pulse. Depth and rate controls shape how dramatic that movement feels.
Then comes Alchemy's envelope, which uses HDSR instead of standard ADSR, adding a hold stage between attack and decay. Slow attack and hold settings create swelling pads, while short attack with quick decay and release gives you plucky, percussive shapes.
The real payoff is combining both: routing the envelope and LFO to modulate multiple parameters simultaneously. That layering is what separates static patches from sounds that feel alive and evolving.