Quick Sampler Mod Matrix pane in Logic Pro for iPad
Quick Sampler LFOs and envelopes are known as modulation generators. These modulation sources are used to control modulation targets, such as oscillator pitch or filter cutoff.
You can assign up to four independent routings of modulation sources and targets in the Mod Matrix pane.
If you’re new to synthesizers and the concepts behind modulation generators, such as LFOs and envelopes, see Intro to synthesizers.
Quick Sampler provides two LFOs and dedicated Pitch, Filter, and Amplitude envelopes that can also be assigned as modulation sources or targets in the Mod Matrix pane.
Your keyboard modulation wheel, aftertouch, pitch bend, velocity, and MIDI continuous controller features can also be assigned as real-time control sources for Quick Sampler parameters in the Mod Matrix.

Mod Matrix parameters
Source pop-up menu: Choose a modulation source.
Depth field: Drag vertically to set the maximum value or intensity of modulation. You can also tap the field to enter a numerical value.
Target pop-up menu: Choose a modulation target.
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