EFM1 modulation parameters in Logic Pro for iPad
FM synthesis is, at its core, caused by the intensity and type of modulations that take place in the signal path. The modulators outlined in this section have a different impact and role to play than equivalent LFOs and envelopes found in analog synthesizer designs.
LFO parameters
Rate knob: Set the speed of the LFO.
Amount Vib/FM knob: Set the amount of modulation applied to FM intensity or pitch.
If you turn the Amount Vib/FM knob clockwise, you increase the effect of the LFO on Carrier FM Intensity. If you turn the knob counterclockwise, you introduce a vibrato.
If you double-tap to center the knob, the LFO has no effect on FM intensity or pitch.
Mod Envelope parameters
Modulation Envelope sliders: Control both the (Carrier) FM Intensity and Modulator pitch parameters over time. The envelope is triggered every time a MIDI note is received.
Attack slider: Set the time it takes to reach the maximum envelope level.
Decay slider: Set the time it takes to reach the sustain level.
Sustain slider: Set a level that is held until the MIDI note is released.
Release slider: Set the time it takes to reach a level of 0, after the MIDI note has been released.
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