Use the ES2 output controls in Logic Pro for iPad
The dynamic stage of a synthesizer defines the level, or perceived volume, of a played note. The change in level over time is controlled by an envelope generator. For more information about envelope generators, see Amplifier envelope.
Envelope 3 is hard wired to the dynamic stage of the ES2—it is always used to control the level of each note. See ES2 envelopes.
The dynamic stage can be modulated by any modulation source in a Mod Matrix slot.

Output parameters
Sine Level slider and field: Set the level of a sine wave signal (at the frequency of oscillator 1) that is mixed directly into the dynamic stage, independent of the filters. See Enhance ES2 sounds with Sine Level.
Volume slider and field: Set the overall instrument output level.
Modulate the ES2 dynamic stage (Amp)
In Logic Pro, set up a modulation routing as follows: modulation target AMP, source LFO1.
Make sure that Via is set to Off.
Adjust LFO settings.
A tremolo effect is created, with the level changing periodically, based on the current LFO 1 Rate value.
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