Prompt Audio · Lead synth
Kestrel
A four-layer lead synth where every knob holds two settings and morphs between them
Kestrel stacks four complete synth layers in one program, each with two oscillators, a filter and its own effects. Every knob stores a second setting, and velocity or the mod wheel morphs between the two. It comes with 5,120 factory programs in 40 banks, all level-calibrated.
- Programs
- 5,120
- Layers
- 4
- Voices
- 32
- Filter types
- 8
What it does
Four layers from one pool of 32 voices
Each layer is a complete voice with its own effects. MIDI channels 1 to 4 play layers A to D, and channel 5 plays every active layer.
A second setting behind every knob
Each knob has a morph state. Velocity, the mod wheel or both move the sound from the first setting to the second.
Two oscillators per layer at 2x oversampling
Both oscillators are band-limited and offer FM, ring modulation and hard sync. Eight zero-delay-feedback filter types include a formant filter and an 8-stage phaser filter.
Effects and a gate sequencer on every layer
Chorus/phaser, a pan LFO, a cross-feedback stereo delay, a 1 to 32 step gate sequencer and a limiter. 8 gate patterns and 6 delay rhythms load as presets.
Arpeggiator, unison and 48-semitone bend
The arpeggiator has 5 modes over 1 to 5 octaves, free-running or tempo-synced. Unison plays 2 voices per key in poly and 4 in mono or legato.
SysEx in and out
Kestrel imports and exports SysEx patches, bank dumps and performance dumps. The standalone app follows MIDI clock.
Good to know
- All four layers draw from one shared pool of 32 voices.
- Unison is limited to 2 voices per key in poly mode.
System requirements
- macOS 11 or later
- Apple silicon or Intel Mac
- Formats: AU, VST3, Standalone
- A host that loads Audio Units or VST3 plug-ins, for the plug-in versions
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