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The Doppler

DesktopDigitalPolyphonic

Picture this: a pint-sized desktop FM synth that packs an 8-voice polyphonic punch into a stompbox-sized chassis, making classic FM tones feel fresh and endlessly tweakable with every knob turn.

At its heart is a streamlined 2-operator engine where a sine wave modulator—tuned precisely via stepped octave and semitone switches—can hit the carrier's frequency, phase, or both, plus a feedback loop and pink noise for extra grit. Toggle phase or frequency mod on or off, crossfade between carrier and modulator, shape with a 4-pole lowpass filter, and twist a versatile ADSR envelope that defaults to the carrier but can also control FM depth via Env Mod switch, while Mod Trail adds a swelling attack just to the modulator. Built-in stereo delay with tap-tempo touchpad and lush reverb (with expanded controls over its sibling synth) let you process its sounds or external stereo audio through TRS ins and outs; plug in via USB-C MIDI host for controllers, DIN MIDI in/out, and power it all from USB-C.

Since launching post-Kickstarter in 2023, it's earned praise for hands-on immediacy and surprising depth from cold bells to immersive pads, though some find the stepped modulator tuning a quirky constraint rather than a smooth glide.

Released

2023

Status

In Production

Synthesizer
Format
Desktop
Type
FM, Digital
Internal Battery
No
Voice
A/D
Digital
Polyphony
Polyphonic
Oscillators
0
Oscillator Type
FM Operators
Voices
8
Filter
Yes
Envelopes
1
LFO
0
Effects
delay, reverb
Expression
Aftertouch
No
Velocity
Yes
MPE
No
Additional
-
Software
-
I/O
Audio In
1
Audio Out
1
Headphone
0
MIDI
In, Out
MIDI Type
DIN (5-pin), USB
Ports
USB-C
Wi-Fi
No
Workflow
Arpeggiator
No
Sequencer
No
Mod Matrix
No
Memory
No
Measurements
Dimensions
-
Weight
-
Last updated Feb 25, 2026