
Harmonitron
Harmonic tremolo effect
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$2.99
About
Harmonitron is a harmonic tremolo. The rich, swirling amp "vibrato" made famous by early-1960s brownface amplifiers.
A normal tremolo just pulses your volume up and down. A harmonic tremolo goes deeper: it splits your sound into a low band and a high band, then sweeps them in OPPOSITE phase. As the lows swell, the highs dip and back again. That contrary motion is what gives Harmonitron its lush, watery, almost phaser-like character that an ordinary tremolo can't reach.
Turn the Voice control and the effect morphs smoothly from a classic in-phase tremolo all the way to a full harmonic swirl. Drop it on guitars, keys, synths, pads, drums, or a whole mix. Standalone, or as an Audio Unit (AUv3) effect inside GarageBand, AUM, Logic, and other hosts.
THE SOUND
• True harmonic tremolo: anti-phase modulation of a low and high band
• Voice: morph continuously from classic tremolo to full harmonic swirl
• Split & Tilt: place the crossover and balance the two bands
• Tube Drive and tone shaping for warmth and grit
MOVEMENT
• Rate from a slow tide to a fast flutter, shown in BPM
• LFO Shape: sine, triangle, square, and ramp with adjustable edge Slope
• Tempo Sync that locks to your project and lands on the beat, with musical note divisions from 1/1 to 1/32 (dotted and triplet)
• Stereo Spread for auto-pan and rotary-style width
HANDS-ON
• A living hero orb whose two halves breathe in opposite phase — drag it to set Depth, tap to bypass
• Grouped, color-coded controls: Motion, Sync, Harmonic, Stereo, Drive, Output
• Factory presets: Brownface, Rotary Swirl, Slow Tide, Sync Chop, Wide Harmonic and more — plus your own saved presets
PLUGIN & STANDALONE
• Full AUv3 audio-effect support with host presets and parameter automation
• Runs on iPhone, iPad, and Mac
• Standalone mode with a built-in demo pad, live microphone input, or import a song and export the processed result
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What's New in Harmonitron
1.0
July 21, 2026

