Additive Synth

WHAT IT IS

Additive is a synthesizer that builds each sound up from harmonics instead of using a filter to cut it down. You can set every harmonic individually, then shape how it moves over time: some can pulse together while others drift, shimmer, or move in the opposite direction. This gives you control over every part of the spectrum and a large range of sounds, from shimmering pads and bell-like plucks to deep resonant basses. Start with a preset, generate a sound with Random, or build your own from the ground up.

WHAT IT DOES

* Harmonic bank: set up to 50 harmonic bands by drawing them, picking a shape, or generating a random spectrum. Every band is yours to change.
* Custom movement for every harmonic: give each band its own modulation depth, phase, and rate, so the movement happens inside the sound.
* Cutoff and resonance, uncoupled: Bands and Slope set the cutoff, while Bulk is a resonant peak you can place anywhere in the spectrum, independent of where cutoff sits.
* Morph: draw two spectra and move between them by hand, with an LFO, or with an envelope. A note can begin as one sound and become another.
* Modulation: four LFOs with nine shapes, including ones you can draw yourself, plus tempo sync and four envelopes.
* Voicing: Character, Detune, Chorus, Drive, and Stereo take the harmonics from pure sine waves to analog-leaning, distorted, or otherworldly.
* Play the spectrum: assign brightness, movement, Morph, or anything else to the XY pad and the Z slider, and explore the movement inside the spectrum yourself.
* Presets and Random: more than 100 presets cover basses, pads, textures, plucks, leads, bells, organs, keys, brass, and drones. Random generates a whole new sound, and you can adjust every detail to make it your own.
* FX: delay, reverb, drive, compression, and EQ are built in, so your sounds leave Additive finished.
* AUv3 and standalone: load Additive as an instrument in your host, or play it directly in the app with the on-screen keyboard and arp.
* Four themes: Hardware, Cobalt, Dark, and Light.

REQUIREMENTS

* iPad with iPadOS 15 or later
* An AUv3 host for the plugin, for example AUM (the standalone app needs none)