Spectrum is a collection of Audio Unit ports of popular eurorack synthesizer modules.

To use Spectrum, load the Audio Units in your DAW or AU host of choice, like Audiobus, GarageBand or AUM. The app itself makes no sound.

Included are:

Spectrum - Multi-mode 8-voice polyphonic oscillator featuring 14 high quality oscillator algorithms

Modal - Modal synthesis. Bowed, Blowed, and Struck sounds through a 64-band resonator. Also included as an effect.

Resonator - 7 beautiful string generation algorithms. Also included as an effect

Granular - Granular sampler, looper, pitch shifter, reverb effect.

Each audiounit also features:
- modulation LFO
- modulation ADSR envelope
- XY touchpad (except on Modal)
- 2-source modulation matrix allowing for complex and evolving patches.
- MIDI CC control of parameters
- Loadable as an AudioUnit effect (except Spectrum)

Spectrum contains DSP code provided under the MIT open source license by Mutable Instruments.

What’s New

Version 0.3

FIXED in 0.3:
- resonator and modal instruments work again in garageband
- added short names
- XY pad modulation from MIDI or AU updates GUI
- MIDI CC list updated
- volume modulation is interpolated, and now works in clouds (for example modulating env -> level)

Ratings and Reviews

5.0 out of 5
51 Ratings

51 Ratings

Joe Salyers ,

Very Cool for Live Performance

I used this bundle this weekend in my live iPad keyboard rig along with AUM and it gave me some very interesting cool sounds that worked perfectly. Great for bending a stretching sounds at the touch of your hand. I hope there will be more of these tools in the future and with iPad OS right around the corner the iPad music community is about to explode with new users and developers. 5 stars!

Mo Freeapps ,

Wow! Outtasite!

This (these) au plug-ins are really cool and I literally had to hand the headphones to my girlfriend to ask her if it sounded like aliens were instructing me through SynthMaster one being played into this. Incredibly dope sound capability. Thanks so much for making it and giving for free.

These plug-ins have made me need to save up for a Modal synth now. Thanks...

spacegeneticsmusic ,


These are incredible creative tools! Brings the limitless potential of a modular approach to iOS. And to offer this for! Thanks for making these creative devices available for iOS music makers! Looking forward to continued experimentation.


Thomas Burns
12 MB

Requires iOS 11.0 or later. Compatible with iPhone, iPad, and iPod touch.



Age Rating
Rated 4+
© 2019 Tom Burns


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