Kirnu Interactive ButterSynth for iOS AUv3 takes you on a 6-OSC multi-voice synth journey with wavetable, FM, granular and rich modulations.
UPDATE: ButterSynth is available now for $19,99. Join the Synth Anatomy Patreon page in April to win 1 of 3 codes.
After a slump in late 2021/early 2022, the iOS market has been really taking off for a few months. Many new developers have joined, including names familiar to the desktop market, such as AudioThing and Unfiltered Audio. Many of these plugins are now also available for AUv3 on iOS. More such ports are very welcome.
Kirnu Interactive has also done this with its MIDI arpeggiator/sequencer Cream. The developer has been working on a new app called ButterSynth for a long time. A new powerful Synthesizer app that many are eagerly awaiting. The release is now known set for April 28th, 2023.
Kirn Interactive ButterSynth
ButterSynth is a new multi-voice synthesizer for iOS with AUv3 plugin support. Multi-voice because the synth has multiple synthesis engines in one. It has 6 oscillators consisting of two wavetable oscillators, a sampler, a 4-OP FM, and a granular sampler. These can be mixed together at will.
The individual engines are anything but lightweight. They are feature packed and on par with desktop synth plugins. The dual-wavetable synth engine features hundreds of built-in wavetables, 9 phase modes, wave folding, and hardware-modeled rich unison Plus, you can work with a wavetable editor, allowing you to tweak, morph, and hand-draw your own custom wavetables (up to 256 frames).
Both the sample and granular sampler engine let you load the factory or custom samples and control precisely the chopping, triggering, and layering process. It also includes the same unison modes as the WT engine. The whole thing is also visualized so that you can work more precisely with the sound content.
The fourth and last engine is the FM synth offering four operators with a selection of 12 preset modulation paths. And you can’t do FM only with sine.
ButterSynth’s operators in the FM engine support any waveform from the factory or user library. Plus, you can also self-modulate via the feedback dial. So you have four synths in a single app.
Flexible And Powerful Routing
Not only are the oscillators flexible, but also the complete routing system. Thanks to touchable dots, the user can determine which elements are routed to one another or also routed into. For example, there are two great-sounding multi-type filters with classic cutoff, resonance, drive, and volume controls.
Per oscillator can decide whether it goes through the filter, two filters, or not at all. Then, you can also activate the modulation per oscillator. The modulation engine is pretty hefty: four ADSR envelopes, four MSEG-style looping curve envelopes, four multi-wave LFOs, 4x customizable step sequencers, an X/Y pad with motion recording, a powerful Cream-inspired arpeggiator, and eight macro dials.
These are powered by a highly-configurable 32-slot modulation matrix with precise mix/max ranges, self-modulation, configurable response curves, and layer modes. Any other wishes? Okay, I would like to have a bit more random modulators but you can always wish for that later in an update.
Multi-FX
Further, you can refine your sounds with a complete multi-fx processor, consisting of 16 built-in FX modules: three more filters, delay, reverb, distortion, crusher, chorus, OTT-inspired compressor, and more. The FX are also modulable and thus you can achieve very complex sounds.
Kirnu Interactive ships ButterSynth with AUv3 support for iOS, meaning you can use the synth in multiple instances. It is not yet known whether the AUv3 will be extended to macOS. I would be an awesome next step.
First Impression
ButterSynth has been in public beta for a long time. I also benefited from this opportunity and took a close look at the synth. In my opinion, ButterSynth is one of the synth highlights of this year, if not the best release. It’s hard to top what Kirnu Interactive aka Arto Vaarala has squeezed into the synth here.
The feature set is huge, but don’t worry. The synth itself is very intuitive to use thanks to its well-designed and structured user interface. The quality of the engine is on a very high level and offers almost unlimited sound possibilities thanks to its multi-voice architecture. Do you want a high-quality synth for iOS at the level of desktop plugins? Here you get it.
Kirnu Interactive ButterSynth is available now on the AppStore for $19,99 USD for iPad with AUv3 support. According to the developer, an iPhone and macOS AUv3 will follow soon.
More information here: AppStore
Hi Tom, hope you got a few more Patreon subscribers!
If you still have or are getting more codes, let us know. 😊