Welcome to Arithmophone.com
The next generation of Arithmophones is on iOS! The first of a new series of touchscreen musical instruments is the Arithmophone Pentatone. The app is completely free (no in‑app purchases, no ads or tracking) and available in the Apple App Store, for iPhones and iPads (iOS 15 or higher).
Download on the App StoreAbout Pentatone
“Beautiful, fun and inspiringly expressive”
The Arithmophone Pentatone is a new iOS music app featuring an easy-to-play pentatonic keyboard and a built-in synthesizer.
Most iOS music apps either give you piano keys or a grid-based interface. Pentatone takes a fresh approach, optimised for the ergonomics of touchscreen devices and inspired by instruments like the kora and mbira. It also features a sophisticated scale selection system that includes all the common pentatonic scale types and unlocks some more unusual ones.
Pentatone features
- Easy-to-play keyboard, split for two-handed playing
- Original pentatonic scale system with 9 selectable scales, in just intonation or standard tuning
- Custom AudioKit-based synth engine (binaural 2×2 operator FM with stereo detune, resonant filter, delay and reverb)
- 25 preset sounds with macro sliders for tone and ambience
- Initial touch and aftertouch response, both polyphonic
User feedback from the Pentatone public beta
“This has such a nice design and ui, colors are fresh and remind me of Piet Mondrian.”
“Sounds incredible and can’t wait to use this in my workflow!”
“This is an inspiringly expressive instrument! Really a joy to interact with.”
“Amazing! Love the simple UI and the musical keyboard. Also the sounds are lovely!”
“It’s very fun to play!”
“Looks beautiful!!!”
Keep an eye out!
Future plans for the Arithmophone on iOS include:
- DIATONE, the diatonic companion to Pentatone, featuring a 7-note-per-octave keyboard with all the familiar major and minor scales and modes
- MIDI / MPE versions of the Pentatone and Diatone apps
- TONEHIVE, a microtonal keyboard synth for 7 limit just intonation
- HUYGENS, a microtonal keyboard synth for 31 EDO
To stay posted, please join the Reddit community or subscribe to the Arithmophone channel on YouTube.
About Arithmophone
An Arithmophone is a thing that turns numbers into sounds, or math into music. Its name is derived from the ancient Greek words ἀριθμός (arithmos; number) and φωνή (phone; sound). Any modern phone or tablet is itself an Arithmophone, because it routinely turns lists of binary numbers into sounds, for example when you use it to listen to music. But the apps in the Arithmophone project are a bit more ‘arithmophonic’ still, because they take pure and simple harmonic ratios like 3:2 and 5:4 and use these to build musical scales. You can use them as musical instruments, as a source of melodic and harmonic inspiration, or as tools for learning about music and exploring the deep connection it has with numbers.