Pentatone

Arithmophonic keyboard synthesizer

"Beautiful, fun and inspiringly expressive" - The Arithmophone Pentatone is a music app featuring an easy to play pentatonic keyboard and a built-in synthesizer. Instead of using 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. The app also has a sophisticated scale selection system that includes all the common pentatonic scale types and unlocks some more unusual ones.

Pentatone features:

• An easy-to-play keyboard, split for two handed playing
• An original pentatonic scale system with 9 selectable scales, in just intonation or standard tuning
• A custom Audiokit-based synth engine (binaural 2x2 op 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: "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, my friend! 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!!!"

Pentatone is part of the Arithmophone project An Arithmophone is a thing that turns numbers into sounds, or math into music. Its name is derived from the ancient Greek words arithmos (number) and phone (sound). Any iPhone or iPad 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 this app is a bit more 'arithmophonic' still, because it takes pure and simple harmonic ratios like 3:2 and 5:4 and uses these to build musical scales. You can use it as an easy-to-play instrument, a source of melodic and harmonic inspiration or a tool for learning about music and exploring the deep connection it has with numbers.

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 Pentatone and Diatone
• TONEHIVE, a microtonal keyboard synth for 7 limit just intonation
• HUYGENS, a microtonal keyboard synth for 31 EDO

To stay posted, join the community at reddit.com/r/arithmophone or subscribe to the Arithmophone youtube channel: https://www.youtube.com/@arithmophone