Rithmatic

Best Practice Chicago

In-app purchases

About this app

Rithmatic makes the legendary sound of FM synthesis something you can finally browse — over 36,000 classic DX7 voices, each one a tap away from playing, and not one of them needs any hardware to hear.

It is a companion for your FM hardware, too — from a vintage Yamaha DX7 to a Korg volca FM2.

HEAR EVERYTHING — no hardware required
• Over 36,000 unique FM patches, gathered from the great DX7 banks and de-duplicated down to the ones that genuinely sound different — Yamaha's factory ROM, the "DX7 All The Web" archive, and hundreds of packs besides.
• Tap any patch and it plays at once, rendered right on your device by a built-in FM engine based on the open-source MSFA synthesis core. Nothing to connect, nothing to download.
• Play a patch from the on-screen keyboard or any MIDI controller.
• Browse the way your ear does. A Character axis sorts every voice — Bright, Metallic, Plucked, Swell, Evolving, Mellow and more — alongside the categories you'd expect: Pianos & Keys, Synths & Leads, Brass & Winds, Strings, Bass, Bells & Mallets, Pads and Organs. Search by name and star your favorites.

BUILD YOUR OWN
• A six-operator patch builder that puts the whole voice on one screen — carriers and modulators, routing, feedback and a waveform per operator, across all 32 FM algorithms.
• Audition as you build, through the app, your synth, or both at once.

PLAYS YOUR FM HARDWARE
• Send any patch straight to a real DX7-family synth over MIDI — a Yamaha DX7, TX7 or TX802, a DX7II, or a Korg volca FM / volca FM2 — and play it from the on-screen keys or a controller.
• It reads back, too: when a synth transmits a voice or a full bank, Rithmatic imports it into your library, named and filed with the rest.
• The Korg volca FM2 gets the deepest link — two-way patch editing, all 16 of its sequences, and full-instrument snapshots you can capture and restore.
• Choose your instrument in Settings: a DX7-family synth connects one way (send and listen); the FM2 talks both ways.

Rithmatic is local-first: it works offline and keeps your library on your device. No account, no ads, no tracking. The app is free — and if it earns a place in your setup, a one-tap tip in the Support tab goes straight into the next release. Tips are handled by the App Store or Google Play; Rithmatic never sees your card.

WHAT NEEDS THE HARDWARE
The patch library, playing and auditioning, and the patch builder all work entirely on their own. Sending patches to a synth and receiving them back need that synth connected over MIDI — on a phone or tablet, through a USB or Bluetooth MIDI adapter. Editing patterns and capturing full-instrument snapshots need a Korg volca FM2 specifically.

DX7 and Yamaha are trademarks of Yamaha Corporation. KORG and volca are trademarks of Korg Inc. Rithmatic is an independent app and is not affiliated with, sponsored by, or endorsed by Yamaha or Korg; those names are used only to describe the hardware and patch formats the app works with.

What’s new

Bug fixes and performance improvements