M2DX
MIDI 2.0 FM Synthesizer
Only for iPhone
Free · Designed for iPhone. Not verified for macOS.
iPhone
M2DX is a 6-operator, 32-algorithm FM synthesizer for iPhone, built from the ground up in pure Swift 6. Open it and play immediately — tap the built-in on-screen keyboard and start making sound with M2DX's own hand-crafted presets. No external hardware or MIDI controller is required.
The FM engine is a bit-exact port of the open-source Dexed / msfa DSP, verified sample-for-sample against the reference. It is also compatible with the classic DX7 patch format: bring your own DX7-format .syx banks and play them alongside M2DX's originals.
KEY FEATURES
- Built-in on-screen keyboard with velocity and octave control — play standalone, no hardware needed
- 6-operator, 32-algorithm DX7-style FM synthesis
- M2DX's own original FM presets, plus DX7-format .syx bank import (bring your own)
- A 6-stage FX chain: EQ, Drive, Chorus, Reverb, Stereo, Maximizer
- Low-latency audio with AVAudioSourceNode direct rendering
- AUv3 plug-in — use M2DX as an Audio Unit (AUv3) in compatible hosts
OPTIONAL MIDI (not required to use the app)
- Connect any MIDI controller over Bluetooth or USB if you have one
- Native MIDI 2.0 — UMP with 16-bit velocity and 32-bit controllers
- MIDI-CI Property Exchange — patch names appear on compatible controllers (for example, KORG KeyStage)
- MIDI Learn for hands-on control
MIDI 2.0 done natively, classic FM done faithfully.
The FM engine is built on Dexed / msfa (Apache License 2.0).
M2DX is an independent product and is not affiliated with, endorsed by, or sponsored by Yamaha Corporation. DX7 and Yamaha are trademarks of Yamaha Corporation.
iOS 18 or later.
Ratings & Reviews
- This app has not received enough ratings or reviews to display an overview.
• Fixed: a preset's sound could subtly change just from opening Operator pages — viewing operators no longer alters the voice.
• Fixed: editor presets could sound thin in some AUv3 hosts.
• Fixed: a rare crash and stability issues around the on-screen keyboard and AUv3 hosting.
• Improved: Operator Ratio now snaps to the classic FM ratios (1.00, 2.00, 3.00...), making precise FM programming much easier.
• Various reliability improvements.
Thanks to everyone sending feedback — keep it coming!
The developer, Hakaru Hirose, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Provider
- Hakaru Hirose
- Size
- 11.7 MB
- Category
- Music
- Compatibility
Requires iOS 18.0 or later.
- iPhone
Requires iOS 18.0 or later. - Mac
Requires macOS 15.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 2.0 or later.
- iPhone
- Languages
- English
- Age Rating
4+
- 4+
- Copyright
- © 2026 Hakaru Hirose