Support

Treadle turns your iPhone into a two-axis MIDI expression controller. Drag up and down to send expression (CC 11); glide left and right to add vibrato on a second CC (CC 1 / Mod Wheel).

Getting started

Open the gear icon (top-right) or two-finger tap to reach Settings.
Connect to your instrument: under Bluetooth MIDI, tap “Connect to BLE MIDI device” for a pedal/synth, or “Advertise this iPhone” so a Mac/iPad can connect to it. USB and network MIDI destinations also appear automatically.
Pick a destination, set your CC number and channel, then drag on the screen to play.

FAQ

My instrument isn’t receiving anything.
Make sure a destination is selected in Settings → Output, and that your synth/app is listening on the same MIDI channel and CC number you’ve set.

How do I use it with SWAM / Audio Modeling instruments?
The defaults (CC 11 vertical, CC 1 horizontal) match what SWAM instruments expect for expression and vibrato. Just route Treadle to the same MIDI destination as the SWAM app.

Can I change the range or sensitivity?
Yes — Settings → Range & Sensitivity lets you set min/max values and a response curve for each axis.

Get in touch

Need help or have a feature request? Send a message and we’ll reply by email.