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Töörö Editor

Cross-platform sound editor for the Fred's Lab Töörö hardware synthesizer. This application was developed in close cooperation with the manufacturer.


The application is written in Rust and features the Iced GUI library and the midir crate for MIDI processing.


The editor currently supports:

  • Editing of most preset and multi parameters
  • Loading and saving of presets as sysex files

Being an open source project, user contributions to the code are always welcome.


Using the editor is mostly self-explanatory, but there are a few things to be noted:

  • The Töörö must be connected to the computer via USB. DIN MIDI will not work.
  • When using a DAW at the same time as the editor, make sure it does not loopback sysex messages to the Töörö.
  • You can select a MIDI input for playing the Töörö while editing via the Merge Input dropdown list on the bottom of the application window.
  • Silders can be fine-controlled by holding the SHIFT key while dragging.
  • To reset a slider value to it's default, use CTRL-click or right-click.
  • The mouse wheel can also be used to change a slider value.
  • The Töörö firmware must be V1.5 or higher. Otherwise, not all parameters can be edited.
  • The application tries to detect when you change a parameter on the device itself. Unfortunately, this will not work in all cases. Use the Update from device button to force a reload of all parameters.
  • A manual update must also be requested when you change a preset or change a parameter via MIDI CCs from another application or source.
  • All sysex files must use .syx as file extension.
  • On larger screens, the window width can be increased to improve the resolution of the sliders.

Known Issues

  • The connection state is not always detected correctly when the Töörö is connected or disconnected while the application is running.
  • Resizing the window height is possible but has no use.
  • Using more than one Töörö at a time is not supported.

Runtime Requirements

The following platforms were tested during development:

  • Windows 10
  • OS X 10.11 (El Capitan)
  • macOS 10.13 (High Sierra)
  • macOS 11 (Big Sur)
  • Linux Mint 20.3

Building from Source

See separate document for detailed instructions.


Published under the MIT license. All contributions to this project must be provided under the same license conditions.

Author: Oliver Rockstedt


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