µTune (microTune, muTune, uTune) – modular multitool

Description | Features | User Manual | Order online | FAQ


Tubbutec µTune is a powerful quantizer, midi to CV interface, CV to midi interface, midi router and general multitool with a lot of features. The two channels of the main module can be expanded to up to 8 channels using µTune expanders. µTune has many features dealing with microtonal music or generally precise pitch: You can load, edit and save scales and tunings, it includes a tuner, VCO calibration and even real-time automatic tuning.

Main features

  • Two independent channels, up to 8 channels with expanders, complete microtonal support.
  • Multi channel Midi to CV/Gate interface with various voice assign modes. MPE compatible.
  • A multi channel microtonal quantizer / mapper
  • Multi channel CV/Gate to midi conversion sends microtonal midi
  • A built in scale editor to conveniently edit, load and save scales from an SD card
  • Midi router/merger to route midi note and clock data independently between USB, DIN midi and µTune
  • Midi to microtonal midi conversion.
  • Automatic closed loop VCO tuning keep your VCO in tune at all times.
  • Built in clock generator with multiple outputs.
  • Automatic trigger output from quantizer
  • Freely configurable inputs and outputs. Can detect if input is plugged in and change behaviour accordingly which makes the module extremely flexible
  • 10 point VCO calibration to linearise VCO CV response
  • High precision 16 bit outputs, resolution about 0.15mV / 0.2cents with a voltage range of 10V
  • Built in two channel tuner with a wide pitch range
  • V/Hz mode with adjustable precission
  • Peripherals: 2x analogue in, 2x analogue out, 2x digital in, 2x digital out, Mini USB B device midi in/out, DIN midi in and out
  • Also features: Midi monitor, various alternative note notations, midi note on and off velocity mapping, adjustable midi base notes, transpose and shift scales via CV, pitch bend in, scale masks, and much more…
  • Designed and made in Germany
  • Comes with: SD card with pre-installed scales, USB Cable Mini B to type A, Eurorack power cable
  • For a complete list of features please refer to the user manual.

Some features in more detail

Quantizer / Mapper

CV inputs are quantized with adjustable V/Octave step size and use a hysteresis to achieve stable input detection. The detected input value can be mapped to scale degrees, but can also be used to transpose or shift the scale of an other channel. The quantizer can run in continuous, gated or triggered mode.

Midi to CV interface

Tubbutec µTune contains a complete two channel midi to CV/Gate interface. It features various assign modes, such as dual monophonic, multiple polyphonic and random. Mono mode features a ‘last’ note priority encoder which memorizes the last 16 notes. It is also possible to output midi clock and start/stop signals as well as link an output to a midi controller.

Scale editor

The powerful scale editor lets you easily create and modify scales. For each note of a scale you can edit the pitch in cents, fractions or select from a list of common intervals. Scales not based on the octave are possible and up to 128 notes per scale are supported. The editor contains a short cut to quickly create EDO scales. You can change the root of a scale via a shift value and deactivate notes to create ‘sub-scales’. The scales are stored on the SD card in the popular Scala format, so it is possible to use them elsewhere.

File browser

The built in file browser lets you navigate the SD card, load and save scales and vco calibration data. While navigating it shows a preview of the scale you have currently selected. It is a planned feature to also create, move and delete files and directories.

VCO calibration

No analogue VCO has a perfectly linear CV to pitch response. A built in 10 point VCO calibration curve makes sure your VCO has better linearity over the full range of 10 octaves. For calibration the internal tuner is used to track the pitch of the VCO and adjust the output voltage accordingly. VCO calibration data can be saved and loaded from the SD card. We are currently working on an automatic VCO calibration procedure as well as a closed loop continuous pitch correction for µTune.

CV to midi interface

Tubbutec µTune contains a two channel CV/Gate to midi converter. Quantizer output and gate input signals are mapped via the current scale and sent to midi-out as micro tonal midi messages using note on/off and pitch bend messages.


Tubbutec µTune includes a two channel tuner / frequency counter. You can use it to tune and calibrate your VCOs. The picture on the right shows the ‘overview’ screen with detected frequencies, input and output notes and the loaded scale.

MIDI router

A flexible midi router and merger lets you route midi note and real-time messages independently. This turns µTune into more than one tool: you can for example route the USB in to DIN midi out, but have the quantizer on channel run independently. Map CV in 2 is mapped to USB out, but DIN midi in controls CV out 2. You get the idea, possibilities are endless…

V/Hz mode

µTune features a versatile V/Hz mode to directly control vintage synths with linear, rather then logarithmic CV inputs. This has been successfully tested with several synthesizers including Korg MS10, Korg MS20 and Yamaha CS-15.

Firmware update from SD card

Firmware updates with new features can be easily performed by putting a file on the SD card and starting the update. We have many ideas ans are looking forward to make this module even better.

Flexible I/O configuration

Tubbutec µTune can detect wether an input is used and change the configuration accordingly. For each of the four possible modes (cv and gate not plugged in, cv only plugged in, gate only plugged in and both plugged in) you can configure the function of each input and output. This can be done in a simple way which is sufficient in most cases, or you can specify the behaviour in full detail.
Here is a typical example:
– If neither CV-in nor Gate-in are used: CV-out and gate-out are used as midi to cv interface.
– If you then plug in the CV-in, the module switches to continuous quantizer mode, Gate-out sending midi clock date
– Plug in the Gate-in as well and you have a gated quantizer
– Plug in the gate-in only and it is used to randomly transpose the output pitch.But of course much more is possible.These I/O functions are currently supported:
CV out: microtonal pitch, velocity chan1, velocity chan 1/2, after touch chan 1/2
Gate out: Midi gate, midi clock, midi start/stop, pass from input
CV in: map to pitch, transpose chan 1/2, shift scale chan 1/2
Gate in: quantizer trigger, quantizer gate, measure frequency, trigger random transpose chan 1/2

Technical data

  • Printed aluminium front panel, 2mm thickness
  • Supply voltage: +-12V and/or +-15V
  • Supply current: +12V: 50mA (depending on the SD card up to 100mA), -12V: 15mA, 5V: 0mA
  • Dimensions: 3HE, 8HP, 128.5mm x 40mm, Depth: < 30mm (including power connector)
  • 16Bit DAC, resolution ~0.15mV or 0.2cents
  • Input / output voltage range 0..10V (10 octaves)
  • Digital outputs: 0V/5V or 0V/12V (selectable by jumper)
  • Digital inputs 0..15V (High at about 1.5V)
  • 1.3” 128×64 OLED display
  • Weight: 82g


Does the tuner function with waveforms different than square or saw?
Pitch detection works with any common waveform: square, saw, triangle, sine, etc. But not with waveforms which have multiple riding zero crossings per period. If you have a FM waveform, I recommend turning down the modulator, calibrating and turning it up again.

What is the precision of the tuner?
Precision is much better than 0.1Hz but precision of the reading also depends on how stable your VCO is. The tuner uses filtering to get a stable reading, but if your VCO has a very unstable pitch, the reading will fluctuate.

User manual

A complete user manual for Tubbutec µTune can be found as pdf here:

>µTune user manual for firmware v2.06 (PDF)
>µTune user manual for firmware v1.xx (PDF)

Buy µTune

Schneidersladen, DE

Perfect Circuit, US

Signal Sounds, UK