uniPulse – universal drum machine midi interface

Now in version MK3, see comparison

Description | Features | Sound demos | User Manual | Order online | FAQ | List of supported machines | Installation manuals


Main features

  • Highly customizable, compatible to almost any drum machine.
    A list of compatible machines is below.
  • 16 pulse outputs
  • Full velocity sensitivity
  • 5 different pulse shapes
  • Outputs positive and/or negative pulses up to 15V/-15V
  • Voltage and length can be mapped to velocity, controller or CV-input
  • 7 Digital outputs for gates and clocks
  • Up to 24 simultaneous clock outputs with different midi dividers
  • Analog output with various functions
  • Potentiometer / CV input to control length or voltage of pulses
  • Internal clock multiplier for DIN sync
  • Easy to use configuration app with preset database for common drum machines
  • Very small, fits in most drum machines
  • Various midi socket configurations
  • Runs off a single supply voltage between +7 and +25V, generates negative voltage internally

Some features in more detail

Pulse shapes

Various pulse shapes can be selected for each output: Rectangular, Triangular, Decay, Gaussian and Open Rect. The latter is similar to the rectangular pulse, with the exception, that instead of returning to zero volts, it goes into a high impedance state. This allows it to make use of the characteristics of an existing pulse shaping network, such as an RC network built into the drum machine.
The pulse shapes have different sonic characteristics, experimenting which suits best is recommended. The Gaussian pulse for example contains less higher harmonics and can be used to simulate drums hit by a felt headed mallet.

Clock and sync gates

The analogue output and the four digital outputs can be configured to act as sync clocks and gates. This allows it to sync the drum machine to the midi clock. Clock dividers and polarity are adjustable in order to achieve compatibility with all drum machines. Clocks speeds between 48PPQN (din-sync 48) and 1PPQN (one pulse per quarter note) are possible.
By using the 16 pulse outputs, the uniPulse can output up to 21 different clocks simultaneously.

Configuration program

The uniPulse configuration program, available for windows and OSX, uses midi sysex to configure the uniPulse. We are constantly working on expanding a database of presets for common drum machines.
For each channel, you can select pulse shapes, polarity, length, midi channels, note numbers and mappings. For sync outputs clock dividers can be chosen.
A velocity sensitive test button an be used to instantly listen and refine your configuration, and thus choose what sounds best for your particular drum machine and taste.The program can be found here: uniPulse Configurator


User Manual

The general uniPulse manual (PDF) describes the unipulse functionality and specifications and gives some generall recommendations of how to interface various types of drum machines.

The old MK1 user manual can be found here.

Additionally installation manuals exist for specific drum machines. A list of these manuals can be found here:
uniPulse drum machines overview

You can help expanding this database and help other users with the same machine. This will be rewarded by Tubbutec with a discount on your next order. Thanks a lot for contributing!
See: uniPulse contribution.

Order online

uniPulse can be ordered online in our shop. We ship from Germany with fixed shipping costs worldwide. If you want us to install the mod for you please contact us.

The kit contains the uniPulse board, ribbon cable with connector, stencil for hole drilling, all necessary screws and external midi socket with connector (if specified).

Please note: The uniPulse installation requires some electronic knowledge, especially if there is no specific installation manual for your drum machine yet. Please only order if you are sure you can install it. Read the general manual to get an idea about the uniPulse and what it requires to install.


  • Q: Will my drum machine sound exactly the same when triggered with the uniPulse?
  • A: Most likely yes. The different pulse shapes, especially the ‘Open Rect’ shape will get you as close to the original sounds as possible
  • Q:I have multiple machines, but only want to buy one uniPulse. What can I do?
  • A:You can put the uniPulse in an external box, install external trigger inputs in your drum machines and connect them.
  • Q:Firmware update?
  • A:Yes. The firmware can be updated using midi sysex
  • Q:How and where is the UniPulse retrofit produced?
  • A:The uniPulse is designed an manufactured in Germany. Only lead free components and solder are used.
  • Q: Is my drum machine supported?
  • A: Very likely yes. Below is a very incomplete list of supported machines.

Installation manuals

This is an incomplete list of drum machines which can be controlled with uniPulse. If your machine is not on the list, please contact us.
If there is an installation manual available for the particular machine, click the name to get to the uniPulse installation manual. No link means installation is possible, but we don’t have a manual yet.

Ace Tone

Ace Tone Rhythm Ace R-3
Ace Tone Rhythm Ace FR-1 (Goya melodic rhythmer)
Ace Tone Rhythm Ace FR-2
Ace Tone Rhythm Ace FR-3
Ace Tone Rhythm Ace FR-4
Ace Tone Rhythm Ace FR-6
Multivox Rhythm Ace FR6M
Ace Tone Rhythm Ace FR-7
Ace Tone Rhythm Ace FR-8
Ace Tone Rhythm Ace FR-13
Ace Tone Rhythm Ace FR-106
Other Rhythm Ace machines


Roland CR-68
Roland CR-78
Roland TR-808 (Special TR-808 version available)
Roland TR-606 (Special TR-606 version available)
Roland CR-5000
Roland CR-8000
Roland TR-33
Roland TR-55
Roland TR-66
Roland TR-330
Roland TR-77
Roland PB-300


Tama Techstar


Vermona ER9
Vermona DRM (1987)


Yamaha MR10

Linn Electronics

Linndrum (not velocity sensitive)


Hammond AutoVari 64


Keynote AutoRhythm
Jax 230 Auto Rhythm
Selmer MR-101 Auto Rhyth


All e-drums can be directly interfaced via their trigger inputs. uniPulse can be installed internally in the machine and trigger wires connected to the triggers. Or you could put uniPulse in an external box and connect it to the simmons machines via jack cables.
SDS 3, SDS 4, SDS 5, SDS 6, SDS 7, SDS 8, SDS 9, SDSV
Video of an SDS7 – note the velocity sensitivity
Another video of an SDS7
An SDS5 with uniPulse Midi
Another SDS-5
Analog Claptrap
Digital Claptrap