Now turn the unit upside down such that the unit is resting on the potentiometer knobs.

The switches should fall forward and press nicely against the front panel. To make sure gently tap the unit while upside down and poke the legs of the switches.

Apply a small amount of solder to two of the switch legs. Turn the unit over, if the switch appears to be wonky or rubbing against one side you can heat up one of the joints and apply light pressure to correct the alignment. Repeat for each switch until happy and then solder all the legs.

Install the feet by pressing the rubber tube onto the long section of the cut-outs on the bottom edge of each side panel.

Pressed on.

And keep pushing until it snaps over the short nub.

time for TESTING!!


After powering it up the LFO led should respond to the position of the rate knob, if it doesn’t disconnect the power and check the LED polarity.


Connect the output to an amplifier/powered speaker. Set the sensitivity and decay to maximum and trigger the drum using a finger. Adjust the VOLUME trimmer to taste, clockwise for less, anti-clockwise for more.


VCA ADJUSTMENT: Turn the VCA trimmer fully clockwise, you might be able to faintly hear the VCO. Slowly adjust the trimmer anti clockwise until you cant hear it anymore.


At this point you should be able to trigger the drum synth by tapping it with a finger, if it does not trigger adjust the sensitivity.


Power In – The power socket accepts centre positive, 5.5mm outside 2.1mm to 2.5mm centre and voltages between 9 to 12V DC.

Power Switch – Switches the unit on and off. The power indicator LED is just below the switch.

Attack Switch – Switches the attack sound on or off, which is supposed to mimic the sound of a drumstick hitting a skin. It works to varying degrees and is dependent on the other settings.

VCO Shape & LFO Shape – Select triangle or square wave.

SENS (Sensitivity) – Sets the sensitivity of the trigger/piezo input.

Decay – Sets the decay time, from really punchy to lingering.

Rate – Controls the frequency of the LFO.

Depth – Controls the amount of LFO applied to the VCO.

Pitch – Controls the pitch (frequency) of the VCO.

Sweep – Controls the amount of frequency sweep applied to the VCO.

Sweep Direction – Selects the direction of the frequency sweep.

Trigger [Input] – Apply external rising edge between 3V to 9V to activate the drum. Experiment with the sensitivity knob to find the right trigger level.

Pitch CV [Input] – Apply between 0V to 5V to control the VCO pitch. Use the pitch knob to find the sweet spot for your external equipment.

Output – A line level output designed to be fed into a powered amplifier/speaker. Should not be used to drive headphones or low impedance equipment.

examples to get you started...

These can be printed along with some blank ones for you to fill in with your own ideas by downloading the instructions and printing the last few pages.


1 2 3 4