Audio Damage Boomtschak User Manual

BoomTschak User’s Guide

Audio Damage, Inc.

1 November 2016

The information in this document is subject to change without notice and does not represent a
commitment on the part of Audio Damage, Inc. No part of this publication may be copied,
reproduced or otherwise transmitted or recorded, for any purpose, without prior written
permission by Audio Damage, Inc.

© 2016 Audio Damage, Inc. All rights reserved.

1. Brief Overview

BoomTschak is an Eurorack module for synthesizing drum and percussion sounds. It contains a
VCO, three envelope generators, a noise source, a multi-mode VCF, and several VCAs. Its

circuitry is completely analog.

Below is an image of its panel and a description of the controls. This summary will cover just
about everything that you need to know to use BoomTschak, but after this summary we’ll

provide more detailed descriptions and some background information.

If you can’t stand reading manuals, we’ve got you covered. There’s a video providing an
overview of BoomTschak’s operation on YouTube here:

https://www.youtube.com/watch?v=2h267q8DlFY

1.1. Knobs and Switches

– sets the frequency of the VCO

– controls how much the pitch-bend envelope generator changes the frequency of

the VCO. This is a bidirectional control; at its center position, the EG has no effect on the VCO.

– sets the decay time of the pitch-bend EG.

– varies the shape of the pitch-bend EG from a sharp exponential curve to a

linear ramp.

– sets the decay time of the envelope generator which controls the VCA for the

VCO, and hence how long the VCO tone is heard.

- varies the shape of the VCO amplitude EG from a sharp exponential curve to a

linear ramp.

Switch – switches the VCO output between a triangular wave and a sinusoidal wave.

– changes the brightness of a short click added to the beginning of the sound.

– controls a simple wave-folder which changes the shape of the VCO’s signal.

– sets the frequency of the multi-mode filter for the noise source.

– sets the resonance of the filter.

Switch – choose the source of modulation for the filter frequency. There are three

options: the amplitude envelope generator for the noise source, the pitch bend oscillator for the

VCO, and the VCO’s signal.

– controls how much the modulation signal selected with the MOD SOURCE

switch changes the filter frequency. This is a bidirectional control; at its center position, the filter

frequency will not be changed by the modulation signal.

Switch – chooses one of three filter response modes: low pass, band pass, or

high pass.

– sets the decay time of the envelope generator which controls the VCA for the

noise source, and hence how long the noise is heard.

– varies the shape of the noise amplitude EG from a sharp exponential curve to a

linear ramp.

– varies the relative loudness of the VCO and the noise source. At its center position, the

noise source and VCO have roughly equal loudness. Rotate the knob counter-clockwise to hear

more of the VCO, rotate it clockwise to hear more noise.

– sets the overall output level of the module.

Button – press this to trigger the module manually. Use it while setting BoomTschak’s

knobs or for live improvisation.