Mixer/Trigger Preprocessor


mixtri(x) is a matrix mixer and trigger processor intended to be used with the oscilloscope, but also useful for other applications.

The signal flow is visualized in the GUI, left to right, top to bottom; see the (false color) screenshot below:

Input Stage

Mixtri(x) allows to mix four audio input channels to four audio outputs. Every input has a delayline (0 - 192K audio-samples), a mute-button, a high-pass filter to remove DC offset (5Hz, one-pole) and a -60dB to +20dB amplifier.

Matrix Mix Stage

The matrix mixer allows to mix any of the 4 input channels to output busses 1 to 3 with a gain variation of -20dB to +20, optional phase invert. Clicking the gain knob cycles between "add" (gray knob), "off (-inf dB)" (black, flat) and "subtract (invert polarity)" (red knob) states.

Output Stage

Every output bus has an additional delayline (also up to 192K audio-samples) to align the summed outputs.


The 4th output is intended to serve as trigger channel. Only a single input can be assigned to it. The signal is processed with various trigger algorithms detailed below. The output of this channel is always a one sample peak {0.0 ,1.0, 0.0} when the trigger-algorithm fires. Exceptions to this are the "signal passtrhu", "RMS" and "Low Pass filter" modes.

For convenience, the trigger mode documentation is built in ("Show Doc" checkbox).

Trigger modes



screenshot screenshot