A4 Master Clock With Count-in

Master Clock

This is an Audulus version 4 master BPM clock with count-in and an external sync. It can be set from 20 to 200 BPM (beats per minute). It outputs variable pulse width clocks from 1/64 notes to 64 bars.There is a count-in which can be set to 0, 1, 2, 4 or 8 1/4 note beats. A count-in output is provided for a click if desired. The sync/external input works as follows: When the External toggle is off the sync input acts as a normal sync and resets the phase to 0 but does not adjust the BPM. When the External toggle is on, the clock will calculate the BPM of the incoming sync signal and adjust its own BPM to match. In this case it assumes that the sync signal is a 1/4 note beat clock.
The run and ext toggles have an input to allow the toggles to be controlled by an external signal. There is a pulse width knob that can adjust the duty cycle of the clock signals from 1 to 99% and an external reset input


Input Signal Range Notes
sync/ext 0-1 clock or gate when ext is off acts as a sync, when on will adjust the BPM tp match an incoming beat clock
reset 0-1 gate resets the clock
Output Signal Range Notes
cnt in 0-1 clock provides a beat clock for the count-in.
clock outputs 0-1 clock variable width clocks from 1/64 notes to 64 bars


Control Function Notes
BPM beats per minute sets the tempo of the clock in 1/4 note beats
cnt in count-in count-in for the clock start - 0, 1, 2, 4, or 8 beats
Ext toggle to control ext/sync input see description above - input also provided
Run run/stop control for the clock input also provided

Version History

Revision File Date Notes
A4 Master Clock V2.2.audulus4 (68.7 KB) 12/14/2022 A4 version of existing A3 clock module

Fantastic work! I think putting the lights behind the outputs works nicely too, I was sort of torn between the two styles for the library.

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That external sync setup is cool!


It uses a zero-crossing node to calculate the bpm. It takes a couple of beats to stabilize, but it allows you to subdivide an external beat clock.

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