Tap Tempo Synchronizer


The MCC-3t produces a MIDI clock and discrete digital pulse output to synchronize various types of musical instruments. The clock rate is set by measuring the timing of a "tap" switch input.

MCC-3t front panel photo
MCC-3t front panel photo


Power -- connect the supplied AC to DC adapter to the power input jack.

MIDI out -- If you are synchronizing a MIDI device, connect a standard MIDI cable between the MIDI output on the MCC-3t and the MIDI input of the target device.

Clock Out -- If you are synchronizing another device which uses a TTL level clock, connect a standard mono audio cable (TS type) from the Clock Output jack on the MCC-3t and the clock input of the target device. This might be a modular synthesizer sequencer, a synthesizer arpeggiator with external clock input or a drum machine without MIDI capability, for example.

Tap input -- The tap source can be a digital logic signal from another clock source, a normally open momentary footswitch, or even a drum pad with piezo trigger output. The tap input is optional, if you set the tap rhythm using the pushbutton on the rear panel of the MCC-3t.


For each tap interval, a selected number of clock pulses are generated. The number of pulses is selected using the up/down pushbuttons and indicator lights on the front panel of the MCC-3t. Use the chart on top of the MCC-3t to determine the output rate, based on the illuminated lights. Use the pushbuttons to change the setting. The MCC-3t will remember your setting when the power is off, so you may only need to set this up once. For a standard MIDI clock, with one tap per quarter note, set the rate to "24".


When the MCC-3t is first powered up, the tap rate defaults to 60 beats per minute, multiplied by the current user setting.

To set a new rhythm, press the tap switch at least two times in sequence. Pressing the tap switch more times in a steady rhythm will produce a more accurate timing. Each tap interval is averaged with the previous interval to smooth out changes in tempo. When making a large cange in tempo, it may take several taps to get the desired tempo. When tapping stops, the clock output will continue free-running at the current rate.

MIDI clocks

The MCC-3t can produce MIDI song start and stop commands, as well as the free-running MIDI clock. The start command is sent after the first two taps are detected. To send a MIDI stop command, you can press one of the clock rate selection buttons. For example, press the "up" button, followed by the "down" button to send a MIDI stop command and leave the clock rate at its original setting.

Tap Polarity

The MCC-3t comes set for a normally high clock signal or normally open switch (sometimes know as "S-trigger"). You can change this to use a normally closed switch or normally low clock signal (V-trigger) by changing the setting of the slide switch inside the MCC-3t case. You will need to open the case to reach this slide switch. To open the case, remove two screws from the front of the unit, remove the front panel, and slide the top forward. Once the switch selection has been made, close the case by reversing these steps.