MIDI-Tap Tempo Tremolo

Abe's Custom Effects:

MIDI-Tap Tempo Tremolo

I wanted to share this project ever since it was completed but life got in the way :)  This was a very cool project because an artist finished the pedal with incredible artwork and looks awesome!

This was a custom tremolo build request that required MIDI clock input, Time Division selection (from whole notes to eighth notes), different wave selection (sine, triangle, etc), and able to run off from 12V 400mA power supply.  Also the requester wanted all the jacks on the north side of the pedal.  As we started communicating, it made sense to add the Tap Tempo switch for ease of setting the tempo. 

Here is a picture of the enclosure (top left) and freshly etched circuit board (bottom left) before it was worked on.  The blue enclosure and the circuit on the right side is a custom Blues Breaker build with couple modifications that I've added.

I designed the pedal to work with LED/LDR combo driven by digital LFO to accommodate MIDI clock and Tap Tempo inputs.  The audio signal is still completely analog, providing nice warm tremolo effect.  This pedal also benefits from being run at 12V for slight advantage in headroom.

Due to the nature of digital controllers, I had to be careful isolating digital and analog grounds to keep the digital noise out of the audio signal.  I also used couple heavy duty Voltage Regulators to prevent any failures down the road due to heat.  Here is a picture of the circuit board after all the components have been populated:

The pedal end up drawing a little less than 200mA but it's well below the power supply limitations.  There are two LEDs; one for ON/OFF indicator and the other "blinks" in time according to how SPEED is set.  Here is a picture when I finished it up (left pedal is an external tap switch that could connect up to 3 different pedals at once):

Painting in progress: