Rhythm & Detonation

Tap Tempo Tremolo

This is a great project supported by Taylor over at musicpcb.com.

The tap tempo tremolo is the first and only DIY trem project that allows you to tap in the rhythm with a foot-switch. This capability makes it easy to synchronize a rhythmic trem to the beat of your song. Besides that, it’s a great-sounding trem, and certainly among the most versatile tremolo circuits.

The TTT covers territory from smooth and deep “throb”, through the classic “repeat percussion effects” to hard chopping square wave. It features eight different waveforms, and the wave distort function allows one to change the character of each wave drastically.

The TTT uses a digital micro-controller to do the tap tempo and create the waveforms. It then uses an opto-coupler to control volume. The audio path remains analog all the way through, while giving you the complexity and versatility of digital control.

This was a really fun build, and it sounds great. The TAPLFO micro-controller actually makes it easier to build than a standard LFO tremolo.

For the artwork I used an image of the Inversion House,  an art project in Houston that happened a few years back in which two artists "inverted" a house. I painted the enclosure automotive white and used a super bright blue LED for tap tempo, and a super bright red LED for the true bypass. I used white Davies 1510 knobs and a Hammond 1590BB-sized enclosure.

The controls for the effect are TEMPO, which controls the rate of the tremolo effect; WAVEFORM, which selects one of eight waveform shapes (ramp up, ramp down, square pulse, triangle, sine wave, sweet, lumps, and random); MULTIPLY, which selects the subdivision factor for the tap tempo switch, quarter notes, eighth notes, triplets, sixteenth notes, sixteenth note triplets, or thirty-second notes; and DEPTH, which selects the depth of  the tremolo effect.

Inside the pedal is a trim pot to control the overall volume of the pedal so you can match the effect pedal to your bypass level or boost the effect level if you want.