https://zeppelindesignlabs.com/product/quaverato-harmonic-tremolo-pedal/
Quaverato Harmonic Tremolo Pedal combines many features to make a great sounding, versatile, and practical stompbox. Available as a DIY KIT or Ready-to-Play (select below).
Digitally controlled, all analog signal path combining maximum flexibility with great tone.
Both Traditional (In-Phase) and Harmonic (Out-Of-Phase) Tremolo modes
Up to 15dB of gain
Modulates the high and low frequencies independently for dynamic swirling effects
Extra internal controls allow for custom crossover frequency selection and individual HIGH and LOW signal path volume adjustment, for full tonal control
Bypass footswitch can be used as either a toggle or momentary switch
Plus all the usual:
LFO wave shape, rate, depth and spacing (aka wave form shift or duty cycle)
Tap Tempo footswitch and multiplier selection
Relay controlled, true-bypass switching scheme