Dave from Bitwig walks through the math behind building a key-tracked delay in Bitwig Studio's modular environment, showing how to convert MIDI note values into precise millisecond delay times so the delay resonates in tune with whatever note you play.
The core challenge is that pitch is linear while frequency is logarithmic, and bridging that gap is where most of the work lives. Two modules handle the heavy lifting: Pitch to Frequency converts the incoming note signal into hertz, and Reciprocal flips it to get the period. Switching the Reciprocal's unit to kilohertz takes care of the thousand-times scaling difference between hertz and milliseconds.
The final patching detail is about unit control inside the delay itself. Setting the delay's base time to exactly one millisecond, then modulating it at 100% with an attenuator, lets the converted pitch signal take full control of the delay time. Subtracting that one millisecond of bias keeps the values clean and on target, giving you a delay that tracks octaves as you play up and down the keyboard.