Doctor’s Dose – Key Velocity:
How does a keyboard know how hard—or rather, how fast (with what velocity)—a key is pressed?
The contacts consist of two parts: some pads on the circuit board beneath the keys, and little rubber nubs that get compressed when a key is pressed.
It’s those black dots that hit the circuit board and complete the contact.
As you can see, they’re offset from each other, so they land one after the other.
The processor that controls everything continuously scans the contacts (and often all other buttons) at a very high frequency and detects the time gap between the first and second contact on the given key.
The shorter the time, the higher the velocity.
The keyboard does its thing, and we’ve got a MIDI note-on with note and velocity data on the MIDI output 😄
Stay tuned for later, where new topics will be covered.
