Metronome: a device used by musicians that marks time at a selected rate by giving a regular tick. If you ever felt that you missed a metronome in Impromptu, here is a little scheme object that can do that job for you.

The make-metroclick function returns a closure that can be called with a specific time in beats, so that it plays a sound for each beat and marks the downbeat using a different sound.

Possibly useful in order to keep track of the downbeats while you compose, or just to experiment a little with some rhythmic figures before composing a more complex drum kit section.

Here’s a short example of how to use it:

Make-metronome relies on the standard libraries that come with Impromptu, in particular make-metro, which is described in this tutoriale and on this video. Essentially, it requires you to define a metro object first, e.g. (define *metro* (make-metro 120)).

Here’s the source code: