workout-timer uses mixalot to emit clock clicks and gong sounds. It is programmed for a 7-minute workout, but you can easily modify the source file timer.lisp to adapt the timer to your needs.
It was originally written by Fare Rideau using free sound samples from freesound.org.
Browse the source code, or get it with:
git clone https://gitlab.common-lisp.net/frideau/workout-timer.git
audio