The program will play a tempo, like a metronome. You should try to guess how many beats per minute is played. Each button represents one tempo, and the program will only play in tempos that has a button with bold text. Right-click on buttons to change the status of a tempo.
Rimarko: la ritmo dependas je la funkcio gtk timeout_add
por ludi la ritmon, do ĝi ne estas tiomege ĝusta.