How it works
This 15/8 time signature metronome counts the dotted quarter note: five beats a bar, two quieter ticks after each. Wikipedia's Quintuple meter article says compound quintuple metre, five beats of three, is most often written in 15/8.
Read the full guide
Start
Tap the pad, or press Space, and count to five on the louder clicks, from the highest. Tap again to stop.
Change the tempo
Tap the number under the pad and type the dotted-quarter tempo, or use minus and plus. A mark that counts eighth notes is divided by three first, so 150 goes in as 50. The pad stops at 333.
Questions and answers
Is 15/8 counted in five or in fifteen?
In five, on this 15/8 metronome. Open Music Theory gives the beat of a compound bar over 8 as a dotted quarter note, worth three eighth notes; fifteen hold five of those.
Is 15/8 always five beats of three?
No. Wikipedia's Quintuple meter article also pictures the bar as three beats of five, and reports uneven groupings: 3+3+3+2+2+2, and 2+2+2+2+2+3+2 in two ancient Greek hymns. This pad clicks five threes; for other music, follow the highest click.
Is 15/8 just 5/4 with triplets?
It can be written so. A 5/4 beat splits in two, a 15/8 beat in three. The Quintuple meter article says five beats of three may be notated as triplets on every beat of a five-beat bar, or as alternating bars of 6/8 and 9/8.
Where does 15/8 turn up in classical music?
Not often: the article calls compound quintuple time less frequent than the simple kind. It cites Brahms's Piano Trio No. 3, whose third movement has a middle section in 15/8 with turnarounds in 9/8, and a recurring pair of 15/8 bars in Debussy's Fêtes.
Why can't I hear the metronome?
It may be the phone and not the page: look at the ring switch, the volume, and whether Bluetooth is sending the click to headphones out of earshot. The fifteen dots light in order all the same, the five beats drawn larger than the ticks.