And the beat goes on...forever?

Hip-hop music is usually around 80 beats per minute (bpm). Pop music is faster, around 120 bpm, and dance music can be anything from 120 up to around 200 bpm. But what if you had a beat that kept speeding up forever? How fast could you possibly get without it just becoming a blur?

The composer and computer musician Jean-Claude Risset came up with a way that a rhythm could keep speeding up forever, and yet however much it speeds up it sounds the same. It's actually an audio illusion as even though it sounds like the music is speeding up, you are just listening to the same music on a loop. It's done by combining different versions of the rhythm at different relative speeds (for example, 30 bpm as well as 60 bpm, 120 bpm, 240 bpm...) so that as the beat speeds up, different "layers" can take over as the main rhythm we perceive.

Music researcher Dan Stowell from Queen Mary's Centre for Digital Music has come up with a way to apply Risset's effect to any breakbeat rhythm and you can try it out.

Download the MP3 here

Listen to the beat - tap along and see how fast you can get...then pause for a few seconds and start again. Has the beat weirdly gone back to being slow again?