Number of Possible Songs

Will we ever run out of new music? The quick answer is no, and this page delves into why. The Skiptune database of tunes, which is far from complete, already has 486 duration ratios.  Each duration ratio has the potential for 85 pitch changes.  That means that there’s a choice of 41,310 pairs of notes for each note that a composer adds to a melody or tune.  A relatively short melody, such as the children’s song Bingo, has around 25 note changes.  So for a composer writing a 25-note tune, he or she has a choice of over 41,000 different note pairings to choose from each point along the way.  The total number of possibilities, then, is 41 ,000 to the 24th power (because there’s one fewer pairs of notes than total notes).

This computes to over a googol number of possible tunes.  A googol (not the search engine) is a 1 followed by a 100 zeroes.  To put it in perspective, the number of atoms in the observable universe is 1 followed by only 80 zeroes.  The number of unique chess games possible is a 1 followed by only 50 zeroes.

Admittedly, the vast majority of these possible “songs” would sound like noise to us.  But today’s music would have sounded like noise to medieval listeners.  Music evolves, and it evolves by adding notes that have not followed the previous note.  The Skiptune project provides much evidence for that form of evolution.  The notes themselves don’t evolve, but the patterns they make up do.  In the findings menu, for instance, we show how new pairs of notes are added over the centuries.

So the real answer to the question, “How many songs are there?”, is unknown because we don’t know the extent of our ability to add new pairs of notes that still sound pleasing to our ear.  But at least we don’t have to worry about “running out of notes.”