12 Notes

Why 12 ?

So, yesterday morning I woke up and was in a STATE ! I kept asking myself, “Why 12 notes?!!!”. It was driving me crazy!

Yup, EVERY piece of music listened to in the Western World is composed of just 12 notes: A, B-, B, C, C+, D, E-, E, F, F+, G, and G+. Well, and their harmonics (integer multiples of the frequencies (octaves). A is defined as 440 Hz (cycles per second), and each subsequent note is a factor of 2^[1/12] higher in frequency. And any instrument you buy, other than the violin, cello, or trombone, will only allow you to play these 12 notes (and their multiples)!

So, why 12 notes? Why not 5, or 19 or 24 notes? Why not an infinity of notes? Who decided this?

If you’re interested, below is a great explanation that I found on YouTube:

I think the easy answer is:

• 5 notes is two few to give all the combinations of frequencies that either “sound good” or “sound interesting”.

• More notes than 12 would allow more combinations yielding more “interesting sounds”, but no more of the “sound really good” combinations; and while the music might be richer and more interesting, the musical instruments would be far more (too) difficult to play. So, it was a compromise.

I am looking forward to hearing “new music” in the future — an A.I. (or perhaps human) composer might not be intimidated by a 19 or 24 note scale, and the artificially-created music not constrained by the available musical instruments.

And, the artificially-composed music could always adjust the tuning of the “instruments” in its orchestra on the fly from “Equal-Tempered Intonation” to "Just Intonation”¹.

1. The Equal Tempered Intonation spaces all the notes by equal factors in frequency apart. However, when you do this, harmonics of the “good sounds” are not perfect (i.e., 2^[5/12] = 1.3348 …, not exactly 1.33333…. (4/3). The only perfect frequencies combinations are the Octaves. For awhile this drove me crazy when tuning my guitar: doing an exact harmonic ratio between some strings made other strings more out of tune, and there is NO WAY to make all strings perfectly harmonically-related with all the others. I will have to ask Kade Pucket how he tunes his guitar! You can see another great Youtube Video discussing this problem of why “all musical instruments are out of tune” here.