Why are there 12 different notes?

Why does a piano (and Western music in general) have 12 different notes?

When people learn an instrument, they usually take our 12-tone harmonic system for granted − it seems so natural that we never question it. But is it?

When I began searching for an answer, I didn't expect where it would take me − it became a fascinating journey through the worlds of physics, history, and human perception.

From the modes of a string to the construction of musical scales, from the circle of fifths to the mathematics of equal temperament, from perfect intervals to historic tuning systems − our search takes us to all kinds of musical mysteries.
And in one way or another, they all tell a wonderful story of human creativity and curiosity over thousand of years...

This is the first time I created an educational video about music theory − please let me know if you found it worth watching, and if you're interested in more content like this (no worries, I won't stop creating piano covers)!

Needless to say, I'm incredibly thankful for any feedback, like, and subscription!

(I arrange all kinds of music for piano: classical, oldies, pop, movie soundtracks, TV theme songs, jazz, and everything in between!)

### ADDITIONAL RESOURCES ###

If you want to do a deeper dive, here are some videos I found interesting and helpful:

Here's the great Leonard Bernstein explaining the harmonic series:

@DavidBennettPiano created the most popular video on this topic:

This video by @CaseyConnor is great for understanding the mathematical logic of the 12-tone scale:

@StevenJacks has some great visuals about constructing a scale out of pure ratios:

@SteveMould did a great video on resonance / standing waves:

### CHAPTERS ###

0:00 Introduction
0:49 Frequency & Intervals
2:38 Modes of a String / The Harmonic Series
4:46 Just Intonation
6:56 Pythagorean Tuning
9:55 Equal Temperament
11:17 Final thoughts

Spinning globe motion graphics provided by Dudu:

#musictheory #education #piano #music #musiceducation #overtones

[Montechait]

Thank you for all the wonderful feedback, really appreciate it!
Of course, you'll help me a lot if you like & subscribe.
Cheers! 💙

[gettingstuffdoneright]

I'm a PhD in music theory and I have to say this is one of the clearest and most engaging explanations I've seen, great narration, great visuals, really well done. Your explanation also describes the "harmonic" way the pentatonic scale naturally arises.

[tomoyafujiwara]

That’s why fretless instruments (like violins) sound so good because they can have perfect tuning for every key.

[DarthCalculus]

I'm a physics teacher and amateur musician. This explanation was excellent, and the presentation and production quality are top notch. Fantastic job

[cemmy]

This is it! Finally, there's a concise and easy to follow explanation of the different tuning systems and why we settled on equal temperament that I can point my non-music-theory friends to. You did a really, really great job presenting this.

[JonnyRay]

This video should be at the start of every music theory course! It all makes a lot more sense now! Thank you for explaining the WHY.

[paolosbalchiero]

One of the most entertaining, informative and overall well made videos on music theory I’ve seen

[Benoit-Pierre]

2:20 all mathematicians are already feeling the logarithm coming ...

[AndyGrahamProductions]

Love this! Can you do a video on why everything revolves around C instead of A? And why scales are broken into a strange combo of whole and half steps?

I could never get clear answers from people about those two things .

[vassilisstergioudis]

I'm neither have a PhD in music nor I am a physics teacher. But, I am a chanter in orthodox church. This is one of the reasons why we chant and not have organs inside the church. Byzantine music has different notation than european music. It does not say that A is 440Hz. What is does say is that whatever your base tone is, you use these "intervals" until you get to an octave heigher. So yes, when constructing an instrument, it's impossible to have a perfect scale. But when you use your voice, you can tottaly have it!

[tomdaoust]

Brilliant explanation. Very complex and almost too much to comprehend. I studied music theory when I was 17 years old and loved it. Now I'm 72 and much of it guides my guitar and piano playing and affects my enjoyment of music. Thanks for this great demo.

[danball]

Incredible! This is a fantastic explanation with simplicity, depth, accuracy, and clear communication. This is a masterpiece of art and science.

[kraftaculousgreekgodofcraf]

Please tell me I’m not the only one who couldn’t hear a difference at 11:15 just intonation vs equal 😭

[lacaruana]

Thank you so much. As a painter (and non-musician) I've made a deep study of harmony, but this video connects so many dots for me. The clarity of explanation and constant demonstrations are exactly what I needed, and I'll be sure to pass this on to my students. Deep gratitude....

[jonahansen]

What an excellent presentation. Covered all the important reasons and compromises that make music possible and immortal.

[jwonga]

this blew my mind, so informative and gives what i thought to be a simple scale completely new meaning. thank you for putting this together!!

[WhiteDragon]

An idea I always wanted to explore is "rounding" the key frequencies to the nearest pure interval within the musical context. So, equal temperament is used initially, but then two consecutive or concurrent notes are nudged a little to keep simple ratios with each other.

[TNYDCK]

I have explained things to my friends similarly in the past. I have to say, this is the clearest and most complete that I have seen on-line, ever.

The only enhancements I can think of are:
1) We in the West think of strings and pipes when we think of music but people in the East tend to have more of a bell and gong bias so they are not so hooked in to harmonic series.
2) For those into musical theory, the "Pythagorean Comma" could have been explicitly named to make the link. I know it was described.

[ASMRChess]

Amazing video. Deserves millions of views.

[toolebukk]

This video is absolutely perfect!! Thank you! Been a musician all my 40 year life basically, studied music theory and became a music teacher, teaching in primary and secondary. Never been exposed to such a well composed explanation of this subject before. Great job!