why do certain chords in music sound “better” than others?

Question

So I don’t know a ton about music theory, but I’m curious about how this works. Why do our brains like to hear chords that are in tune? And how do we explain why something is tuned properly?

In: 32

Answer 1

Definitely not ELI5, but this article is one of the best I have read which tries to explain “why” music works. I’ll try to summarize the very basics of it:

To survive, we need to be able to distinguish between different sounds. There is a part of your brain that compares sound frequencies and decides if they are the same or not, and how far apart they are if they are not the same.

Audible frequencies cover a HUGE range. It would be inefficient to have “hardware” in your brain that can work over that entire range. So, your brain only does the comparisons over a limited range of the audible frequencies. But, it divides or multiplies by 2 the frequency of any sound that falls outside that range, until the new frequency IS inside the range.

This means that sounds whose frequency are related by a factor of 2 get flagged as being “the same”. These are octaves. We interpret these as sounding “good” together.

From there, the article shows that the simpler the ratio between the frequencies of two sounds, the “better” it sounds. So a ratio of 2 (the octaves) sounds great, 3/2 is pretty good, 5/4 is not bad, and it gets “worse” from there.

I cannot keep the rest of it simple, but for a variety of reasons, we don’t build instruments that perfectly match these ratios, and things get complicated the more notes you play, and your brain can play tricks to “fill in” missing frequencies in a sequence. Highly recommend studying the article if you find this interesting. It really helped me make sense of apparently arbitrary music notation and theory.

[Harmony Explained: A Progress Towards A Scientific Theory of Music](http://chrome-distiller://2dc3a6c0-91fd-4cc8-8090-5aa6f47e82c2_b1fabce9e4e980408c2d35279c81722a34e89d7f1e2aa1d3f5ad4fdf6e062b0b/?title=Harmony+Explained%3A+Progress+Towards+A+Scientific+Theory+of+Music&url=https%3A%2F%2Farxiv.org%2Fhtml%2F1202.4212v1)