## Music. How and why?

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userxp
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### Music. How and why?

I have always wondered what music is and why does it exist. I found some information about what parts of the brain process music (such as how amygdala damage impair recognition of scary music), and I was hoping you could help me with these questions:
• What is the evolutionary purpose of music and rhythm?
• What patterns are perceived as music?

frezik
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### Re: Music. How and why?

userxp wrote:
• What patterns are perceived as music?

That's pretty open ended. You'd have to cover it in a course on Music Theory.
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Korrente
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### Re: Music. How and why?

I've wondered about this too ever since I started playing music. I've always assumed it's a byproduct of our brain's ability to pick out patterns from seemingly random data. I think we enjoy it because it flexes your brain's pattern-recognition muscle as you have to stay on top of the sound or you tune it out completely.

Western music is much more structured until you get right down to the physics, then things stop making sense (turns out half-steps are nowhere near equal in frequency change, even though they sound like it). But when you get into some types of Eastern music, things really do get down right random and I'm sure a lot of people wouldn't even call it music. But obviously it wouldn't have lasted if someone didn't enjoy randomly hitting drums and chimes. So culture has a lot to do with how you're taught to perceive the patterns as well.

This isn't going to answer any questions, but they're some things I find interesting:
I don't think I've ever met a person who didn't think pentatonic scales sound good, and even people who can't sing worth crap seem to be naturally good at singing them. There's a great youtube video demonstrating this but I can't seem to find it.
Like I said earlier, natural scale progression doesn't go at a fixed interval like they taught us in grade school theory. Why is it that our brains still interpret this mashup of frequency changes as relevant patterns? It's all weird.

++$_ Mo' Money Posts: 2370 Joined: Thu Nov 01, 2007 4:06 am UTC ### Re: Music. How and why? Korrente wrote:(turns out half-steps are nowhere near equal in frequency change, even though they sound like it) Most people are familiar with equal tempered scales, and in that case they are equal. Of course, if you use Pythagorean tuning, they aren't exactly equal, but they are still awfully close. The Pythagorean comma is only about 1/4 of a semitone. jjfortherear Posts: 103 Joined: Wed Oct 27, 2010 12:44 am UTC ### Re: Music. How and why? I think as far as tonality goes, I'm pretty satisfied by the fact that it's based off the harmonic series (seems pretty natural, waves fitting nicely together with multiples of themselves). As far as rhythm and chord progressions, I feel like that's a lot more subjective and based upon experience. I can listen to a good progression of arpeggios all day, with no accompaniment or percussion (nothing but a sine wave would be just fine), but a lot of people find that bland. Qaanol wrote:Actually this could be a great idea. See, you just have to bill the mission to an extrasolar planet as a mission, and then let all the fundamentalists from all religions be the missionaries. acai Posts: 85 Joined: Sun Sep 07, 2008 11:57 pm UTC ### Re: Music. How and why? Korrente wrote:I don't think I've ever met a person who didn't think pentatonic scales sound good, and even people who can't sing worth crap seem to be naturally good at singing them. There's a great youtube video demonstrating this but I can't seem to find it. http://www.youtube.com/watch?v=ne6tB2KiZuk This is what you're after I think. Douglas Adams wrote:In the beginning the Universe was created. This has made a lot of people very angry and has been widely regarded as a bad move. Moose Hole Posts: 398 Joined: Fri Jul 09, 2010 1:34 pm UTC ### Re: Music. How and why? In my experience people acquire tastes for music (and music genres). For example, in high school I didn't think it was cool to listen to rap, or to my parent's easy listening. I've since grown out of attempting to fit into cliques by not liking certain music, and have learned to like both types (though I had to listen to them for a while to get to like them). I still don't like country music, but I guess if I tried hard enough I could like that too. My point is that perhaps brains are accustomed to certain musical patterns, and that it has to build the pathways to those patterns to do so. But this is just personal experience so maybe I'm wrong. Korrente Posts: 164 Joined: Thu Dec 17, 2009 5:44 am UTC ### Re: Music. How and why? acai wrote: http://www.youtube.com/watch?v=ne6tB2KiZuk This is what you're after I think. Exactly what I'm after, thanks! I was either in a band where the conductor did something very similar to this. Told one person to sing a note, another to sing the next, then the third to guess which note came next. Worked out the same as in the video. Shivahn Posts: 2200 Joined: Tue Jan 06, 2009 6:17 am UTC ### Re: Music. How and why? userxp wrote:I have always wondered what music is and why does it exist. I found some information about what parts of the brain process music (such as how amygdala damage impair recognition of scary music), and I was hoping you could help me with these questions: • What is the evolutionary purpose of music and rhythm? • What patterns are perceived as music? I think you're looking at the wrong cause when saying the amygdala processes music because damage inhibits the ability to recognize scary music. Amygdala damage can stop people from recognizing fear, knowing what afraid people look like, etc. It's far more likely that the amygdala is required to process scary music as scary because of the scary part than the music part. gmalivuk GNU Terry Pratchett Posts: 26738 Joined: Wed Feb 28, 2007 6:02 pm UTC Location: Here and There Contact: ### Re: Music. How and why? I highly recommend the book Musicophilia for questions about the brain science of music. Korrente wrote:(turns out half-steps are nowhere near equal in frequency change, even though they sound like it) They all have an equal ratio of frequencies. The fact that we perceive it on a log scale rather than linear doesn't mean the physics is crazy. (After all, that's how we hear volume and see brightness, as well.) But when you get into some types of Eastern music, things really do get down right random and I'm sure a lot of people wouldn't even call it music. Things begin to *seem* downright random to your Western cultural experience. But I'm sure if you asked someone who actually knew what they were talking about, they'd say it was possible to do wrong, which means there is an intentional pattern to it. Your inability to recognize said pattern is not necessarily indicative of anything. Also, have you ever listened to any free jazz? Pretty Western origins, and pretty random-sounding patterns. I don't think I've ever met a person who didn't think pentatonic scales sound good And I don't think you've ever talked about this with someone who didn't speak your language, which means they've had a high degree of exposure to your culture, which means you have a very biased sample for this anecdote. Like I said earlier, natural scale progression doesn't go at a fixed interval like they taught us in grade school theory. I'm still not sure what you're talking about here. Equal temperament has exactly the same ratio between half-steps. Other temperaments are different but still tend to be quite close to equal. What were you taught in grade school theory? Unless stated otherwise, I do not care whether a statement, by itself, constitutes a persuasive political argument. I care whether it's true. --- If this post has math that doesn't work for you, use TeX the World for Firefox or Chrome (he/him/his) achan1058 Posts: 1783 Joined: Sun Nov 30, 2008 9:50 pm UTC ### Re: Music. How and why? Korrente wrote:But when you get into some types of Eastern music, things really do get down right random and I'm sure a lot of people wouldn't even call it music. But obviously it wouldn't have lasted if someone didn't enjoy randomly hitting drums and chimes. So culture has a lot to do with how you're taught to perceive the patterns as well. You sure that's Eastern music you are listening to instead of a score by Schoenberg, or folk music harmonized and orchestrated by Bartok/Stravinsky, or the experimentalism of the 60's? What I meant to say is, before calling other music random, look at what Western music has done in the last 100 years. Moose Hole Posts: 398 Joined: Fri Jul 09, 2010 1:34 pm UTC ### Re: Music. How and why? There is a class of music that is not taken very seriously, discordant music, which intentionally is discordant. Obviously it sounds bad to people, at first, but I'm a little interested in figuring out if I could get used to it, or anyone else could, enough to actually like it. If so, then the pleasing pattern recognition might not only be tied to harmonics but also familiarity of any sound pattern. Korrente Posts: 164 Joined: Thu Dec 17, 2009 5:44 am UTC ### Re: Music. How and why? achan1058 wrote:You sure that's Eastern music you are listening to instead of a score by Schoenberg, or folk music harmonized and orchestrated by Bartok/Stravinsky, or the experimentalism of the 60's? What I meant to say is, before calling other music random, look at what Western music has done in the last 100 years. I didn't rule out anything Western or modern, just a good example that popped into my head was that particular style. gmalivuk wrote: Korrente wrote:(turns out half-steps are nowhere near equal in frequency change, even though they sound like it) They all have an equal ratio of frequencies. The fact that we perceive it on a log scale rather than linear doesn't mean the physics is crazy. (After all, that's how we hear volume and see brightness, as well.) Pythagorean Tuning Harmonic Series It is possible to tune with perfect ratios but it's more of an average of each change and therefore not precise. Several notes in a true harmonic series will be significantly lower in pitch than what they would be if you applied equal temperament. On top of that, there isn't an instrument in existence that can imitate an ideal string, so not only are the notes you're playing unequal in distribution, your instrument can't produce them without throwing in some amount of overtones, partials, and a mess of other unrelated sounds. So back to my point, it's a wonder you get any sort of pattern out of it at all. gmalivuk wrote: But when you get into some types of Eastern music, things really do get down right random and I'm sure a lot of people wouldn't even call it music. Things begin to *seem* downright random to your Western cultural experience. But I'm sure if you asked someone who actually knew what they were talking about, they'd say it was possible to do wrong, which means there is an intentional pattern to it. Your inability to recognize said pattern is not necessarily indicative of anything. Also, have you ever listened to any free jazz? Pretty Western origins, and pretty random-sounding patterns. I didn't rule out anything Western or modern, just a good example that popped into my head was that particular style. Yes it was a poor choice of wording. Though I think I specifically said Korrente wrote:...culture has a lot to do with how you're taught to perceive the patterns as well. Oh look, I did specifically say that. However, I never said I didn't recognize a pattern, that's the entire point of the style: they play random and you pick out pleasing patterns from it. And yes, I do enjoy the occasional Coltrane and Mingus. gmalivuk wrote:...you have a very biased sample for this anecdote. Yes. Now calm down and be nice. gmalivuk GNU Terry Pratchett Posts: 26738 Joined: Wed Feb 28, 2007 6:02 pm UTC Location: Here and There Contact: ### Re: Music. How and why? Korrente wrote:It is possible to tune with perfect ratios but it's more of an average of each change and therefore not precise. Sure, but unless you're playing pure sine waves, the differences aren't all that noticeable on a single piano or synthesizer. Several notes in a true harmonic series will be significantly lower in pitch than what they would be if you applied equal temperament. Which is why no one uses the harmonic series for tuning all the notes of an instrument. so not only are the notes you're playing unequal in distribution I'm still not clear on what you mean by unequal in distribution. Equal temperament by definition has notes equally distributed across frequencies, on a log scale, which is how we hear tone. your instrument can't produce them without throwing in some amount of overtones, partials, and a mess of other unrelated sounds. So back to my point, it's a wonder you get any sort of pattern out of it at all. You get a pattern because far and away the dominant frequencies are the ones that correspond to the length of the air column or the plucked string or whatever. Other frequencies are much lower in amplitude, so they don't much affect the perceived note of an instrument while having a huge impact on its timbre. Unless stated otherwise, I do not care whether a statement, by itself, constitutes a persuasive political argument. I care whether it's true. --- If this post has math that doesn't work for you, use TeX the World for Firefox or Chrome (he/him/his) ++$_
Mo' Money
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### Re: Music. How and why?

Korrente wrote:Pythagorean Tuning
Harmonic Series
It is possible to tune with perfect ratios but it's more of an average of each change and therefore not precise. Several notes in a true harmonic series will be significantly lower in pitch than what they would be if you applied equal temperament. On top of that, there isn't an instrument in existence that can imitate an ideal string, so not only are the notes you're playing unequal in distribution, your instrument can't produce them without throwing in some amount of overtones, partials, and a mess of other unrelated sounds. So back to my point, it's a wonder you get any sort of pattern out of it at all.
I think you are confusing Pythagorean tuning and the harmonic series. They are completely different from each other, and basically unrelated.

Pythagorean tuning with a base frequency of [imath]F[/imath] produces notes with frequences [imath]F \cdot 1.5^n \cdot 2^m[/imath], for [imath]0 \le n < 12[/imath] and [imath]m[/imath] any integer. The half steps here are very close to equally spaced -- in most cases too close to hear the difference.

The harmonic series produces notes with frequencies [imath]F \cdot n \cdot 2^m[/imath], for [imath]n[/imath] reasonably small (usually less than 16) and [imath]m[/imath] any integer. Most of the "half steps" here are totally wonky. No one uses the harmonic series to tune their instruments, for exactly this reason. Half steps are not defined by the harmonic series.

The harmonic series and Pythagorean tuning coincide sometimes (for example, both contain notes with frequencies of [imath]1.5F[/imath]), but these are exceptions. For the most part, they are separate concepts.

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### Re: Music. How and why?

gmalivuk wrote:
Several notes in a true harmonic series will be significantly lower in pitch than what they would be if you applied equal temperament.
Which is why no one uses the harmonic series for tuning all the notes of an instrument.

Musicians playing instruments amenable to pitch bending do often adjust pitches on the fly, though. I can't count the number of times I've been told to adjust 5ths and 3rds of a chord to be closer to the harmonic pitches to make them sound better, and many people do this instinctively.
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gmalivuk
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### Re: Music. How and why?

Major thirds I'll buy, because the harmonic 5:4 ratio you'll get on, for example, a brass instrument is 14 cents off from the equal temperament ratio, and that's audible. But there's only a 2 cent difference between the equal-tempered 5th and the 3:2 5th, and I don't believe that's audible, unless you're playing very pure tones simultaneously that are off by that much.
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polymer
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### Re: Music. How and why?

how equal temperament ruined harmony(And why you should care) by Ross W. Duffin, Is a fun read for people interested in tuning. His argument basically builds off of why you should hate the major third with a fiery passion and develops into why equal temperament misrepresents classical music. Honestly the effects the guy discusses felt really subtle when I tried to experiment with them, but it was still interesting and full of good information. Can't say I completely agree though, major thirds really don't sound that bad...

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### Re: Music. How and why?

gmalivuk wrote:Major thirds I'll buy, because the harmonic 5:4 ratio you'll get on, for example, a brass instrument is 14 cents off from the equal temperament ratio, and that's audible. But there's only a 2 cent difference between the equal-tempered 5th and the 3:2 5th, and I don't believe that's audible, unless you're playing very pure tones simultaneously that are off by that much.

It's entirely possible this is an illusion or due to a different effect, but I've definitely noticed that it *sounds* better if I (raise I think) the 5th of a chord by a little. This could be because the notes I was testing it on were inherently out of tune on my instrument, but a lot of people believe this is a general effect. That said, there's an awful lot of misinformation in the music world.

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One of my high school band directors was aware that the speed of sound not being really really fast caused phasing. He also believed that low pitches traveled slower. To solve this problem, he told the low instruments to play louder.
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achan1058
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### Re: Music. How and why?

Meteorswarm wrote:It's entirely possible this is an illusion or due to a different effect, but I've definitely noticed that it *sounds* better if I (raise I think) the 5th of a chord by a little. This could be because the notes I was testing it on were inherently out of tune on my instrument, but a lot of people believe this is a general effect. That said, there's an awful lot of misinformation in the music world.
It shouldn't be hard to do a blind testing to see which one sounds better. You can use software to generate the pitches at precise frequency, no? Then just use a blind testing software to randomize and have you pick.

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### Re: Music. How and why?

Meteorswarm wrote:It's entirely possible this is an illusion or due to a different effect, but I've definitely noticed that it *sounds* better if I (raise I think) the 5th of a chord by a little.
It's either lower or due to a different effect, because the equal temperament 5th is 2 cents higher than the "perfect" 3:2.

He also believed that low pitches traveled slower. To solve this problem, he told the low instruments to play louder.
Well quite apart from speed, lower sounds do register as quieter to our ears, so the advice was still...sound.
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### Re: Music. How and why?

gmalivuk wrote:
He also believed that low pitches traveled slower. To solve this problem, he told the low instruments to play louder.
Well quite apart from speed, lower sounds do register as quieter to our ears, so the advice was still...sound.

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### Re: Music. How and why?

gmalivuk wrote:Well quite apart from speed, lower sounds do register as quieter to our ears, so the advice was still...sound.

Yeah, it was correct, and it was correct in terms of balance, but it's still wrong because it was using an incorrect model for why, just like thinking the sun goes around the earth can give you some good results, but it's still wrong.
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### Re: Music. How and why?

Moose Hole wrote:There is a class of music that is not taken very seriously, discordant music, which intentionally is discordant. Obviously it sounds bad to people, at first, but I'm a little interested in figuring out if I could get used to it, or anyone else could, enough to actually like it.

I think you can. At least, some people genuinely seem to enjoy full on "dissonant" pieces that use every chromatic note with equal frequency ("twelve tone system") or fill up with quarter tones or stuff like that.

The trick is probably to ease into it, which can sort of be done by experimenting with new compositions in chronological order, as the acceptance of increasing "dissonance" over time has been part of the story of Western music. Start with the "Romantic" period and then continue onward to try and push yourself into further dissonance / find out where your breaking point is?

Moose Hole
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### Re: Music. How and why?

Yeah, I pointed Pandora to Natura Renovatur the other day and it's starting to grow on me. Normal music hasn't started sounding like crap either.

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### Re: Music. How and why?

An important aspect of music comes mainly from the listener's thoughts. For some unknown reason, you expect certain patterns to end certain ways. When they do, that satisfies you. When they don't, it builds up tension that is released at the end (not always, of course). If you listen to a piece that only uses the following, for example:
• A base note
• A major third
• A fourth
• A major seventh,
Then it will be confusing because the "key" has to be the base note, but the expected tonic can be any of them.
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