Octaves

Phil_aka_Pip

We think we know what an octave is. It's like going from the open string to 12 frets up that string, and you get the same note name, right? But the 12 frets and the 8 note names are only consequences of the way in which we divided up something else. The something else is the physical phenomenon of our sensing the "same note" when we double or halve the frequency of a note. I looked up the word "diapason" in connection with something else that I was reading, and found that one of its meanings was that "same note" thing when we double or halve the frequency of a note (http://en.wikipedia.org/wiki/Diapason_(interval)).

Its funny, but the concept is so fundamental ('scuse pun) yet we don't have a commonly used name for it. Even physicists, electronics engineers etc talk about slopes of "so many dB per octave" and they're not interested in 8 notes or 12 frets, only the way their function changes with frequency.

As the word diapason also has other uses maybe we shouldn't start using it in this context, but octave surely is irrelevant if your, er, "octave" is split into 5 notes, or you are playing a sitar with 24 frets between the nut and halfway along the speaking length of the string.

We need another word. Suggestions?

viz

We say octave because we use heptatonic scales in western music. Presumably Indian people say 19-ave or something.

midiglitch

There are proper terms for these things.
In physics they are harmonic partials and the octave is the 1st harmonic / 2nd overtone or 2nd harmonic.

As viz says the word octave arises from the arbitrary (but mathematically quite logical and useful) way we choose to subdivide the naturally occurring "whole".

octatonic

midiglitch said:

There are proper terms for these things.
In physics they are harmonic partials and the octave is the 1st harmonic / 2nd overtone or 2nd harmonic.

When I studied acoustics we were taught that the 1st harmonic is the fundamental and the octave was the 1st overtone/2nd harmonic.

Science of Sound (Rossing, Wheeler, Moore) is quite specific on this.

Phil_aka_Pip

I take it we all know why it's called an "octave", but can we forget the 8 note names & 12 frets, please, and get to the problem of not having a name for what you get when you halve or double frequency, which is not related to a particular culture's way of dividing up that space? 

viz

The thing about the 12 notes system (and the 19 note system) is that you do get very good approximations for the halves, thirds and 5ths. So it works with not too much dissonance.

octatonic

Phil_aka_Pip said:

I take it we all know why it's called an "octave", but can we forget the 8 note names & 12 frets, please, and get to the problem of not having a name for what you get when you halve or double frequency, which is not related to a particular culture's way of dividing up that space? 

Why should we?

Our entire system of music is based on the major scale- it makes sense that it is called an octave.

Phil_aka_Pip

octatonic said:

Phil_aka_Pip said:

I take it we all know why it's called an "octave", but can we forget the 8 note names & 12 frets, please, and get to the problem of not having a name for what you get when you halve or double frequency, which is not related to a particular culture's way of dividing up that space? 

Why should we?

Our entire system of music is based on the major scale- it makes sense that it is called an octave.

To start with it doesn't help, in fact it brings in issues you don't want to discuss (yet), when you're trying to explain the physical properties of a guitar to someone who's trying top get a start in music theory. It makes no sense to lay down a groundwork of scales etc without first defining the physical aspects because all they'll do is ask why you have 8 notes or 12 frets and you get into the circular argument of 8 notes makes an octave, oh, and by the way we divide the octave into 8 notes. Whereas if you start with the physical properties of string length and dividing the speaking length up, noticing that there are special points on the string where you perceive the "same" note, you can then start talking about how you divide up the difference between those pitches into scales.

Secondly it is only our western european system that divides the, er, octave into 8 notes.

   

octatonic

I think you've overthinking it, but call it anything you like.

EricTheWeary

IIRC when I read The Music Instinct the octave is pretty much the only thing common to all forms of music (although clearly called different names) ie no culture has failed to notice it ( unlike say the relationship between root and fifth).
I am sure there are other musical terms that are traditional rather than accurate but I think it would be a significant uphill battle to replace the word octave in common usage.

digitalscream

Question: do you get hung up on the word for "potato" because every other culture has a different word for it, each with its own etymology? The French, for example, call it the "apple from the ground", because that's just how their culture's approach led them to describe it.

Our culture calls the interval representing a doubling/halving of frequency an "octave" because that's how our approach led us to describe it.

Doesn't need to be any more complicated than that.

Phil_aka_Pip

I think that justifying the usage of a word by using the French as an example is a bit much! It may come from the ground but it clearly isn't an apple. French is such an arse-about-tit language anyway, I'd use is a the prime example of how NOT to describe things.

Yes I KNOW Our culture calls the interval representing a doubling/halving of frequency an "octave" because that's how our approach led us to describe it. THAT IS NOT THE POINT!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

All I asked for was a culturally independent word to refer to a physical phenomenon. Why is that asking too much???????

ChrisMusic

I don't have an answer, but I do feel your pain, well frustration anyway.

It is a very valid question too.

And you are right about the circular argument in using octave as an explanation, it is an inadequate word for this.

I thought you might appreciate a bit of support out here on the frontier.

hmmm, be back when I've given it some thought (which is in short supply right now)  

octatonic

Phil_aka_Pip said:

I think that justifying the usage of a word by using the French as an example is a bit much! It may come from the ground but it clearly isn't an apple. French is such an arse-about-tit language anyway, I'd use is a the prime example of how NOT to describe things.

Yes I KNOW Our culture calls the interval representing a doubling/halving of frequency an "octave" because that's how our approach led us to describe it. THAT IS NOT THE POINT!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

All I asked for was a culturally independent word to refer to a physical phenomenon. Why is that asking too much???????

Because, that is how language works when it intersects with culture.

It was first used in the 14th Century and people used it because it made sense in the communities that it was used in.

It also means ' an 8-day period of observances beginning with a festival day', 'the first 8 lines in an Italian sonnet' and various other things.

The entomology is from the medieval Latin 'octavo'.

Maybe the best reason is 'because it does'.

Phil_aka_Pip

@ChrisMusic thanks mate. I doubt that any of us are going to come up with an answer that "rocks the establishment", but I ward you a wisdom for seeing the validity of the question!

ChrisMusic

stickyfiddle

We do have a name for this phenomenon. They're referred to in physics as Normal Modes, irrespective of music or how our ears hear sound.

So in guitarspeak the open string is the first mode, the 12th fret harmonic creates the 2nd mode, the 7th fret harm gives the 3rd mode, and the 5th fret the fourth mode... All the even-numbered modes are heard by our ears as octaves above that original fundamental note.

The points on the string that correspond with those fret points are called nodes.

Phil_aka_Pip

@stickyfiddle I didn't know this (bet a lot of others didn't either). I was only aware of modes as scales starting from different points. Now I know another use of the word mode, and can google for it. Fanx. You get a wisdom too!

stickyfiddle

No probs!

Physics has an answer for everything

daveww

Does this help you guys   I remember watching this at school.

http://www.youtube.com/watch?v=iEVGQKwKeCc

@phil_aka_pip it's a secret  

Phil_aka_Pip

@daveww I'll watch that when The Early Music Show is done (20 mins)!