General Question

Harp's avatar

What's so special about octaves?

Asked by Harp (19166points) July 31st, 2008

Really a question about tonal perception:
Even someone without musical training will recognize some kinship between two notes an octave apart. They’re not the same pitch, obviously, but they are, in some intuitive sense, “the same note”. Our conventions for naming notes recognizes this, but I don’t think our perception of this “same note but different pitch” derives from our notation conventions.

So I can’t help wondering why this octave interval should be so easily and naturally recognizable to our ear. Why could most 10 year-olds effortlessly sing an octave interval, but not a fifth or third? After all, we hear fifths and thirds as much as we hear octaves in Western music.

Hope this makes sense

Observing members: 0 Composing members: 0

19 Answers

sndfreQ's avatar

Perhaps it’s because the octave is the first interval in the overtone (natural harmonic) series. Also the resonance between tones that are an octave apart are due to the mathematical (ratio) relationship in terms of frequency; the distance of an octave is exactly a ratio of 2:1 or double the root frequency, regardless of tuning system, probably explaining why octaves (the aural interval) appear in non-western tuning systems. I’ve always found the term to be a bit archaic, but the concept of the ratio and frequency relationship a universal one.

iwamoto's avatar

good question, but i don’t really have an answer, in some way it just…the same…

Harp's avatar

All true, but our hypothetical 10 year-old singing his octave doesn’t have a clue about any of that.

sndfreQ's avatar

As a youngster just starting out in instrumental music and vocal training, many of my teachers told me I was one of the very few with “perfect pitch.”. As if it were a gift of some sort; to me it was just a nebulous concept, but what I really felt was that my “memory” of tones was spot-on; as I learned what notes were and their notation (and eventually intervals, chords, etc.), I came to realize that all of this is really dependent on pitch memory, and I believe that at it’s fundament, the natural resonance of the octave “rings true” as the most recognizable pitch class relationship, if not the most frequently recurring in nature.

Harp's avatar

I’m green with envy of your perfect pitch

marinelife's avatar

I found this study using rhesus monkeys interesting. It really speaks to the universal nature of the octave.

“They did show complete octave generalization to childhood songs (e.g., “Happy Birthday”) and tonal melodies (from a tonality algorithm). Octave generalization was equally strong for 2-octave transpositions but not for 0.5— or 1.5-octave transpositions of childhood songs. These results combine to show that tonal melodies form musical gestalts for monkeys, as they do for humans, and retain their identity when transposed with whole octaves so that chroma (key) is preserved. This conclusion implicates similar transduction, storage, processing, and relational memory of musical passages in monkeys and humans and has implications for nature-mLrmre origins of music perception.”

mvgolden's avatar

Harp, you just knew I would chime in. I’m not much of a music theorist but I will give the physics a shot.

When you break down notes sung or played on an instrument that are an octave apart into it’s component pure tones (ie take the FFT) you will see that many of the overtones line up.

For example an A at 440 Hz has its fundamental at 440Hz and overtones at 880, 1320, 1760,..... The A the next octave up has it’s fundamental at 880Hz and overtones at 1760, 2640….. We see that many of the overtones occur at the same frequency.

Our ear has lots and lots of hairs on our Cochlea. Each hair responses to different frequencies. So many of the same cochlea hairs are vibrating for notes that are at different octaves. My guess is that we can sense that and our brain can sort it all out.

I don’t think that happens for fifths or thirds.

Lightlyseared's avatar

They sound nice.

sndfreQ's avatar

@Harp-believe me when I say this, perfect pitch is both a “blessing” and a “curse.”. On the one hand great for keeping yourself / your instrument in tune, horrible because you get to hear the rest of the world be out of pitch the rest of the time.

It reminds me of the twisted wishes “question” that pops up here once in awhile…

Harp's avatar

I was fascinated to read recently that, to many people with perfect pitch, pieces of music are so strongly associated with their keys that hearing a piece transposed to a different key is jarring, as if it that altered its very identity. For us relative pitchers, we’d never even know the difference.

sndfreQ's avatar

Yes absolutely true-to the point that it nearly drives me to madness to hear even the slightest de-tuning, i.e., when a recording is played on vinyl or tape and the player is calibrated 0.1% faster/slower, or when radio stations intentionally speed up a record on the CD player or computer to squeeze out a couple of seconds more for commercials.

Harp's avatar

I also read that some perfect pitchers experience “pitch creep” as they age, so that their mental pitch drifts away from absolute pitch, but often not uniformly across the sound spectrum. So you may have that to look forward to.

Knotmyday's avatar

My take is that it’s just easier to go from Do to Do avoiding harmonic dissonance. Is “dissonance” the correct term? Maybe “chording?” Same for enharmonics etc. I bow to the technical expertise of sndfreQ, and his “curse.”

cwilbur's avatar

The 10-year-olds can sing the octave because it seems like “the same note, only higher.” This is because the octave relationship is the closest relationship that two notes can have; the first overtone is the octave. The 10-year-olds aren’t aware of this, but it’s what makes them seem so closely related.

wundayatta's avatar

I like mygolden’s explanation. Certainly we recognize the overtone series in the way he suggested. Notes at each octave will have the same overtone series, so they sound the same except for having a fundamental that is different. If you push down the damper pedal on a piano, and hit a key, each key in the octaves above will resonate most strongly, though the thirds and fifths will also vibrate in sympathy.

On any instrument, when you cut the length of the instrument in half, and play it, you will find the pitch goes up an octave. Place a finger in the middle of a guitar string, and you hear the octave sounding (this is because you are damping the vibration of the entire string, yet allowing the two halves to vibrate freely, but at an octave up. You can also get fifths, thirds and double octaves to sound by putting your finger in the right place.

On any brass instrument, you can play the overtone series by using your lips to emphasize certain overtones. On the trumpet you get the first octave above the fundamental (I’m not sure why), then a fifth up, a fourth above that, a third above that, and so on.

However, even if there are no overtones; even if a synthesizer plays a pure pitch, we recognize the octaves easily. I’m sure it has something to do with the way these frequencies stimulate the cochlea. Octaves must all stimulate the same cochlea, so we perceive them as the same note, except we also recognize they are at a higher or lower pitch. In any case, it’s easy to hear which tones match other tones in the harmonic progression.

Or is it? Is there such a thing as being tone deaf? Many people will tell you they can’t carry a tune. Does this mean they are innately unable to identify separate pitches?

Well, no. The ability to distinguish pitches, and even perfect pitch are learned, just as language is learned. If you aren’t trained, you won’t learn it; and if you are, you will attain perfect pitch. People with tonal languages, such as Chinese, have a much higher proportion of those with perfect pitch, because pitch is necessary to understanding the language. My son, when he first started piano, knew the notes perfectly, but since we haven’t worked on it for a while, he may not have it any more.

Sndfreq started learning music as a youngster (but how young?) and his teacher identified him as having perfect pitch, so they probably worked on it, practicing formally or informally, and that’s what made him able to retain his memory of pitches. I’ll bet there was a lot of music in his house even before he started. Maybe his parents were musicians, too. I could be wrong in all these predictions, but it would be consistent with the history if I’m right.

Of course, the really interesting thing about music is what it does to your brain, and how it can alter your consciousness. Now there’s a question!

sndfreQ's avatar

Nice explanation daloon! I started playing instruments at age 4 (piano), singing in children’s choirs at age 9, viola/violin at age 10, percussion at age 12, etc.

I think your point about Chinese and more “tonal” languages is really an interesting one, as in my youth, I observed that many students of asian ethnicity/descent were in my music classes. Suzuki method, for violin and stringed instruments, relies on memorization versus reading printed sheet music. I can see that much of this was part of my early development in music studies.

wundayatta's avatar

My children both started Suzuki piano at age 4. My daughter switched to a conventional teacher a couple of years later. She is now switching to voice. My son is still with Suzuki. I believe musical training trains you in so many more ways than just music. However, it is a lot of work; more perhaps than American parents are willing to put in. This is an issue between me and my wife, now, as my son is about to enter 3rd grade, and homework will start.

28lorelei's avatar

sndfreQ just a tip 4 u:
train yourself 2 be able 2 play on a transposed keyboard (if u play piano)
on any electric keyboard there is a “transpose” function. At least it’s helped me be able to listen to transpose music and to think in other keys than the one the piece is written in.
Hope this helps:)

28lorelei's avatar

also, what is so special about octaves: pitch chroma is the same. Pitch chroma is basically “C-ness” or “D-ness,” and is very subtle. What you are hearing is the difference from one pitch to another.

Answer this question




to answer.

This question is in the General Section. Responses must be helpful and on-topic.

Your answer will be saved while you login or join.

Have a question? Ask Fluther!

What do you know more about?
Knowledge Networking @ Fluther