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  Spectralism  MartinY at 09:38 on 27 January 2010
 

Zak's questions in the complexity forum have raised questions which are essentially about spectralism in music so perhaps we need a different thread....

Does anyone remember the engineer who did the opposite of what is normally done and re-engineered handbells to produce a much purer harmonic series than the huge anharmonicities in standard handbells. I remember hearing a piece on TV played by the harmonic bells which were much nearer cylindrical than normal bells but was suprised I did not hear a dramatic difference other than that they were sweeter. I suppose a lot of the perception of bell sound comes from the moment of clanger impact not the resonance afterwards.

  Re: Spectralism  Zak at 23:02 on 27 January 2010
 

Hi,
I searched "spectralism" and found this article:

http://entertainment.timesonline.co.uk/tol/arts_and_entertainment/music/article4914202.eced

(I don't quite agree with calling it the "future of music", but I suppose that's a subject for another forum.)

The Wikipedia article on Spectral music is also interesting.

I think this relates somewhat to the issue of computer (or computer assisted) composition, something I have doubts about. The idea of using sound spectra in composing is intriguing, however. And here I thought the whole idea was probably idiotic!

  Re: Spectralism  MartinY at 08:48 on 28 January 2010
 

Interesting but probably useless -

a few years ago, in Chemistry, I was interested in models of molecules where different molecules have identical spectra, (molecular spectra are much higher in energy than sound so you can't hear molecules but you could Doppler shift them down into the sound region if you really wanted to..... You could then have the benzene scale, the aspirin scale, (the alcohol scale would be rather gapped cos the electrons are held so tightly), etc....).

The same applies to 2 dimensional membranes, i.e. drum heads. I have an article somewhere about this which gives many examples of different shapes of drum head which give the same spectrum and explains how mathematicians can classify and interpret this. So what we have is that shape defines spectrum but the spectrum does not uniquely define shape. Unfortunately I do not know if this is of any use whatsoever except to defence lawyers if you could prove that mass-spec to HPLC does not identify a unique molecule. However that situation is so much more complicated that I think those spectra are unique unless you have a truely infinite number of molecules.

  Re: Spectralism  MartinY at 08:59 on 28 January 2010
 

This really is a question generated by Oscar Bettison's multi piano piece in the blogs, but I thought as it might lead to some comments in the forum so it should be here.

When writing for multiple pianos is it common practice for some pianos to play ghost parts where they depress keys without making any noise but lifting the dampers off so that the resonances of the playing instruments are changed? If it is how effective is it?

  Re: Spectralism  Zak at 23:05 on 28 January 2010
 

Those are both interesting ideas. (I like the idea of an aspirin scale--wonder if it would be good for headaches and fevers? ) Ghost tones like you describe would also be useful on only one piano, as if you hit the keys on either side it will make the strings of the depressed key vibrate slightly, if the dampers are up. I have only seen the technique of "ghost tones" used once, though, in Brahms' exercises for the piano, and there it is not so much for resonance as for dexterity.

  Re: Spectralism  Zak at 23:37 on 28 January 2010
 

An idea I had that may relate more to complexity, but I'll put it here anyway: Is complexity in music really preferable to simplicity? But then one must ask: What is simplicity? Is there even such a thing as simplicity in music, given that the physical properties of sound itself (i.e., the overtone series, the ratios between sounding bodies.) are so complex? I haven't yet been able to give this question a satisfactory Yes or No answer, which implies to me that there isn't a yes or no answer to this question. Any thoughts?

  Re: Spectralism  scott_good at 00:42 on 29 January 2010
 

"When writing for multiple pianos is it common practice for some pianos to play ghost parts where they depress keys without making any noise but lifting the dampers off so that the resonances of the playing instruments are changed? If it is how effective is it?"

would be very hard to hear (i think...), but, if amplified, might have an interesting resonance effect. This, I have done, but with brass instruments playing - they tend to get the vibrating going strong! I used surround sound amplification, and it built up resonance chorals in the piano - was very cool and I didn't tell any one ahead, so, quite a "mysterious" experience for the audience.

"I like the idea of an aspirin scale--wonder if it would be good for headaches and fevers?"

Yes. At causing them! (ha ha)

"Ghost tones like you describe would also be useful on only one piano, as if you hit the keys on either side it will make the strings of the depressed key vibrate slightly, if the dampers are up."

I think it might work even better simply by lifting dampers off notes in the lowest register - these are the strings that will really get going. Try it. Hold the low B down, and then play some staccato high B's loud and short up high - rings quite nicely.

"An idea I had that may relate more to complexity, but I'll put it here anyway: Is complexity in music really preferable to simplicity?"

Maybe sometimes.

"But then one must ask: What is simplicity? Is there even such a thing as simplicity in music, given that the physical properties of sound itself (i.e., the overtone series, the ratios between sounding bodies.) are so complex? I haven't yet been able to give this question a satisfactory Yes or No answer, which implies to me that there isn't a yes or no answer to this question. Any thoughts?"

Good thoughts. I agree. Even just the issues of intonation brings up a world of possibility and complexity.

But, it still can be fun/interesting to discuss - especially when looking at certain parameters, such as simply the notes on the staff which is, after all, the game of the composer.

Also, the simplicity vs. complexity issue can be looked at as how music is perceived, not what it actually is. Like catching a ball, something most would consider simple - but not to a child, and also difficult for a computer! But then issues of culture and exposure/training become the focus. For instance, a Bach fugue can sound like "a thing" - then, it is relatively simple - an undulating texture shaped by rhythm and harmony. Or, to a more trained or exposed ear, it can sound like "many things" at the same time - it is counterpoint, and more complex.

Does that make sense?

  Re: Spectralism  Zak at 01:44 on 29 January 2010
 

Yes, that makes sense.

And you're right that the simplicity/complexity issue (is it really simplicity vs. complexity?) is interesting to discuss, even if we can't define those terms in a way that everyone will agree upon.

I suppose that brass and other pianos (or other strings on the same piano) would be the only things that can set the strings of a piano vibrating (well, musically speaking, that is), but it is likely that you're right about it being hard to hear without amplification.

And, what about a plutonium scale?

<Added>

(Better hope that one doesn't get into the wrong hands.)

  Re: Spectralism  MartinY at 08:22 on 29 January 2010
 

Plutonium scale...... Atomic spectra are a lot like a unique (to the atom) version of the harmonic series but because atoms are 3-dimensional there are what we call degeneracies where there are several harmonics with the same frequency. As you get bigger atoms there are more of these degeneracies. The shapes of the atomic orbitals are very interesting, see:

http://winter.group.shef.ac.uk/orbitron/AOs/6p/index.html

By the time you get to plutonium the 1s and 2s electrons are whizzing around so fast that relativity becomes important. I will have something more to say about that but in the context of A followed by B not being the same as B followed by A, (why has that got anything to do with Einstein and Dirac???).

  Re: Spectralism  Zak at 00:30 on 30 January 2010
 

Very interesting, though I was just joking. I suppose there could be musical applications here, though. But what would that be? Where would you use something like an aspirin scale (unless it was in a piece describing aspirin--which probably would be good at causing headaches)?

Anyway, I tried out several things involving "ghost tones" on the piano; the most resonant technique was repeatedly playing a tone while holding down the keys of the overtones of that tone to the sixth partial. That produced a nice, resonant ringing that was quite audible and almost seemed to change the timbre a bit.

  Re: Spectralism  MartinY at 07:40 on 30 January 2010
 

Yes - we are all joking and I do not think there are any real applications other than, say to extract a motif from a molecular spectrum and incorporate it for some reason, like being given a fugue subject from someone else, or a representation of the cannibol molecule in a set of variations on a theme by Christian Cannabich or some such thing......

But there are relatively useless questions of a philosophical nature here. Those atomic orbital pictures are actually the same shape as the partials inside a spherical ocarina. (Though the ocarina sound is nearly all fundamental, it does not want to excite a partial with 28 nodes in it very readily.) (Mini ocarinas are ideal for audiance participation pieces... They probably can be produced much cheaper than recorders.)

A bit more useless? but philosophical stuff, which does have a use..... A tiny harmonic oscillator has a spectrum which is a ladder of equally spaced frequencies, so equal temperament does exist in nature. It is either the whole tone scale or the chromatic scale.

A tiny rotor has a spectrum which is close at the bottom but gets wider apart as you go up in frequency, (the energy goes as J(J+1) where J is the excitation number. So it gets harder to spin more as it goes faster. This is the reverse of most spectra which get closer as you go up in energy. Just a thought... We do not have much common practice music where the bass moves by semitones and the flutes move in 5ths.



  Re: Spectralism  Zak at 23:34 on 30 January 2010
 

Yes, there are many philosophical (perhaps even religious) questions here.

"Atomic spectra are a lot like a unique (to the atom) version of the harmonic series..."

Something perhaps like Pythagoras' "music of the spheres"?

Drawing motivic material from atomic/molecular spectra could be useful if approached with caution. It would all depend upon how it sounded.

"A tiny rotor has a spectrum which is close at the bottom but gets wider apart as you go up in frequency[.]...This is the reverse of most spectra which get closer as you go up in energy."

Sort of like an upside-down version of the harmonic series?

<Added>

One hundred years in the future...

Teacher: Class, today we are going to study Zak A. Hunter's Variations on H2O. (And Handel thought he composed Water Music! Oohoo hoo hoo!)

<Added>

Seriously, though, something to think about. If the sonic result is useable.

  Re: Spectralism  MartinY at 10:56 on 25 March 2010
 

Have people seen the relatively recent research which shows that prairie dogs are spectralists? They have a language where, for example the word for badger and the word for eagle have the same articulation but a different overtone spectrum. Prairie dogs in zoos loose much of their facility in language in a generation or so because there are no predators in zoos. Spectralist pieces which make extensive use of changing overtones might not work for everybody because there is clearly an element of knowing what to listen for........ (can it be a private language?)

The importance of articulation in the perception of instrumental colour... another area where there is published research worth looking at. I think the idea is that the articulation is at least as important as the overtone spectrum.

I was reading an article the other day about electronic paper. You may know that the way colour is created in a liquid crystal display, an high quality magazine print and a butterfly's wings is entirely different. I was wondering whether any of this can be transferred into the ideas for generating a piece based on instrumental colour in new ways. The analogy of colour in music is more like harmony, (different frequencies), though of course the interaction of harmony, instrumental colour and articulation is potentially very important. (There are examples of chords which sound terribly out of tune in one instrumentation, even though they are not, and quite different in other orchestrations. Conductors have their own lists of bete noir chords in the repertoire. 6/4 like chords in late romantic orchestration can be particularly dodgy.)

I hope to get time to do some experiments on these ideas using a large guitar ensemble on the one hand and a large recorder (quite pure tones) ensemble on the other.

  Re: Spectralism  MartinY at 08:26 on 18 April 2010
 

When I used to teach Maths for Scientists I still found people who cound not see why one needed negative numbers! How do you undo adding one to seven if do not have -1???? but anyway, one can readily appreciate that complex numbers are going to meet even more resistance and even highly educated people think there are a ridiculous abstraction which has no place in a rational number scheme. However they are absolutely necessary for a complete number system though I do not think I could prove that in the small space here......

When we talked about A.B not being the same as B.A earlier and I said that scientists like them to be the same as the mathematics is much more tractable, I forgot to say that when A.B is not equal to B.A it is absolutely necessary to use complex numbers in the mathematical solution of the problem. So there is some fundamental link between time / sequence and complex numbers.

Complex numbers are needed to describe complicated geometries and frequencies, light (sound) so it is probably good that spectralists get familiar with some level of complex analysis. Of course students have told me well you can always separate complex numbers into two real numbers like we often do in the computer so why do we need them? but if you do that to get the right answer you need different rules for the imaginary part so you are back needing comnplex numbers by the back door.

Relativity needs complex numbers, see

http://bnreview.barnesandnoble.com/t5/The-Thinking-Read/The-Strangest-Man-The-Hidden-Life-of-Paul-Dirac-Mystic-of-the/ba-p/1243

for a a relevent artcle about the work of Dirac, whose equation leads to a wavefunction which is eight times bigger than a standard wave function and gives the same answers at must greater expense for many properties. However it gives the right answers for very heavy things like the uranium atom and very fast electrons in small molecules where the standard equations go wrong.....

Anyway I do not know how complex numbers will help spectralists but they certainly help the people how design the machines that they use! These numbers are often taught in a very superficial way in about 1/2 a hour saying something like, it is easy, 2i x 3i is minus 6 and the quantum momentum is i hcrossed d by dt and that is all you need to know, instead of doing the hours of problems and examples which are necessary for mere mortals to get to grips with it... No wonder even many scientists think it is a load of useless rubbish.

(Question, is it relativity which makes minim crotchet crotchet turn from a funeral march to the William Tell Overture when it goes faster?)