Author: mschmidt
Date: 2006-01-23 22:55
Sorry to join this discussion so late.
I think the issue of timbre is quite complex. "Bright" and "dark" are two adjectives commonly used, and I would agree that they hardly do justice to the variety of sounds that can be gotten even from a single player and a single oboe. Yes, they do have to do with partials, with overtones. And dark does correlate with fewer higher overtones. But there are many overtones, and I think that the differences in sounds have to do with the whole distribution of overtones.
Ohsuzan stated that she doesn't know how one would measure the partials--well, it's not that hard, but understanding what one measures is something else! You can find freeware programs on the net that are "spectrum analyzers;" I have downloaded two for my iMac at home (still running System 9) but I'm sure there are some for Windows machines as well. They can take a microphone input and perform a Fast Fourier Transform (FFT) on the waveform and spit out a graphic showing the amplitudes of the various overtones. I've done this, and it's wild. "Wild," as in "what the heck?" There's no simple correlation between "dark" sound and the absence of higher partials, at least not that I can see. This may be due to the relatively low resolution of the frequency "bins" that are necessary for real-time output. (I could do without the real-time output if it meant a better graph of the partials, but the software seems to be all about real-time processing.) The pattern of partials seemed to vary more between different notes on the oboe than they did between the same note played on very different reeds. I couldn't make sense of it.
But this is my current theory, best explained by analogy. There are not so many different olfactory receptors in the nose, and yet we can know thousands of different fragrances. The reason is that there is a combination of different strength signals from different receptors for each fragrance. Both "rose" and "violet" may trigger many of the same sensors, but "rose" may trigger sensor A to a 70% level and sensor B to a 30% level, whereas "violet" may trigger A to a 60% level and sensor B to a 40% level. The brain puts this all together in such a way that "rose" and "violet" can be recognized along with thousands of other fragrances.
Likewise with tones. There are not just "lower partials" and "upper partials;" there are probably quite a few different partials that matter, and they are probably always present in all oboe timbres--otherwise they wouldn't be recognized as oboe timbres! But subtle variations in the proportional strengths of these partials are put together by the brain and associated with players, or moods, or labels like "dark" and "bright." What you imagine to be a dark sound may actually contain higher levels of particular higher partials, in addition to stronger lower partials. So, yes, "bright" and "dark" may be somewhat subjective, but they may also correlate with physically measurable phenomena. And short of a detailed and precise statement of the levels of all the relevant partials, there may be no "objective" way to describe oboe tone.
Let me elaborate still further on that last sentence! There is a scholar at the University of California, San Diego that has shown that people who grew up in areas with different accents hear ambiguous tones differently. By mixing a bunch of frequencies (overtones), she can generate pairs of tones that will be heard differently by different people. How differently? Well, some people would say the first tone was lower than the second; others would say the second tone was lower than the first. If you try this with a whole set of "ambiguous" tones, you can correlate the results with where the person grew up. The brain "classifies" the different overtone combinations differently depending on how, as a young child, it learned to understand the speech of the people in its location. People from the American South hear ambiguous tones differently from people of the American West. About 10 years ago a CD was available of these tones, and you could "test" your hearing of the tones and find out where you came from!
Well, if that is true, then isn't it quite possible that we don't even hear the same thing when we hear oboe tones? That one person's "sweet and round" will be another's "bright and warm?" And just as regional accents may fade from speech in the wake of television and radio, so too musical accents may fade from orchestras.
BUT...it also may be that, as listeners get older, they are less likely to hear all the partials as their hearing becomes less acute, especially at the highest frequencies. If this is the case, it will always be true that "oboists sound more alike now than when I was a young student..."
mike
Mike
Still an Amateur, but not really middle-aged anymore
|
|
The Oboe BBoard
.jpg){kind=small}
