String quartets -- when they're unamplified, of course -- are also a study in sonic complexity. The violin family can produce amazing ranges of overtones. In a quartet, you can
really hear that stuff. (Problem with seeing someone like Kronos Quartet is that they may be amplified in a big venue. Of course, that makes their version of "Purple Haze" a little more impactful. :D )
And, of course, chamber orchestras offer a good in-between.
But it's not only violins that produce amazing overtones. I do not believe I have ever heard a recording that has fully captured the amazing sound of a horn section playing a complex harmony... in fact, it was
that sound that started me thinking about all this back when I was in recording school at a local community college. We'd often help out or just
hang at our school concert hall during set up and sound checks, even those of us not taking sound reinforcement classes and so we'd hear the sound of the horn sections with and without miking and amplification... And on those occasions when I recorded horn sections, I was always a little disappointed by how much was lost. But when I'd check my recordings at home, I never heard precisely what you hear in person, listening to a section playing some tart harmony, unamplified.
Orchestral music isn't everyone's cup of tea, of course. And the economics and audience situation is such that many orchestras cannot be as adventurous as they might like (so you get more chestnuts, because that's what a lot of folks like -- my local symphony orchestra has learned to tread lightly in the twentieth century for that reason but they do sneak in newer work) but there's always something to watch or listen for.
[Personal gripe: modern works that require amplification for the soloist in concertos or other works built around one or two soloists)... it's seemed to me for a long time that if a concerto is
written properly, and the concert hall is designed properly, that the soloist shouldn't need to be amplified, for the most part. The exception is often spanish/classical guitars, which are often amplified these days. And -- of course -- if you go to a big outdoor venue like the Hollywood Bowl, expect to hear amplification. But, you know, listening to a great orchestra under the stars is its own compensation.
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