There is nothing worse than getting invited over to the neighbors' house so they can coax their offspring into committing music on you with some unorthodox instrument. That happened to me recently. Accordions, even when played well, are deadly from less than five feet away, and, in any event, almost as bad as a kazoo. My friends' once sow-sized piggy bank has shrunk to an anorexic slice of bacon from months of lessons to get the kid to sound not even as good as that trained seal on TV playing The Bells of Saint Mary's on glass chimes.
Why the accordion, you ask? If you're raising a soloist, why not get him or her a violin or piano or any number of other noble instruments for which the likes of Mozart, Chopin and Beethoven composed great music? True, but on the other hand, if you play an unusual instrument, you may not have much to play, but you won't have much competition, either, and in an age of open admissions, lowered standards and diminishing expectations, what more could one ask for?! As it turns out, however, there is at least one solo piece for "classical" accordion: The Rubàiyat of Omar Khayyàm by Alan Hovhaness, and I imagine if you get really good at it you may get those 15 minutes of fame you're entitled to.
Other oddball instruments? I went to San Carlo once and heard a concerto for alphorn. An alphorn is a long conical instrument resembling the business end of an unbelievably large unicorn. It is played with a mouthpiece, like a trumpet, and the Swiss play it in order to relax the cows in the Alps, a harder job than you might think, since most Swiss cows are nervous wrecks from the incessant beep-beep of all those automatic money machines going off throughout their native land. In any event, the soloist walked out on stage pushing fifteen feet of alphorn in front of him, the far end mounted on a tiny caster which let him roll the thing around the stage. I have no idea how he got it into a taxi to get back to his hotel after the concert.
If you know what a tuba is, you might feel that no one would ever compose a concerto for an instrument which —except for a few florid passages in Wagner— has traditionally been confined to the "Oomp-" part in Bavarian Oomp-Pah bands. Yet, a fine Concerto for Tuba has indeed been written by Ralph Vaughan-Williams. Tuba players now have to practice a lot more than they used to simply because Ralph decided to write a difficult piece of solo music for them. Many tuba players do not like Ralph.
Musical exotica continues with such things as the human whistle. There are a couple of dozen professional whistlers in Los Angeles and they are the ones who do any whistling you may hear on film sound tracks. The main theme from The High and the Mighty with John Wayne was, in fact, a whistle solo. (Nope, the Duke was faking it; he was puckering, all right, but it was overdubbed by a pro.) How about, say, the harmonica? Glad you asked. Yes, if you take up that humble axe, you will, indeed, have more to play than just them low-down dirty-rotten Mississippi Delta blues, oh yeah. There is a concerto for harmonica by the great Brazilian composer Hector Villa-Lobos.
Perhaps the weirdest solo instrument is one which everyone has tried at one time or another: the wine glass! If you wet a finger (preferably your own) and rub it around the rim of the glass, you get a note. (Just keep drinking the wine until you get the note you want!) Now, imagine a spindle turned by a treadle. Along the length of the spindle is mounted a series of different-sized glasses, each one producing a different note. You work the treadle to turn the spindle and glasses; then, you moisten your fingers in the water-basin in front of you and produce the notes you want by touching the proper glasses. That instrument is called a glass harmonica and at least one short work has been composed for it by none other than the Wolfman, himself —Mozart. Wine glasses produce an eerie, other-worldly and not particularly pleasant sound. It drives dogs nuts. Maybe humans, too, since Donizetti uses the instrument in Lucia di Lammermoor in the scene where the heroine goes insane. It is not clear to me whether the plot actually calls for Lucia to go crazy, or whether it's the fault of that guy playing the wine glasses down there in the orchestra pit. Actually, most of the time orchestras can't find a "glassist", so they give the part to the flute. It's not at all the same thing, but Lucia reports feeling much better.
Certainly the worst-sounding contraption ever rumored to make music is the bag-pipes. They were invented by an ancient race of people whose religious rituals involved tormenting asthmatic sheep; the animals' pitiful bleats of despair are accurately reproduced by this instrument. As far as I know, there has been no concerto, sonata, or even a four-measure rest written for bagpipes, but if someone ever composes one I certainly don't want to fail to miss it. Interestingly, there is an opera by Jaomir Wienberger entitled Schwanda, The Bagpipe Player. It was well-received at the premiere in the 1920s, apparently because at no time does Schwanda actually show up on stage and play. This is good.
[Related item on the musical ratchet here.]