Some odd instruments and strange adaptations of standard ones have been sprouting amid the familiar strings and brass of classical music concerts.

To create the required resonance for a Boulez sonata, for example, the pianist Marc Ponthus connected two grand pianos with a piece of wood, allowing him to work the sustain pedal of the second from his seat at the first.

And the flutist and composer Robert Dick played works he wrote for a flute outfitted with what he calls a glissando headjoint, an extension of the mouthpiece that lets him shape his instrument’s lines by sliding from note to note .

The Partch Ensemble, named for the quirky composer and instrument inventor Harry Partch, performed “There Isn’t Time,” a new work by Victoria Bond for instruments that are outlandish blends of Asian and Western materials and designs. Partch’s instruments use their own tuning systems, with as many as 43 notes (rather than the standard 12) in an octave.

People who worry that classical music is a museum culture normally focus on the repertory, or, more specifically, on players and listeners who prefer the 19th-century canon in classical music.

But the same preservationist impulse that keeps the standard repertory in the spotlight controls instrumentation too. Minor technical improvements may be tolerable here and there, but anything that changes the essential nature, sound or look of an instrument will seem to them an assault on tradition. This kind of arrested development is historically peculiar.

After all, most of Western musical history, from medieval times until the mid-19th century, was also a period of virtually nonstop instrument evolution. Composers responded to the latest developments by writing works that took advantage of the new instruments’ abilities. With the introduction of the fortepiano, for example, Haydn was able to write smooth, singing lines that could have been barely hinted at on the harpsichord.

And Beethoven’s late sonatas require a heftier instrument than the kind Haydn first encountered. Today’s composers have a difficult choice. If they want to be heard by the traditional classical music audience - that is, if they want their works to be regarded as part of the historic mainstream - they have to write for the 19th-century instruments that most ensembles play. But some composers have rebelled against the tyranny of standard instruments.

Partch, for one, began building his own instruments in 1930, and added steadily to his collection through the late 1960s. And though Minimalist and post-Minimalist composers now write plentifully for mainstream orchestra and chamber ensembles, several were outliers at first, starting their own bands with distinctive aural thumbprints.

The heart of Steve Reich’s group was percussion, with voices, strings and other instruments added as required. Philip Glass’s early ensemble was built around winds, voices and keyboards. But Mr. Glass, in those early days, did not want just any keyboards: he was fond of the reedy sound of the Farfisa organ.

These days Mr. Glass’s group plays on pricier, more high-tech instruments that can approximate the Farfisa, along with countless sounds the Farfisa could never produce. If you’re a Glass purist ? or a periodinstrument fanatic, modern division - the new sound is a compromise. But Mr. Glass has never cared to be a prisoner of historical detail.

Since then, composers have led ensembles of all kinds, and the most common - Missy Mazzoli’s Victoire, or some of the groups led by Du Yun, for example ? are classical-rock or classical-jazz hybrids. And some have oddball lead instruments.

The composer Ben Neill, for example, plays what he calls the mutantrumpet - a trumpet with three bells (instead of one), six valves (instead of three), a trombone slide and an electronic interface that can turn it into a synthesizer controller.

Are any of these instruments likely to become standard? It hardly matters, really. They are here now, being played by, and composed for, musicians who are fascinated with them, and that is enough. But if I were to hazard a guess which of them might have a future, it would have to be Mr. Dick’s flute with a glissando headjoint.

It is, after all, not a complete reworking of the flute - simply an addition that allows Mr. Dick, a virtuoso even on a standard instrument, to create effects otherwise unavailable to him. Besides, I love the back story.

Mr. Dick, though a classical player, is a devoted Jimi Hendrix fan. And having long admired the way Hendrix used the guitar’s whammy bar - a metal lever fastened to the bridge - to bend pitches and control his instrument’s howling feedback, he began thinking about making an equivalent for the flute.

Now all Mr. Dick has to do is write enough music that demands the headjoint, and that flutists will want to play ? and, perhaps more important, persuade lots of his composing colleagues to do the same.


ALLAN KOZINN/ESSAY