They look unassuming, but once they’re plugged into an amplifier, piezo discs become psychedelic microscopes for your ears, completely changing your sense of sonic scale. I taped one to the bottom of a water bottle on a hot afternoon and ran the signal through a reverb pedal; the ice cubes banging around sounded like gongs from distant planets. Rubbing a piezo mic against a felt cowboy hat sent me down a sound-dappled path of contemplation, musing on the subtleties of surface texture and how difficult it would be to play croquet on a felt cowboy hat if you were, say, 10 molecules tall. My dumb guitar never led me to such insights.

Best of all, piezo mics are cheap — probably one of the most affordable technologies for completely transforming your appreciation of our world. You can spend hundreds of dollars on a high-quality contact mic specially designed for the subtle timbres of an orchestral string instrument if that’s what you want. If what you want, however, is to drink some beers, plug in some pedals and freak out some friends by turning an old Garfield paperback into a wailing orgy of dissonance, you can be up and running for just a few dollars (excluding the cost of the beers).

A common use of piezo mics among experimental musicians is in “noise boxes,” ungainly contraptions in which household objects are mounted around and amplified by piezo mics. I’ve built a few of these, including an old cookie tin I outfitted with various springs and filled with Ping-Pong balls. When I shake the tin and turn the volume up, it sounds as if the springs and the Ping-Pong balls are role-playing the end of the world. People build noise boxes with combs, wires, silverware, rubber bands, fidget spinners, sandpaper, old saw blades — tiny orchestras of singing objects, monumentalized by the mics placed inside. Indeed, my hobby has made trash nights newly enticing, as I wander the neighborhood looking for garbage that might sound interesting. My wife loves my hobby and never teases me about it.

Earlier this summer, I visited a different windowless room for a performance by one of the grandmasters of piezo-mic mayhem: Justice Yeldham, an Australian noise artist known for attaching contact mics to large pieces of broken glass. Yeldham uses glass like a wind instrument, smooshing his face against the pane as he blows, hums, bites and otherwise imitates the world’s least subtle peeping Tom. The signal runs through a small metropolis of effects pedals that amplify and expand the resonances and sputterings of his mouth against the glass. One moment you hear John Coltrane playing a volcano, the next you hear a string section being squeezed through a toothpaste tube. It’s a high-stakes, smeary embouchure that can end with Yeldham’s face covered with blood. (He ended the performance I saw by suddenly breaking his instrument over his head, something Yo-Yo Ma has yet to do.) This may sound like a gimmick — G.G. Allin for grad students — but Yeldham coaxes a truly amazing variety of sounds from his shard.