SOUTHAMPTON, Pa. — The Knabe baby grand did a cartwheel and landed on its back, legs poking into the air. A Lester upright thudded onto its side with a final groan of strings, a death-rattling chord. After 10 pianos were dumped, a small yellow loader with a claw in front scuttled in like a vicious beetle, crushing keyboards, soundboards and cases into a pile.

The site, a trash-transfer station in this town 20 miles north of Philadelphia, is just one place where pianos go to die. This kind of scene has become increasingly common.

The value of used pianos, especially uprights, has plummeted in recent years. So instead of selling them to a neighbor, donating them to a church or just passing them along to a relative, owners are far more likely to discard them, technicians, movers and dealers say. Piano movers are making regular runs to the dump, becoming adept at dismantling instruments, selling parts to artists, even burning them for firewood.

“We bust them up with a sledgehammer,” said Jeffrey Harrington, the owner of Harrington Moving & Storage in Maplewood, N.J.