自行车链条咬合

Close-mic recording of a bicycle chain engaging a rear cassette cog: one short dry mechanical clack, solid body in the 1–3 kHz range with a small low thump near 250 Hz, and a brief metal-on-metal scrape dying away within 40 ms. Rounded attack, mid-focused. No high-frequency tick, no sparkle, no sizzle, no hiss, no metallic ring, no room reverb. Mono, dry, 0.5 seconds.no high-frequency tick / no sparkle / no sizzle /