Wind chimes make sound the same way a xylophone or tubular bell does: each hanging tube is a free-free bar whose fundamental pitch depends on its length, wall thickness, and material stiffness, so longer or heavier tubes ring lower and shorter ones ring higher. Unlike a plucked string, a struck metal tube vibrates with inharmonic overtones (not simple whole-number multiples of the fundamental), which is part of what gives chimes their shimmering, bell-like timbre rather than a clean musical note. A striker or "wind catcher" paddle hangs in the middle and gets pushed around by moving air, knocking it into the tubes to trigger the chime. Even a light breeze of about 5-11 km/h (roughly Beaufort force 2) is enough to set lightweight tubes swinging and colliding. Wind chimes have been used across cultures for roughly 3,000 years, from bronze bells in ancient China to Japanese furin and Western garden chimes, often tied to feng shui beliefs about channeling beneficial energy.

• Tube fundamental frequency for a free-free bar scales roughly with thickness over length squared, so doubling tube length drops the pitch by about a factor of four.
• Common materials: aluminum (bright, sustained ring), bamboo (soft, warm, heavily damped), copper and bronze (mellow, complex overtones).
• A light breeze around 5-11 km/h (Beaufort scale 2) is already enough to audibly move most garden wind chimes.
• Chime tube overtones are inharmonic, unlike a guitar string's near-integer harmonic series, giving chimes their bell-like shimmer.
• Ancient Chinese bronze bells and wind bells date back roughly 3,000 years; Japanese furin became popular in the Edo period.
• The central striker (often a star, ball, or sail-shaped "wind catcher") increases surface area so gentle air currents can move it enough to strike the tubes.
• Larger-diameter, thicker-walled tubes ring longer (less internal damping) than thin-walled tubes of the same length.