Marimba is an idiophone coupling mechanical and air resonances through the NFC mechanism

Evidence

One does not always want to maximize energy flow across junctions between two parts of a system. We need the impedance mismatch at the bell end of a trumpet or clarinet to cause reflections and define its resonance frequencies. Impedance mismatches are carefully controlled to achieve desirable timbre in wind and string instruments. For string instruments, large mismatches are required at the points between which strings are stretched, lest the vibrations drain away too rapidly, rendering the string frequencies ill-defined. The infamous wolf note of cellos is a breakdown of this requirement (see section 18.7)—a near impedance matching where none was wanted. — Eric J. Heller, Why You Hear What You Hear- An…, 83 (#expands, via linked claim)

Categorization

• XREF: connects to: Marimba resonators amplify sound by capturing near-field energy that would otherwise short-circuit; Marimba-like instruments with joined bars and resonators arose independently on three continents; Instrument design exploits impedance mismatches to create resonance and timbre — Eric J. Heller, Why You Hear What You Hear- An…, 83

Broader Connections

• Instrument design exploits impedance mismatches to create resonance and timbre #expands (0.85) — Eric J. Heller, Why You Hear What You Hear- An…, 83