Over-confining sound in resonators can backfire through internal dissipation.

Evidence

Bottom line: If we keep sound partially confined, it can be resonantly enhanced and become even louder, but more confinement in an attempt to take advantage of resonance may backfire if the sound is being dissipated internally before it gets a chance to leave. — Eric J. Heller, Why You Hear What You Hear- An…, 1053

Categorization

• XREF: Directly relevant to musical instrument design and the physics of why soundboards and resonating cavities must be tuned, not just bigger, for loudness.