Loading a source with a chamber is central to all musical instruments

Evidence

The proximity resonance principle, (loading the source), could not be more important to musical instruments, including voice. We will reinforce this concept many times in different ways. — Eric J. Heller, Why You Hear What You Hear- An…, 536

Categorization

• DEFINE: Introduces and names the ‘proximity resonance’ / ‘loading the source’ concept as a unifying principle for the whole book.
• XREF: connects to: Every stringed instrument is analyzable as a sound source plus modifiers — David Howard, Jamie Angus, coustics and Psychoacoustics, 1092