Stacking three tubes tuned to octave and twelfth enrich an instrument’s timbre

Evidence

The Javanese angklung uses three of these per note, the upper two tuned an octave and a twelfth above the lowest one, respectively, providing a more pleasing tone with significant strength in three partials, one for each tube. The three are held on a common rack so that when shook, all three are struck at once. Each rack is one note, so complete instruments are large. — Eric J. Heller, Why You Hear What You Hear- An…, 1909

Categorization

• XREF: Connects to the reader’s question on why we hear what we hear — deliberate partial-stacking as a design to enrich perceived tone, echoing overtone-series anatomy.