High harmonics must be dropped in the treble because they become inaudible

Evidence

In this way, the mixture adds brilliance to the overall sound by enhancing high harmonics at the bass end of the keyboard, but these would become inaudible (and the pipe length would be too short to be practical) if continued to the treble. — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 1566

Categorization

• XREF: Connects to the psychoacoustic limits of hearing and to earlier critical-bandwidth discussion of which harmonics stay audible. — connects to: Listeners lose the ability to identify instruments once onset and offset phases are removed. — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 1470; Lacking high harmonics makes instruments sound dark or dull — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 1476; Unresolved harmonics smear together as frequency rises (+6 more)

Broader Connections

• Harmonics above the seventh exceed auditory filter bandwidth and cease to be resolved #corroborates (0.95) — David Howard, Jamie Angus, coustics and Psychoacoustics, 1528
• Harmonics resolve only while their spacing exceeds the ear’s ERB #corroborates (0.90)
• Harmonics are unresolved when critical bandwidth exceeds harmonic spacing. #corroborates (0.85) — David Howard, Jamie Angus, coustics and Psychoacoustics, 883
• Higher pitched notes spread harmonics so wide that formant peaks vanish #corroborates (0.80)
• Notes lacking reinforced upper harmonics play wobbly and degraded #complicates (0.80)
• Unresolved harmonics smear together as frequency rises #complicates (0.75)
• Treble boost in loudness controls damages sound quality unnecessarily #complicates (0.70) — Toole, Floyd E, Sound reproduction- the acoustics and…, 917