Vocal quartets empirically drift flat as just intonation predicts

Evidence

Figure 4.44 shows the measured results for a quartet where the average f0 for each sung note of each chord has been used (Howard, 2007a). The measured results have a similar trend to that predicted but with some variation in detail. The singers tend to drift flat more gently than the prediction in the early stages then more rapidly afterward, with individual singers generally moving together except for the bass, whose pitch swings are quite wide from chord to chord. The soprano and to some extent the alto in this quartet seem to be reluctant to allow the pitch to drift any further flat toward the end, almost maintaining it in the position it has reached, somewhat against the efforts of the tenor and to some extent the bass to shift it further in line with the prediction. The overall measured pitch change is quite close to the semitone flat shift — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 1382

Categorization

Category: Causal Relationships

• SHARE: For an a capella choir director or singer — a nice finding about how intentionally singers resist the drift.

Related

• A cappella just intonation makes a group’s overall pitch drift across key modulations (similarity 0.87)
• Just-tuned chord progressions predict key drift of a full semitone (similarity 0.85)
• Singing just-tuned chords predicts rapid pitch drift flat (similarity 0.84)
• Singing in just intonation causes pitch drift when modulating through keys (similarity 0.81)

Broader Connections

• Just-tuned chord progressions predict key drift of a full semitone #expands (0.85) — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 1381
• Chord consonance is maximized when singers’ fundamentals are integer-related harmonics #corroborates (0.75) — David Howard, Jamie Angus, coustics and Psychoacoustics, 1390