No pure integer-ratio system can tune musical intervals without compromise.

Evidence

Just intonation is based purely on triads, where the frequencies of the triads C-E-G, G-B-D, and F-A-C have the ratio 4:5:6 and octaves are always tuned to 2:1. Unfortunately, with this method, many intervals are not in tune. For example, the interval D-A should have the ratio 1.5, but in this tuning it is 1.48, which is audibly mistuned. The Pythagorean tuning system has the greatest number of pure fifths and octaves. Unfortunately, the thirds are then mistuned. … We can thus conclude that no single method exists that tunes the seven notes of the diatonic scale so that all the intervals between the notes have intervals with simple integer ratios. Some methods have been developed to overcome this problem. For instance, the mean-tone temperament alters the Pythagorean tuning so that the fifths are tuned a bit narrower, which overcomes some problems of the system. — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 1306 (#expands, via linked claim)

Categorization

  • XREF: connects to: Uneven intervals make Just intonation scales impossible to transpose freely.; No tuning system can make all diatonic scale intervals perfectly consonant — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 1306; Musical scales universally favor intervals with small integer frequency ratios

Broader Connections