Simple integer frequency ratios between notes produce the greatest measured consonance

Evidence

Dissonance has been measured for different ratios between the fundamental frequencies of two notes. Figure 11.14 shows the degree of dissonance and consonance when the fundamental frequency of one of the sounds stays at 250 Hz, and the frequency of the other sound changes from 250 Hz to 530 Hz (Plomp and Levelt, 1965). Each sound consists of the fundamental frequency and five harmonic components. Perfect consonance is obtained with frequency ratios 1:1 and 1:2. Consonance has a local maximum with all simple integer ratios, such as 2:3, 3:4, 3:5, and so on, and a minimum in between. — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 1296

Categorization

• SHARE: Good for a music-theory or psychoacoustics-minded friend: the Plomp-Levelt curve empiricizes why just intonation’s simple integer ratios sounded ‘pure’ to pre-modern theorists.
• XREF: This is the quantitative core beneath Pythagorean tuning and the historical ‘music of the spheres’ claims about integer ratios.