Peak dissonance between two tones occurs at a quarter critical band separation

Evidence

The level of consonance and dissonance has been measured with listening tests for two sinusoids as a function of the difference in frequency, and the result is presented in Figure 11.12 (Rossing et al., 2001). When the frequencies are the same, consonance has a maximum value of 1.0 and dissonance 0.0. When the frequency difference is about a quarter of the critical band, dissonance has its maximum and consonance is at its minimum. After this, consonance approaches asymptotically the value 1.0 when the frequency difference is increased. — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 1291

Categorization

• DEFINE: Defines the quantitative relationship between critical band spacing and perceived consonance/dissonance, a core perceptual-acoustics anchor.
• XREF: Connects to critical band / auditory filter concepts from earlier chapters on the auditory periphery and to how masking and partial masking shape perception. — connects to: Consonance and dissonance judgments stem from critical bandwidth mechanics — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 934