This study examined the subjective perception of musical octaves. It tried to explore how the sustention of the base tone and the method of ascending/descending limits affect the frequency of the tuned octave. A Method of Limits experiment was performed in which the subject was presented with either a sustained or unsustained base note and was made to tune for the note perceived as an octave higher. Results showed that the perceived octave had a frequency ratio smaller than 2:1 for sustained base tones and greater for unsustained base tones. Tuning with ascending limits over a sustained base tone produced the most accurate octave. No relationship was discovered between frequency and the frequency ratio of the perceived octave.
Graph 1. Sustained and Unsustained Base Tones
Graph 2. Unsustained Base Tones with Ascending and Descending Limits
Graph 3. Sustained Base Tones with Ascending and Descending Limits