Sharp low- and high-frequency limits on musical chord recognition

This research is concerned with the recognition of major and minor triads in low- and high-frequency regions. Its specific aim is to determine the limitations on the frequency range within which musicians can recognize minor and major triads. Twelve subjects were tested in a task in which the stimuli were successions of minor and major triads centered on frequencies ranging from 39 to 8372 Hz. Subjects were asked to say, for each triad, if it had or did not have the characteristics of a minor or a major chord. Minor and major chords were presented in separate blocks. Results show that subjects failed to recognize minor and major triads when placed below approximately 120 Hz and above approximately 3000 Hz. Statistical analysis of results also demonstrates that the failure to recognize triads differed at the low- and high-frequency ends of this range--occurring much more abruptly at the low-frequency border. The failures at the borders, and some differences there in the identifiability of major and minor triads, may possibly be related to inadequate spatial resolution of components at the lower-frequency border and to frequency limitations on phase-locking at the higher.