A re-examination of duplex perception with musical chords

In duplex perception, an acoustic element differing from the others in receiving ear or form (e.g., harmonic complex or sinusoidal) contributes simultaneously to two distinct percepts. Speech has received the most attention, but duplex perception also occurs with musical chords. By one account, a specialist processing "module" (e.g., phonetic) has priority access to acoustic information (precedence) that is not subject to scene-analysis constraints. Precedence received initial support from claims of better performance for speech than non-speech judgments of the same stimuli, but experiments controlled for criterion differences and unintended cues challenged this interpretation. This approach is extended here to three-note chords comprising tonic and fifth complexes and a sinusoidal third (30-dB presentation range) defining the mode (major/minor). In experiment 1, listeners first heard a chord and identified its mode; chords were then preceded by two successive sinusoids-one matching the third, the other mistuned-and listeners identified the matching tone. In experiment 2, for tone discrimination, the tonic and fifth were replaced by a single complex crafted to produce equivalent masking of the third but to remove an unintended mode cue. The notion of precedence was not supported; there was no evidence of better performance for musical than non-musical judgments of the same stimuli.