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Combination tones at frequencies greater than the primary tones
Science (New York, N.Y.)
|August 10, 1979
Summary
Audible combination tones at higher frequencies were measured using a contralateral probe tone. These tones, with amplitudes 20-40 dB below primary tones, are explained by binaural interaction.
Area of Science:
- Auditory neuroscience
- Psychoacoustics
Background:
- The generation and perception of combination tones, particularly those exceeding primary frequencies, present a long-standing challenge in auditory science.
- Previous research has struggled to fully explain the mechanisms behind these higher-frequency combination tones.
Purpose of the Study:
- To demonstrate and measure audible combination tones at frequencies higher than the generating primary tones.
- To investigate the role of binaural interaction in the perception of these combination tones.
Main Methods:
- Utilized primary tones at frequencies f1 and f2.
- Employed a contralateral probe tone to establish binaural interaction with specific combination tones.
- Measured the frequencies and amplitudes of the resulting combination tones.
Main Results:
- Successfully demonstrated and measured combination tones, including those at frequencies like f1 + f2 - f1.
- The estimated amplitudes of these higher-frequency combination tones were found to be significantly lower than the primary tones, ranging from 20 to 40 decibels below.
Conclusions:
- Binaural interaction, facilitated by a contralateral probe tone, is a viable method for demonstrating and measuring higher-frequency combination tones.
- The observed amplitudes suggest a specific mechanism for the generation or perception of these complex auditory phenomena.
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