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Performer’s perception of own sound

It is a common experience that people find recordings of their own voice strange and weak, missing the low frequency emphasis typically perceived by one self.

The reasons for the perceived difference are several:

1) Low-mid frequencies are easily transmitted directly through bone and tissue from the human voice to inner ear.

2) Direct air-borne sound via mouth to ear is diffracted, with the result that  higher frequencies are being attenuated, providing a low pass filter effect to the sound transmission.

3) The ear is in the near-field of the source (mouth opening and vibrating cheek and neck, etc), so low-frequency pressure gradients are relatively stronger than on distances large compared to the wavelength. To the extent that our hearing is pressure gradient sensitive, this may add to the low frequency emphasis.

When it comes to sound from performers’ own musical instruments, there may be more or less similarities to the effects on own voice. Wind instruments like saxophone creates a vibrating air-column inside the vocal tract resulting in low frequency effects that may be similar to the human voice. The violin is has bone-contact with the head of the performer, while instruments like the piano has no direct mechanical contact with the performer.

Own Perception Filter

A. What are the properties of a filter that, applied to the air borne signal picked up at, say 1m, creates a sound quality that the performer recognizes as equivalent to the performers perceived quality of total (air-borne and mechanical) direct sound transmitted the performers ear?

B. Can the filter in A. help us to understand how direct own sound masks the sound from other sources, e.g. in an orchestra?

C. Can the filter in A. help us to understand how direct own sound masks reflected sound from own voice / instrument?

D. Can the filter in A. help us to predict a threshold or a reference level for perceiving other sounds in general?

For example, impulse responses in prediction software like ODEON and others, could be compared with reference data like those achieved in D, in order to evaluate support mutual hearing in stage acoustics.

A student project at NTNU, Trondheim, Norway in 2005 did not lead to a significant answer to A, since the resulting filters varied in ways that appeared to be random. The explanation could lie in too few subjects in the test, or just that the filter varies more over the population than expected.

A proper technique to achieve an answer to the questions above should be developed, starting with A.

Interrelated akuTEK research topics

Current view in akuTEK Research is that the following topics are strongly related: stage acoustics, rehearsal rooms, performer’s perception, perceived reverberation. Stage acoustics and rehearsal room acoustics are important in order to develop musicians, orchestras and provide for good playng conditions—to the benefit of the listeners—and must be supported by knowledge of performer’s perception in general, and perceived reverberance in particular.

On perceived spectral distortion in rooms and effect of vibrato, etc: Tonal response in rooms (Microstructure of room acoustic FR) .

Performers perception of sound level  from own voice or instrument

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