THE NOISINESS OF DIFFUSE SOUND FIELDS AT HIGH INTENSITIES.

Abstract

An experimental study was conducted to establish the relationships between the subjective noisiness, frequency and sound pressure level of random noise in a diffuse acoustic field. The experiments were performed in a fabric enclosure installed within a 100,000 cubic foot reverberant chamber. Twenty-four subjects took part. The growth of noisiness with sound pressure level of an octave band of noise centered at 1000 Hz was determined. The variation of noisiness with frequency was measured at four perceived noise levels between 78 and 104 PNdB. For comparison purposes, one equal noisiness contour was also determined for free field listening conditions in a progressive wave chamber. The results indicated that currently used noisiness growth functions are adequate but that the equal noisiness contours may need some modification at low frequencies. Also the contour shapes vary as sound pressure level increases indicating relatively greater noise sensitivity at both high and low frequencies. (Author)

Document Details

Document Type
Technical Report
Publication Date
Aug 01, 1969
Accession Number
AD0708816

Entities

People

  • J. B. Ollerhead

Tags

DTIC Thesaurus Topics

  • Acoustic Fields
  • Free Field
  • Frequency
  • Intensity
  • Sound Pressure

Readers

  • Acoustics.
  • Materials Science and Engineering.