Frequency range 20 to 15 000 c/s, under stated conditions, relations between sound pressure level and frequency for pure-tones of equal loudness, values for threshold of hearing. For otologically normal persons aged 18 to 25. Correction formulae for otologically normal persons up to 60 years.
BS 3383:1961
Original price was: $264.16.$132.00Current price is: $132.00.
Normal equal-loudness contours for pure tones and normal threshold of hearing under free-field listening conditions
BSI Group , 05/19/1961
