Papers Published

  1. Hebrank, J.H. and MacDuff, J.N. and Wright, D., Improvements to a small free-field listening room, J. Sound Vib. (UK), vol. 35 no. 1 (1974), pp. 139 - 42 .
    (last updated on 2007/04/07)

    An inexpensive free-field listening room (7 ft 8 in×5 ft 9 in×6 ft 7 in high) was designed and constructed with walls made of 5 inch high acoustical foam wedges backed by 11/2 inch foam and a 31/2 inch layer of building-grade Fiberglas. The composite wall construction creates a rugged, non-irritating surface that is highly absorbent and relatively inexpensive. Deviations from the inverse square law are less than 2.3 dB above 500 Hz. Reverberation from a 40 ms 1000 Hz pulse is 31 dB below the original pulse. Results of these two tests are compared with measurements by Marsh (1968) in a room of similar volume having flat 4 inch foam walls

    anechoic chambers;architectural acoustics;