Optimizing the Decay Range in Room Acoustics Measurements Using Maximum-Length-Sequence Techniques

A practical examination of the factors influencing the decay range of room acoustics measurements using maximum-length-sequence measurement techniques is presented. A series of systematic measurements were made to examine the effects of output signal level, ambient noise level, sequence length, and number of averages on the decay range of measured sound decays. The effects of small amounts of time variation and the sequence length relative to the measured reverberation times are also included. A step-by-step approach to optimizing the decay range of measured room responses concludes the discussion.