This letter contains a description of an inversion technique that allows for separation of speech and noise and its application to quantifying the acoustic effects of wide-dynamic-range compression (WDRC) on speech in background noise. Three main findings are reported: that fast-acting WDRC further degrades signal-to-noise ratio; that the effective compression ratio is lower for speech in noise than speech in quiet; and that in contrast to speech in quiet, the amplitude envelope of speech is mostly unaffected when compressed in background noise.

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