Reverberation low-pass filters speech modulation while noise raises its floor

Evidence

The reverberation smooths the change of the envelope in time, acting as a low-pass filter for the envelope and thus also for modulation. The effect of additional noise is seen from the increase in the minimum value of the envelope. — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 2411

Categorization

• XREF: Connects to how the modulation transfer function decomposes a room’s degradation of intelligibility into these two separable mechanisms.