Random envelope fluctuations in 100-Hz-wide noise bands produce strong roughness

Evidence

Bands of noise often sound rough, although there is no additional amplitude modulation. This is because the envelope of the noise changes randomly. These changes become audible especially for bandwidths in the neighbourhood of 100 Hz, where the average rate of envelope change is 64 Hz (see Sect. 1.1). Therefore, roughness is particularly large at such bandwidths. For increasing bandwidth, the creation of roughness is limited by frequency selectivity. — Professor Dr.-Ing. Hugo Fastl, Professor Dr.-Ing. Eberhard, Psychoacoustics- Facts and Models, 1446

Bands of noise often sound rough, although there is no additional amplitude modulation. This is because the envelope of the noise changes randomly. These changes become audible especially for bandwidths in the neighbourhood of 100 Hz, where the average rate of envelope change is 64 Hz (see Sect. 1.1). Therefore, roughness is particularly large at such bandwidths. For increasing bandwidth, the creation of roughness is limited by frequency selectivity. Nonetheless, at very high centre frequencies noises can be produced which are still within the critical band but have a bandwidth of 1 kHz. Such a noise, although it is randomly amplitude modulated, sounds relatively steady and produces only a very small sensation of roughness. — Professor Dr.-Ing. Hugo Fastl, Professor Dr.-Ing. Eberhard, Psychoacoustics- Facts and Models, 1446

Categorization

• corroborated: 3 independent passages support this claim — Professor Dr.-Ing. Hugo Fastl, Professor Dr.-Ing. Eberhard, Psychoacoustics- Facts and Models, 1446
• XREF: connects to: Narrow-band noise behaves like a randomly amplitude-modulated pure tone.; Noise fluctuations within narrow critical bands raise the masking index; Fast amplitude modulations within a critical band produce roughness perception — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 1237 (+1 more)

Broader Connections

• Fast amplitude modulations within a critical band produce roughness perception #expands (0.80) — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 1237
• Narrow-band noise self-modulates at 0.64 times its bandwidth #corroborates (0.75) — Professor Dr.-Ing. Hugo Fastl, Professor Dr.-Ing. Eberhard, Psychoacoustics- Facts and Models, 3336