Anti-noise window: Subjective perception of active noise reduction and effect of informational masking

TL;DR

This study evaluates an active-noise-control window's perceptual effectiveness in urban settings, showing it reduces annoyance and improves pleasantness despite minimal objective noise reduction, especially when combined with informational masking.

Contribution

It provides novel perceptual insights into active noise control combined with informational masking, highlighting their combined effects on acoustic comfort in real-world scenarios.

Findings

ANW reduces perceived annoyance and loudness despite minimal decibel reduction.

Adding maskers enhances acoustic comfort, especially with water masking increasing loudness.

ANC combined with maskers significantly lowers perceived annoyance compared to ANC alone.

Abstract

Reviving natural ventilation (NV) for urban sustainability presents challenges for indoor acoustic comfort. Active control and interference-based noise mitigation strategies, such as the use of loudspeakers, offer potential solutions to achieve acoustic comfort while maintaining NV. However, these approaches are not commonly integrated or evaluated from a perceptual standpoint. This study examines the perceptual and objective aspects of an active-noise-control (ANC)-based "anti-noise" window (ANW) and its integration with informational masking (IM) in a model bedroom. Forty participants assessed the ANW in a three-way interaction involving noise types (traffic, train, and aircraft), maskers (bird, water), and ANC (on, off). The evaluation focused on perceived annoyance (PAY; ISO/TS 15666), perceived affective quality (ISO/TS 12913-2), loudness (PLN), and included an open-ended qualitative assessment. Despite minimal objective reduction in decibel-based indicators and a slight increase in psychoacoustic sharpness, the ANW alone demonstrated significant reductions in PAY and PLN, as well as an improvement in ISO pleasantness across all noise types. The addition of maskers generally enhanced overall acoustic comfort, although water masking led to increased PLN. Furthermore, the combination of ANC with maskers showed interaction effects, with both maskers significantly reducing PAY compared to ANC alone.