Mean subjective responses ((a) Annoyance, (b) Arousal, and (c) Valence) as a function of combined ASHP and BN sound pressure levels at the listener’s position, shown separately for BN levels of 31.5 dB(A) and 39.5 dB(A). Points indicate mean responses at each sound level; lines show linear trend fits. Responses were rated on different scales (Annoyance: 0–10; Valence and Arousal: 1–9) but are plotted on a common y-axis for alignment, and are restricted to the range covering the observed data for clarity.