Preliminary Investigation of Perceived Sound Quality for High-Fidelity Premolded Hearing Protection Devices.

High-fidelity premolded earplugs (HiFi HPDs) are designed to provide relatively uniform attenuation across frequencies. The primary goal of this study was an exploratory analysis of relationships between attenuation and perceptions of sound quality. Participants were 16 adults tested using commercial HiFi HPDs marketed for use at recreational music events. Survey responses did not reveal statistically significant differences in perceived sound quality across HiFi HPD brands. However, increases in music quality ratings were correlated with decreases in average attenuation at 3, 4, and 6 kHz and increasing uniformity of attenuation. The correlations were weak, however, explaining only about 15% of the variance. The data suggest listeners may prefer HiFi HPDs that provide more uniform sound attenuation at frequencies from 0.25 to 4 kHz and less attenuation from 3 to 6 kHz. The data are consistent with existing suggestions that HiFi HPDs with moderate but uniform attenuation may be preferred by those listening to music.