Controlled listening tests were conducted on five different in-ear (IE) headphone target curves measured on the latest ITU-T Type 4.3 ear simulator (e.g. Bruel & Kjaer Head & Torso Simulator Type 5128). A total of 32 listeners rated each target on a 100-point scale based on preference for three different music programs with two observations each. When averaged across all listeners, two target curves were found to be equally preferred over the other choices. Agglomerative hierarchical clustering analysis further revealed two classes of listeners based on dissimilarities in their preferred target curves. Class One (72% of listeners) preferred the top two rated targets. Class two (28% of listeners) preferred targets with 2 dB less bass and 2 dB more treble than the target curves preferred by Class 1. Among the demographic factors examined, age was the best predictor of membership in each class.
