Identification of concert halls was studied to uncover whether the early or late part of the acoustic response is more salient in a hall's fingerprint. A listening test was conducted with auralizations of measured halls using full, hybrid, and truncated impulse responses convolved with anechoic symphonic music. Subjects identified halls more reliably based on differences in early responses rather than late responses, although varying the late response had more effect on acoustic parameters. The results suggest that in a typical situation with running symphonic music, the early response determines the perceptual fingerprint of a hall more than the late response.