In recent years, psychological models of perception have undergone reevaluation due to a broadening of focus toward understanding not only how observers perceive stimuli but also how they subjectively evaluate stimuli. Here, we investigated the time course of such aesthetic evaluations using a gating paradigm. In a series of experiments, participants heard excerpts of classical, jazz, and electronica music. Excerpts were of different durations (250 ms, 500 ms, 750 ms, 1,000 ms, 2,000 ms, 10,000 ms) or note values (eighth note, quarter note, half note, dotted-half note, whole note, and entire 10,000 ms excerpt). After each excerpt, participants rated how much they liked the excerpt on a 9-point Likert scale. In Experiment 1, listeners made accurate aesthetic judgments within 750 ms for classical and jazz pieces, while electronic pieces were judged within 500 ms. When translated into note values (Experiment 2), electronica and jazz clips were judged more quickly than classical. In Experiment 3, we manipulated the familiarity of the musical excerpts. Unfamiliar clips were judged more quickly (500 ms) than familiar clips (750 ms), but there was overall higher accuracy for familiar pieces. Finally, we investigated listeners' aesthetic judgments continuously over the time course of more naturalistic (60 s) excerpts: Within 3 s, listeners' judgments differed between most- and least-liked pieces. We suggest that such rapid aesthetic judgments represent initial gut-level decisions that are made quickly, but that even these initial judgments are influenced by characteristics such as genre and familiarity.