Sonic logos have been recognized by modern marketers as one of the most essential elements of sensory marketing that establish a brand’s identity and render a brand memorable. This paper examines the emotional implications of sonic logos. An experiment investigating the emotional impact of four versions of a fictional radio advertisement (three versions that feature a sonic logo performed on the violin, the piano, the trumpet, and one that does not feature a sonic logo) was conducted. Specifically, a text analysis of participants’ comments regarding the brand and an analysis of the participants’ perceived warmth of the nonprofit brand was conducted. The influence of the four stimuli on respondents’ willingness to spread positive word of mouth was also analyzed. Results suggest that the piano sonic logo produced the most positive comments, but that the perceived warmth of the brand was highest for the group that listened to the trumpet sonic logo. The violin treatment group scored the lowest perceived warmth of the brand and generated comments that were less positively valanced than the other groups. Furthermore, the trumpet treatment groups’ willingness to spread positive word of mouth was highest among the four groups.