Studying similarities and differences between speech and song provides an opportunity to examine music’s role in human culture. Forty participants divided into groups of musicians and nonmusicians spoke and sang lyrics to two familiar songs. The spectral structures of speech and song were analyzed using a statistical analysis of frequency ratios. Results showed that speech and song have similar spectral structures, with song having more energy present at frequency ratios corresponding to those ratios associated with the 12-tone scale. This difference may be attributed to greater fundamental frequency variability in speech, and was not affected by musical experience. Higher levels of musical experience were associated with decreased energy at frequency ratios not corresponding to the 12-tone scale in both speech and song. Thus, musicians may invoke multisensory (auditory/vocal-motor) mechanisms to fine-tune their vocal production to more closely align their speaking and singing voices according to their vast music listening experience.