“Music hath charms to soothe the savage breast. To soften rocks, or bend the knotted oak.” It’s an old saying (sometimes attributed to William Shakespeare but actually written by William Congreve), but it holds true. Music can make us happy when we’re sad, sad when we’re happy, nostalgic about the past, or excited about the future. It can inspire us to work out or help us relax, speed up our heartbeat or lull us to sleep. 

There’s music for every mood and every occasion, and it’s not always by different artists. Some musicians are known for their versatility of subject matter and approach, not only embracing different genres but also spanning a vast emotional range over the course of their careers. 

Based on a paper published as a part of a conference on artificial and computational intelligence held in Brazil, 24/7 Tempo has determined the musicians with the most emotionally diverse output since the middle of the last century. We used data categorizing songs by themes such as sadness, movement/places, and family/spiritual to reveal the probability that two random songs in an artist’s catalog will be thematically distinct. (Here is the most popular song every year since 1970.) 

Click here to see the musicians with the most diverse output
Click here to read our detailed methodology

Our findings might come as a surprise to some people. The list is dominated by musicians who haven’t been in the charts for decades. Some of the names might not even be known to Gen Z listeners. The top five are B.B. King, Perry Como, Nina Simone, J.J. Cale, and Ella Fitzgerald, all of them deceased. (Here are 35 musicians with legendarily long careers.)

It’s interesting to speculate why there are almost no contemporary artists on our list. One reason, of course, is that the longer musicians have been performing, the more time they have to experiment with different styles. Another reason may be the segmentation of taste due to the recent proliferation of satellite radio and streaming services – which may discourage musicians and their audiences alike from venturing outside their comfort zones.