One of the Echo Nest attributes calculated for every song is ‘speechiness’. This is an estimate of the amount of spoken word in a particular track. High values indicate that there’s a good deal of speech in the track, and low values indicate that there is very little speech. This attribute can be used to help create interesting playlists. For example, a music service like Spotify has hundreds of stand-up comedy albums in their collection. If you wanted to use the Echo Nest API to create a playlist of these routines you could create an artist-description playlist with a call like so:
However, this call wouldn’t generate the playlist that you want. Intermixed with stand-up routines would be comedy musical numbers by Tenacious D, The Lonely Island or “Weird Al”. That’s where the ‘speechiness’ attribute comes in. We can add a speechiness filter to our playlist call to give us spoken-word comedy tracks like so:
It is a pretty effective way to generate comedy playlists.
I made a demo app that shows this called The Comedy Playlister. It generates a Spotify playlist of comedy routines.