If a string quartet is a genre of chamber music, what is the genre of music for a rock ensemble?
I would argue that the Dixie Chicks is a genre of rock ensemble.
http://www.gepr.net/genre2.html
The Dixieland Jazz Band would be one genre of rock ensemble. The Who would be an entirely different genre.
I would like to clarify that the Dixie Chicks is generally considered a country music group rather than a rock ensemble. However, I understand that your overall question is about the genre of music for a rock ensemble.
The genre of music for a rock ensemble is typically referred to as rock music. Rock music is a broad genre that emerged in the United States in the 1950s, characterized by a heavy emphasis on electric guitars, drums, and a strong backbeat. It encompasses various subgenres such as classic rock, alternative rock, punk rock, and many more.
To learn more about different genres of music, you can explore websites like the one you mentioned, GEPR (http://www.gepr.net/genre2.html), which provides a comprehensive list and description of various music genres. Additionally, you can listen to music from different artists and bands within the rock genre to familiarize yourself with the different subgenres and their unique characteristics.