Stoner rock or stoner metal is a musical subgenre which combines elements of heavy metal, psychedelic rock, blues rock, acid rock, and doom metal. The term desert rock is often used interchangeably with the term "stoner rock" to describe this genre; however, not all stoner rock bands would fall under the descriptor of "desert rock." Stoner rock is typically slow-to-mid tempo and features a heavily distorted, groove laden bass-heavy sound, melodic vocals, and "retro" production. The genre emerged during the early 1990s and was pioneered foremost by the Californian bands Kyuss and Sleep.