Originally Posted by RYM

Stoner Rock combines Blues Rock, the psychedelic elements from Psychedelic Rock, and the repetitive riffs of Doom Metal. Guitars are tuned low, the bass is heavy and tempo is mostly slow-to-mid. The vocals and production are usually raw.

The term stoner rock comes from the genre's connection with the use of marijuana, stoner being a slang term for a user of cannabis. It is sometimes believed that the bass heavy and psychedelic sound is meant to enhance the effects of drugs. The roots are in '60s and '70s bands like Black Sabbath and Blue Cheer, but what is called Stoner Rock today was pioneered by Californian bands such as Kyuss, Sleep and Fu Manchu.

Originally Posted by Wikipedia

Stoner rock or stoner metal[1] is a subgenre of heavy metal,[2][3] combining elements of psychedelic rock, blues rock, traditional heavy metal and doom metal. Stoner rock is typically slow-to-mid tempo and features a bass-heavy sound,[4] melodic vocals, and 'retro' production.[5] The genre emerged during the early 1990s and was pioneered foremost by the Californian bands Kyuss[6] and Sleep.[7]