Blast beats refer to fast tempo drumming that originated in jazz music. It would be taken to the next level by extreme metal, death metal, black metal and grindcore bands where drumming consists of 180-280 beats per minute. Blast beats alternate between the bass drum and snare and are synced with the ride and/or hi hat cymbal. The sound is violent and brings to mind images of machine gun fire. Extreme metal band, Napalm Death, invented the term blast beats to describe this violent drum sound that they began using after hearing the Swedish hardcore group Asocial. This type of drumming is very prevalent today in all the genres of extreme metal.