Typically, the electric guitar is performed with a large amount of reverb or audio feedback while vocals, if present, are usually growled or screamed. Songs often lack beat or rhythm in the traditional sense and are typically very long. The experience of a drone metal performance has been compared by novelist John Wray in The New York Times to listening to an Indian raga in the middle of an earthquake. Wray also states, "It's hard to imagine any music being heavier or, for that matter, very much slower." A pioneer band of drone metal called Sunn O))) has indicated a kinship with sound sculpture. Jan Tumlir indicates a "sustained infra-sound rumble of sub-bass—so-called brown noise".