Liquid Tension Experiment is an instrumental progressive rock/metal supergroup, founded by Dream Theater's drummer Mike Portnoy in 1997. The band has released two albums through Magna Carta Records. A third album, with the absence of John Petrucci, along with a fourth album, with the absence of Jordan Rudess (mostly), were released in 2007 & 2009 respectively, both under the name "Liquid Trio Experiment". Mike Portnoy invited Jordan Rudess and progressive rock icon Tony Leving to join him. In his instructional video "Liquid Drum Theater", Portnoy said that his first choice for the guitar was Dimebag Darrell, but he was unable to join because of conflicting schedules. Two other primary choices, Steve Morse and Jim Matheos were also unavailable. Portnoy then turned to fellow Dream Theater member John Petrucci to fill the position (despite initially wanting to keep the project completely separate from Dream Theater). The group was formed as a side project to Dream Theater in 1997. Liquid Tension Experiment released two albums, Liquid Tension Experiment (1998) and Liquid Tension Experiment 2 (1999) on Magna Carta Records.