Liquid Tension Experiment (LTE) is an instrumental progressive rock/metal supergroup, founded by Dream Theater's former 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 (keyboard) and progressive rock icon Tony Levin (bass, Chapman Stick) of King Crimson and Peter Gabriel's band 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 (Dixie Dregs, Kansas (band), Deep Purple) and Jim Matheos (Fates Warning) 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 combo was formed as a side project to Dream Theater in 1997. Both Mike and John confirmed on the 5 Years in a Livetime DVD commentary, that Rudess was asked to join Dream Theater largely because of the success of Liquid Tension Experiment, and the chemistry of the three working together. He had already declined a previous offer to join in 1994 and instead became a member of the Dixie Dregs, known for complex, "Southern fusion" instrumental music.
Liquid Tension Experiment released two albums, Liquid Tension Experiment (1998) and Liquid Tension Experiment 2 (1999) on Magna Carta Records. They also played a few live shows in New York, Philadelphia, Los Angeles and London. Mike Portnoy has previously stated in numerous interviews (and on his web site FAQ) that there would not be a third LTE album, as 3/4 of the band is in the current Dream Theater line-up and the material would be too similar; yet there can always be live shows with the same line-up. In 2007 however, he said that a third release is possible, but that his problems with the Magna Carta label are more of an obstacle than getting the band members together to record. A situation that had to do with the company that released the Liquid Drum Theater VHS tape using video footage of Liquid Tension Experiment in the studio without getting the required permission of Magna Carta. Mike Portnoy came back to Magna Carta in 2007 to release the Liquid Trio Experiment's "Spontaneous Combustion" Sessions.
Several songs and riffs from the project have been incorporated into Dream Theater's live performances, such as "Instrumedley" from Live at Budokan.
On October 4, 2007, it was announced that LTE would headline NEARfest 2008 in June. On March 29, 2008, six Liquid Tension Experiment tour dates in June 2008 were announced to celebrate the bands 10 year anniversary as well to create a "whole new musical experiment".
Liquid Tension Experiment released a multi-disc boxed set of tour highlights from their 2008 tour, including complete shows from New York and Los Angeles on DVD and CD (the L.A. show also on Blu-ray), the Liquid Trio Experiment 2 recording from Chicago (q.v. below), and a disc of improvisations from other shows on the tour. The New York and Los Angeles shows were also released separately on CD or DVD, all through Dream Theater's official bootlegs website Ytsejam Records.
On July 19th 2012, at Dream Theater's second show on Huntington NY, Tony Levin joined Petrucci, Rudess and Mike Mangini (Dream Theater's current drummer) onstage to perform Paradigm Shift.
Later in 2012, Portnoy performed Acid Rain live with his yet unnamed band with Derek Sherinian, Tony MacAlpine and Billy Sheehan. They recorded a live DVD in Tokyo including Acid Rain.