After the release of Michael Romeo's demo tape, The Dark Chapter, Symphony X was formed in April 1994. Besides Romeo, the original lineup included keyboardist Michael Pinnella and drummer Jason Rullo. The same year saw the band recording their self-titled debut. This was followed eight short months later by their tremendously received second album, The Damnation Game, which featured the new singer, Russell Allen, for the first time. They made a huge leap up the ladder in Autumn 1996 with the release of The Divine Wings Of Tragedy, which was especially well received in Europe, and which received high placing in the Readers' Polls of Europe's most important music magazines.

Accolades such as 'the best Progressive Power Metal band in the world' and 'the best Progressive Metal album of the year' were heaped onto Symphony X. March 1998 saw the release of their fourth studio album Twilight In Olympus, and the band's first, eagerly awaited concerts. Their fifth studio album, V - The New Mythology Suite, took Symphony X on a European tour in Autumn 2000. During the tour, they recorded their live double album, Live On The Edge Of Forever, in the legendary Paris venue Elysee Montmartre. The live album was released in October 2001, which documented the huge technical capabilities of the five band members. With their sixth studio work and latest release, The Odyssey, Symphony X united recognized progressive elements and their clean, sharp melodic vocals with a somewhat harder, rawer production. "The lyrics of 'King Of Terrors' are based on a novel by Edgar Allen Poe", says Romeo. "We had the feeling that this dark, heavy song needed dark spooky lyrics. Edgar Allen Poe is perfect for stuff like this." But the proof that this heavier sound has not completely buried the band's more melodic and epic side is documented in 'Accolade II'--the continuation of the song 'Accolade' from the 1996 album, The Divine Wings Of Tragedy; as well as the title track, divided into seven chapters with a total length of 29 minutes.

In a breathtaking musical trip through the Greek Odyssey, Symphony X have put to music such stages as the Sirens' song ('Sirens'), the conquest of Circe ('Circe (Daughter Of The Sun)'), the perilous sea journey ('Scylla And Charybdis') and finally the arrival at Ithaca ('The Fate Of The Suitors / Champion Of Ithaca'). In order to realize their visions of an exciting and deliberately harder album, Symphony X took over almost all the work on The Odyssey; the songwriting and arranging, the pre-production and the work in the studio was all firmly in the musicians' hands. "It needed a hell of a lot of energy, but it was definitely worth it", Romeo says with satisfaction. The band's seventh studio release, Paradise Lost, was released on June 26, 2007.

The guitarist of SYMPHONY X describes »ICONOCLAST« (2011) as follows: »Iconoclast« delivers a summary of our work until now and a musical statement of SYMPHONY X in the second decade of the new century.″
The album is fulfilled with hymns and classical songs, hard and furious leads, sensitive vocals and multi-faceted tracks. Heavy Metal combined with Classic Rock and Progressive Rock makes this album of SYMPHONY X a milestone that will never disappoint!

Heavily inspired by the Italian poet Dante Alighieri, the new album »Underworld« draws on the themes from Divine Comedy most notably the part on Inferno. As homage to Dante’s use of the number 3 and its multiples, the band utilizes this motif in its music either in a lyrical or melodic context. The first song on the album is a three-syllable, three-note melodic phrase, and in the verses, there are three references to three songs on the band's third album.