Answer the question at the end by quoting:

King's X is an American rock band that combines progressive metal, funk and soul with vocal arrangements influenced by gospel, blues, and British Invasion rock groups. The band's lyrics are largely based on the members' struggles with religion and self-acceptance. King's X was ranked No. 83 on VH1's 100 Greatest Artists of Hard Rock.
The group released its debut album as King's X, entitled Out of the Silent Planet, in 1988. Despite being hailed by music critics, the album did not fare well commercially, peaking at No. 144 on the Billboard album charts. The songs "King" and "Shot of Love" were released as singles, but failed to garner much attention. The album derives its name from the C. S. Lewis novel Out of the Silent Planet. This appears to be the band's first of multiple references to the British author. In 1989, the band released Gretchen Goes to Nebraska. Considered by many fans to be their landmark album and most creative period, the album fared only slightly better from a commercial standpoint than Out of the Silent Planet. The band played with a wide variety of acts while touring in support of it, including Anthrax, Suicidal Tendencies, M.O.D., Living Colour, Billy Squier and Blue Murder. The album contains many fan favorites such as "Summerland", "Mission", and "The Burning Down". The song "The Difference (In the Garden of St. Anne's-on-the-Hill)" appears to be another C.S. Lewis reference, this time to a scene in the book That Hideous Strength, third and final installment of the "science-fiction" trilogy begun by Out of the Silent Planet. The song "Pleiades" is credited by Ty Tabor as being the genesis of the King's X sound when he presented the demo to the other band members a few years earlier. Significantly, the song "Over My Head" received moderate airplay on MTV and radio. The increase in exposure would prove beneficial when the band released their third album, Faith Hope Love, in late 1990. It was the group's first album to crack the U.S. Top 100, with the help of the successful single "It's Love". Another track, the funk-rock "We Were Born to Be Loved", enjoyed a long life on Late Show with David Letterman as a commercial bumper instrumental favorite of Paul Shaffer's CBS Orchestra. King's X was featured in the February 1991 issue of Rolling Stone (RS598). Still, with major mainstream success continuously eluding them, King's X began questioning Sam Taylor's management vision for the group. The band landed the opening slot for Iron Maiden in Europe on their No Prayer for the Dying tour in late 1990, and AC/DC in the U.S. and Europe for the first half of 1991. They also toured with Living Colour, themselves near the peak of their popularity. In the middle of that year, their song "Junior's Gone Wild" appeared on the soundtrack to the movie Bill & Ted's Bogus Journey.

was it a success

their landmark album and most creative period, the album fared only slightly better

Answer the question at the end by quoting:

Symphony X is an American progressive metal band from Middletown, New Jersey. Founded in 1994, the band consists of guitarist Michael Romeo, keyboardist Michael Pinnella, drummer Jason Rullo, lead vocalist Russell Allen and bassist Michael Lepond. They achieved some commercial success with the 2007 album Paradise Lost and the 2011 album Iconoclast, which reached number 76 on the Billboard 200. Romeo explained the band's name in a 2008 interview; "So, you know, the music we were coming up with had the keyboard thing and the guitar, and some classical elements, so the word 'Symphony' came up and, so the dramatic thing, you know?
The band is working on releasing a second fan club CD. Michael Romeo said it will be another collection of demo tunes and other rare material, and may also include a bit of content created just for the release, along the lines of MJR's Star Wars tune on the first fan club CD, Rarities and Demos, which has since sold out of its first pressing. SXW, the band's revamped fan club, has relaunched and is now active. The band began recording the drum tracks for the new album on September 9, 2014, and planned to release the complete recording by the spring of 2015. Michael Lepond stated they had ten songs written and that the album would contain either nine or all ten of them. He also stated all lyrics and instrumental tracks were composed and ready to be brought together, and that the album would be less heavy than Iconoclast: "If I had to compare, I would say that it's a combination of The Odyssey and Paradise Lost -- something in there. It has a lot of classic Symphony X elements in it, which I think a lot of our fans were missing for a few years. So I think our fans will really like this one. It really just focuses on solid songwriting." As of December 11, 2014, recording of the drums, lead vocals, rhythm guitar, and bass were complete. With the keyboards, guitar solos, background vocals, and some miscellaneous odds and ends being done in the coming weeks. On April 10, 2015 the band announced the mixing and mastering of the new album was complete. On May 18, 2015, the band announced the title of the album would be titled Underworld, and a release date of July 24, 2015. The first single from the album, "Nevermore", premiered on May 22, 2015. The band released the second single, "Without You", on June 19, 2015, and was made available for digital download. According to singer Russell Allen, the band entered a short hiatus during 2017 in which they did not perform, due in part to his commitment to Adrenaline Mob, although it was announced during a January 2018 interview with Metal Nation that the band had plans to get together in the following months and begin writing a follow up to Underworld. On July 14, 2017, Adrenaline Mob was involved in a serious vehicular accident, which resulted in severe injuries for Allen and two deaths.

When was the album released?
a release date of July 24, 2015.