Long-running British group Amp have occupied many sonic territories since first surfacing during the early '90s, including space rock, dream pop, ambient drone, and trip-hop. The group's sole constant member has been Richard F. Walker (aka Richard Amp), a musician, engineer, illustrator, and designer who has also released solo material credited to A.M.P. Studio. Besides Walker, the group's other core member has been French vocalist Karine Charff, who has been with Amp since their first proper album. Other contributors to the group, who have referred to themselves as "Trans-European Esoterrorists," have included Matt Elliott (Third Eye Foundation), Matt Jones (Crescent), and Robert Hampson (Loop, Main). Equally interested in the textural aspects of music as well as songwriting, Amp have always defied conventions with their recordings and live performances. Their work has incorporated numerous experimental techniques as well as influences from pop, folk, and electronic music, resulting in largely improvised music that ranges from lengthy, feedback-drenched soundscapes to ethereal electropop songs. Amp often utilize field recordings and nature sounds in their work, lending to its abstract, environmental feel.

Richard Walker first became interested in experimenting with sounds after hearing a BBC sound effects record sometime during the late '70s. Eventually, he worked with David Pearce (later of Bristol-based group Flying Saucer Attack) on projects such as the Secret Garden and the Distance. His first release as Amp was a self-released 1992 cassette titled Green Sky Blue Tree, which featured spoken word passages over ethereal soundscapes, as well as fluttering saxophone courtesy of Ray Dickaty, later of Moonshake and Spiritualized, among many other groups. By the time Amp made their vinyl debut in 1995, with the single "Remember?," their sound had shifted to hypnotic psych-rock. Debut album Sirènes followed in 1996, issued in the U.K. by Wurlitzer Jukebox and Matt Elliott's label Linda's Strange Vacation, and in the United States by the short-lived Petrol Records. Two further singles appeared on Wurlitzer Jukebox that year, in addition to another 7" on Enraptured, which contained an Amp/Third Eye Foundation collaboration. The following year, Enraptured released Passé Présent, which compiled the tracks from Amp's 7" releases, in addition to previously unreleased material. Several other Amp releases appeared in 1997, including Astralmoonbeamprojections (their debut for Kranky), Perception (an ambient double CD released as part of Darla's Bliss Out series), and Heart Soul Dissolves (also on Darla).

In 1998, Amp shared a split EP with Michigan space rock duo Windy Carl, issued by the latter's Blue Flea imprint. Their second album for Kranky, Stenorette, appeared later in the year, and contained some of their most accessible work yet. After releasing a few albums and singles credited to A.M.P. Studio, Amp made their proper return with Saint Cecilia Sinsemilla, issued by Space Age Recordings in 2001, followed by L'Amour Invisible in 2002. After another break, Amp returned in 2005 with the Very Friendly-issued Us, a more accessible album that featured early member Dickaty, as well as a self-released ambient double CD-R titled Transmissions: Phase 1. All of Yesterday Tomorrow, an extensive three-CD rarities collection, was issued by RROOPP in 2007. Since then, Amp have released several collections of live performances and non-album material through their own Ampbase.net label/website, usually as limited CD-R or digital releases. The properly distributed CD Q Factors (A Mixtape), containing unreleased tracks and remixes dating back to 2000, appeared in 2017. ~ Paul Simpson, Rovi