Trish Keenan was a woman out of time and between frequencies. In promotional and live concert photos, the Broadcast singer’s likeness was abstracted, fragmented, and awash in projection, shot through with an arsenal of visual effects that channeled the experimental art of Brion Gysin, Dora Maar, and Andy Warhol’s Exploding Plastic Inevitable. With her severe black fringe and starch white tunic, Keenan could even resemble a photo negative version of Nico. But where Nico came to resent her beauty and actively sought to subvert it, Keenan courted iconicity. By diffusing and distorting her image, Keenan became a Dale Cooper-figure for the band: an astral explorer capable of navigating and illuminating the alternate states their music sought to conjure.

Since Keenan’s passing from pneumonia in 2011, the limitless horizons that Broadcast proposed have been darkened by their singer’s absence. Any appreciation of the band, whether written in tribute or spoken among fans, is immediately asterisked by a sense of tragedy. Because so much of their music explored the spectral qualities of sound and memory, even listening to Keenan’s reverb-laden voice can take on the quality of EVP, skirting the line between haunting and haunted. Yet for a group whose best-known album is a masterpiece of death-obsession, the enduring theme of the band’s work is a rejection of finality. In a Broadcast song, new dimensions are always within reach, suggesting that sound manipulated could result in time transcended. The reissue of three collections of rarities—the new BBC Maida Vale Sessions, and two tour-only albums, Microtronics (2003) and Mother Is the Milky Way (2009)—provides a small survey of the band’s evolution from a conventional pop outfit to psych visionaries.

Like many British artists of their generation, founding members James Cargill and Trish Keenan were radicalized by what the critic Mark Fisher called “popular modernism,” the diffusion of challenging, surreal art through mass media. Part of the poignancy of the Maida Vale Sessions comes from hearing the band prove themselves on their heroes’ turf. The facilities at Maida Vale not only hosted the radio show of John Peel, from which these recordings are sourced, but the original BBC Radiophonic Workshop, which introduced the British public to electronic music on a mass scale, a history that prompted Keenan to describe the performances as an “initiation.” Maida Vale makes abundantly clear that the band passed with flying colors.

Encompassing material from 1997’s Work and NonWork compilation through 2003’s Haha Sound, the album charts their path from studious, ’60s songcraft toward their own singular sound. Had they stalled out creatively on songs like “The Note [Message From Home]” or “Come On Let’s Go,” Broadcast would have endured as some of the finest interpreters of swooning chanson and psych rock of the 1990s, a decade that wasn’t hurting for revivalists of either stripe. What distinguished them from well-observed pastiche, and what these live recordings highlight, is the dissonance and distortion that lurked at the edge of their sound, as they progressively fused psychedelic fuzz with aggressive electronic effects. The ominous piano chords that launch “Long Was the Year” land on a bed of flickering guitar feedback, while “Echo’s Answer” features a gorgeous extended outro where Keenan’s vocals recede and electric guitars duel over cinematic, ultra-processed strings. The shift from clarity to obscurity was also reflected in the band’s songwriting, as their bookish character studies were phased out in favor of nonsense poems, automatic writing, and cut-up lyrics. No one knows the answer to the questions posed by “Where Youth and Laughter Go,” but in its mesh of music box keyboards, starry-eyed lyrics, and ribbons of corroded and crystalline guitar, the band dares you to imagine.

Cold, clarion, and remote in its beauty, Keenan’s contralto is a singular instrument, an echo that never stops reverberating. One of Maida Vale’s greatest virtues is how it showcases her evolution between records. On tracks like “The Book Lovers” and “World Backwards,” Keenan belts, straining the limits of her range, an affectation that she would dial back by limiting herself to a glassy deadpan. She presents this technique most effectively on “Minim,” where her cascading sighs soar over unfurling synths, snares, and guitar, becoming elemental in the process.

Microtronics is a collection of instrumentals initially released on tour for 2003’s Haha Sound, and it expands upon that album’s interstitials and outros. Enamored with stock “library music,” the band aimed to make generic tunes in a singular way, diverse in sound but immediately recognizable as Broadcast. Tracks like “Microtronics 01” and “Microtronics 09” feature the crisp jazz you could imagine sound-tracking a David Lynch netherworld, while the comet strike synths of “Microtronics 06” and the buoyant jingle of “Microtronics 04” hold their own against Warp labelmates Autechre and early electronic composer Raymond Scott, respectively.

The acoustic fretwork and swelling strings of “Microtronics 11” point the way to the uncanny soundscapes of 2009’s Mother Is the Milky Way. By now whittled down from a five-person outfit to the duo of Cargill and Keenan, Mother plays like the band’s version of a mixtape, an audio collage that swerves wildly between the pastoral and occult. The record draws from both British folk music and British folk horror, contemplating the slippery delineation that separates prim and proper England from its pagan past. “In Here the World Begins” cuts through a squall of children’s recorder to offer a hypnotic, elliptical dirge about accessing a “dream within a dream,” while “I’m Just a Person in This Roomy Verse” features one of the band’s loveliest melodies, intruded by deranged babbling and demonic whispers. Having largely forsaken sampling in favor of recreating the sounds of the past on their own, Mother points to a thrilling, largely unexplored direction for the band: a universe where Vashti Bunyan meets Nurse With Wound, of dappled sunshine and bottomless darkness.

In late 2011, after Keenan’s passing, Cargill confirmed there was enough recorded material in the vault to fashion a new Broadcast album. As of now, it has yet to be released. Cargill has since made an excellent tribute to his creative and romantic partner with former bandmates as Children of Alice, and unreleased tracks and demos have trickled out over the years, often on Keenan’s birthday. Taken together, these three reissues make up one of the most substantial reminders of the band’s power, even in moments of relatively low-stakes creativity. They offer a rejoinder not to regard Keenan as a ghost who haunts the work but as an enduring presence who activates it with every listen.