Robin Trower: For Earth Below 50th Anniversary Edition (Chrysalis. 4 CDs). Back in 1975, when this album was originally released, there was substantial pressure on Trower and the rest of his trio. Trower’s first solo album, “Twice Removed from Yesterday,” issued after he left a four-year stint with Procol Harum, re-introduced Trower as a psychedelic blues-rock guitar god in the image of Jimi Hendrix. That Hendrix influence can be heard in this album’s opener, “Shame the Devil,” and “Gonna Be More Suspicious.” The second album was the critical and commercial success “Bridge of Sighs.”

This 50th anniversary edition of his third album includes a new remaster of the original 1975 mix, plus a new stereo mix of the eight-track album. The third disc of 15 tracks contains outtakes and remixes, six never-before released. The fourth disc is an 80-minute, March 1975 concert in Los Angeles.

By the way, Trower is still going strong and his current tour brings him to Aura in Portland, Maine, tomorrow night (Friday, June 27).

The trio’s original drummer, Reg Isadore, had clashed with singer/bassist James Dewer. His replacement was Bill Lordan from Sly & The Family Stone, Lordan infused a funkiness to the trio’s sound, evident in the opening rocker “Shame the Devil” and the upbeat “Alethea” and the wah-wah filled “Confessin’ Midnight.” Lordan also drives the beat on the soulful “Gonna Be More Suspicious.” Dewer’s vocals are fine throughout and a perfect match for Trower’s liquid guitar playing.

Trower recorded the sessions at Los Angeles’ Record Plant instead of in the United Kingdom. Producer Matthew Fisher, also ex-Procol Harum, returned from “Bridge of Sighs.”

“Shame the Devil” is funky blues-rock, with a layer of psychedelic fuzz on top. The bluesy “It’s Only Money” is slower, before “Confessin’ Midnight” returns to funk with a growling vocal. “Fine Day” features warm, fuzzy guitar tones as it dips into R&B. “Alethea” has the album’s best groove and invites another comparison to Hendrix. “A Tale Untold” is more funk before its languid ending. The stellar “Gonna Be More Suspicious” is in funky Hendrix style. The album then closes with the spacey title track, “For Earth Below,” which opens with bird sounds.

 Disc three has four unreleased vocal outtakes, led by “It’s Only Money” and the non-album “Happy,” a nice song that makes its first official appearance. Also new is a 17:46-long instrumental jam from September 1974. The rest of the disc is previously available BBC recordings, including seven minutes of a Trower interview, joined by four of the new album’s songs on the Jan. 28, 1975 “Top of the Pops.” Three more, including “Alethea,” are from the next day’s “BBC Live in Concert.”

Disc four is a previous unavailable, professionally recorded 13-song concert from LA’s Shrine Auditorium & Expo Hall on March 16, 1975. The terrific show opens with two songs from “Bridge of Sighs.” In all, it has six from that album, four from the new album and three from the first album. Six tracks exceed seven minutes, including a 9:46 version of “Daydream” that has a dazzling Trower solo. “Lady Love” and the very Hendrix-styled “Too Rolling Stoned” also standout. The closing “Rock Me Baby” and “The Fool and Me” are combustible.

The discs are contained in a paperback-sized, 20-page hardcover book with newly written liner notes by journalist David Sinclair. Trower, quoted in the notes, gives a candid appraisal of the album, saying: “It’s not one of my favorites. There are quite a few of my albums that I prefer, that I’m prouder of… You make albums hoping that somebody’s going to think it’s great. And I do think there’s some great tracks on it. “Gonna Be More Suspicious,” “Shame the Devil” and the track “For Earth Below” I really love. It’s a song that I did live for many years that I used to love playing.” Grade: original album A-; box set A