Several years ago I spotted Gary Boyle playing in a local jazz festival, a free event that demonstrated his commitment to his art as much as emphasising how times change. Now it's difficult to find even a proper website for the jazz rock guitarist who in the sixties backed Dusty Springfield and who is now touching 70.

Back in 1973 Boyle had formed Isotope and produced a series of excellent fusion albums until the band imploded in 1976. For a period they were highly regarded. Many punters thought they were Mahavishnu-lite but they didn't have a violinist and were arguably more accessible than the McLaughlin-led fusionists. And they won a few high placings in the annual Melody Maker poll.

Joining Boyle on the debut Isotope in 1974 were fusion stalwarts Nigel Morris (drums) who had played with Boyle in Stomu Yamashta's band, Brian Miller (keys) and Jeff Clyne (ex-Nucleus) .

From the opener 'Then There Were Four', the band's trademark electric piano grit and fluid guitar licks are all in place but elsewhere they could be a funky combo when required ('Do The Business', 'Oh Little Fat Man').

Isotope emerged in an age when Dutch band Focus were in the ascendancy and at times - in the fluid juxtaposition of keyboards and guitar - they recall that outfit. And they weren't that far removed from those other Dutch jazz rockers Trace or Solution, although a tad more rocky. On 'Honkey Donkey', the band also evoke progsters Camel. ***½

For the band' s second album Illusion, Soft Machine vet Hugh Hopper came in on bass whilst Laurence Scott replaced Miller on keys. Family's multi-instrumentalist Poli Palmer produced and renewed a previous acquaintance with Boyle when in the band The Eclection.

Stylistically there wasn't a lot of difference from the debut, a mix of frenetic jazz rock workouts ('Illusion', 'E-Dorian') and simpler funk ('Rangoon Creeper') but the album contained more Gary Boyle composition which does take it more into sub-Mahavishnu territory. ***

The band's final album Deep End (1975) is arguably their funkiest and finest. This time, only Boyle and Morris remained from the original line-up and in came Frank Roberts (keys) aided by Zoe Kronberger and Dan K Brown on bass. Robin Lumley, cousin of Joanna, produced and was also a member of jazz rockers Brand X - with Phil Collins - in the seventies.

The opener 'Mr. M's Picture' might have graced a later Camel album and would appeal to fans of that band, although without Andy Lattimer's sweeping guitar. Boyle was always very much in fluid fusion-mode. 'Crunch Cake', 'Pipe Dream' and 'Fonebone' up the funk quotient whilst 'Black Sand' evokes prime-time Weather Report. ****

The lack of bonuses on these reissues suggest a lack of outtakes (with the exception of some 2001 remixes on 'Deep End') but there are useful sleeve notes to each release. Any BBC session stuff was nicely showcased by Hux Records on an album in 2004 which is also worth investigating to complete this story along with Boyle's late seventies solo albums 'The Dancer' and 'Electric Glide' .

Isotope came to a halt after management and label problems, and on the verge of punk their intense and musicianly approach went - sadly - somewhat out of fashion. Esoteric have done a good job of resurrecting these releases and a re-evaluation is long overdue.

Review by David Randall