In 1969, guitarist Larry Coryell released perhaps the first-ever acoustic jazz-rock guitar duet album with John McLaughlin.
During breaks from his lifetime career of re-forming his band Mahavishnu Orchestra, John McLaughlin put in many diverse appearances as a sideman. This album was a pinnacle. Don't let me mislead you by mentioning McLaughlin's name first; this was definitely Larry's album.
Essentially this was a "friendly duel" between the two accomplished guitarists. Both were firmly entrenched in "acoustic" periods for this outing, though each also has done strong electric work at other times. Coryell's later band "The Eleventh House" best showcased his electric side; that group featured a snappy, insistent Alphonse Mouzon on drums.
The pairing of Coryell and McLaughlin was delightful, each trying to outdo the other with jazzy, fluid lines. But the duo was probably also destined to self-destrruct, so seemingly different were the 2 personalities. "Spaces" set the bar so high that Coryell appears to have spent the bulk of his career since its release trying to top it.