Dedicated to heartfelt emotion in his music and candor on stage and off, the bassist-composer Charles Mingus was not one to mince words - and his directness has been restored to print on the recently reissued ''Music Written for Monterey, 1965: Not Heard...Played in its Entirety, at U.C.L.A.''
Onstage at U.C.L.A. in 1965, Mingus sent half his band backstage to practice in the middle of the set. Earlier, he admitted that he goofed and entered a tune in the wrong place. But this stage action would not have been reason by itself to reissue the album (East Coasting Records, P.O. Box 866, Ansonia Station, New York, N.Y. 10023). More important is the chance to hear otherwise unavailable Mingus compositions - ''They Trespass the Land of the Sacred Sioux,'' ''Don't Let It Happen Here'' and ''The Arts of Tatum and Freddy Webster'' - and arrangements of ''Muscrat Ramble'' and a suite of be-bop tunes, ''Ode to Bird and Dizzy.''
The title tells only half the album's story. After the Mingus octet's set was cut to half an hour at the 1965 Monterey Jazz Festival, the group played the music it had prepared for Monterey in a full-length concert at U.C.L.A. a week later, on Sept. 25, 1965. There, the 87-minute show was taped by U.C.L.A.'s recording and engineering staff. Mingus's own label pressed 200 copies of the two-record set in 1966, then ran out of money, and the original master tapes were destroyed when Capitol studios cleaned out its vaults in 1971.
Fred Cohen of the Jazz Record Center and the composer's widow, Susan Mingus, have now supervised a reissue of the set, re-recorded and remastered from a mint-condition copy of the original LP's. The reissue also includes a seven-inch disk with one piece, ''They Trespass the Land of the Sacred Sioux,'' from the short set the Mingus octet played at Monterey. The monaural sound is still clear, although it preserves the vagaries of the original recording, and the performance it documents is a fascinating bit of jazz history.
Among his other achievements, Mingus was a determined pedagogue, eager to remind his audiences that jazz is simultaneously a body of tradition and an art of the moment. He taught the music to his sidemen by ear - without written parts - and called his bands Jazz Workshops. Particularly in the 1960's, the bands lived up to their name by presenting concerts as works-in-progress. Mingus would start and stop the band, advise and exhort soloists, and do anything else he deemed necessary to push the group to the proper pitch of high-adrenaline soulfulness, letting audiences in on the process as a conceptual artist might.
At U.C.L.A., playing complex, fairly new pieces, there were bumpy spots. Mingus and the drummer Dannie Richmond come in too early on the ending of ''Meditation on Inner Peace,'' a slow, dignified vamp piece with an eloquent bowed bass soliloquy. Next, the octet twice tried the chorale-like opening of ''Once Upon a Time, There Was a Holding Corporation Called Old America,'' an ambitious Mingus tone poem.
Mingus demonstrated the introduction on piano, but the band couldn't get the hang of it, so most of the octet's brass section - the trumpeter- flugelhornist Jimmy Owens, the trumpeter Hobart Dotson, the French hornist Julius Watkins and the tuba player Howard Johnson - was banished backstage to practice. While they did, Mingus, Mr. Richmond, the saxophonist Charles McPherson and the trumpeter Lonnie Hillyer played ''Ode to Bird and Dizzy,'' which incorporates Tadd Dameron's ''Hot House,'' Dizzy Gillespie's ''Night in Tunisia'' and other be-bop standbys.
Things went a little more smoothly from then on; the octet had already burnished some of its arrangements in a stint at the Village Gate. The mostly brass lineup was an unusual one for a Mingus band, and the arrangements revel in the warmth of brass-chorale chords. The sultry, ultra-slow-drag ''They Trespass the Land of the Sacred Sioux,'' got a reverent reading at U.C.L.A. - less mercurial than the Monterey version from a week earlier but still featuring Mr. McPherson's rippling obbligatos and Mr. Watkins's long-sustained final note. And when it was finally heard, ''Once Upon a Time. . .'' turned out to be a jaunty, shifty waltz. (It was later recorded under the title ''Shoes of the Fisherman's Wife.'')
''The Arts of Tatum and Freddy Webster,'' including a reharmonized section of Dvorak's ''Humoresque'' in tribute to Art Tatum's jazzed-up version, stumbled a bit. But ''Don't Be Afraid, the Clown's Afraid Too'' is bumptious and tender, and ''Muscrat Ramble'' finds a middle ground between New Orleans improvisation and the more thoroughly arranged style of Mingus's small groups, while still letting the soloists cut loose. In ''Don't Let It Happen Here'' the bandleader recites a poem over sustained chords a la Copland, then pushes the band into a fast theme distantly related to Mingus's ''Haitian Fight Song''; there's also a torchy flugelhorn solo by Jimmy Owens.
Although ''Music Written for Monterey'' has been out-of-print for 18 years, it still sounds modern. Current avant-gutbucket bands were obviously inspired by Mingus's sense of history, his large-scale structures, and the drive and emotionality of his bass playing and his band sound, which remained distinctive through lineup after lineup. Warts and all, Mingus's music - like his concerts - held nothing back
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