The increasing popularity of "funky" or "soul" jazz among both musicians and fans is the most important jazz trend of recent years. In part, it is a reaction against the emotional detachment, intellectualism and classical orientation of men like Lennie Tristano and John Lewis. Its essence, though, is a rededication to the roots of jazz: the blues, Negro church music, and a strong beat.

Soul jazz is not a fad, like the Bossa Nova. Rather, it represents a thorough-going revolution which has influenced even popular music, thanks to Ray Charles.

If Charles is the popularizer of soul jazz, the intellectual leaders of the movement is Horace Silver, a slight, 35-year-old pianist and composer from (of all places) Norwalk, Conn. Silver, came to New York with Stan Getz in 1950, played with Art Blakey's Jazz Messengers for a few years, and finally formed his own quintet in 1956.

Silver is a favorite of jazz buffs; one reason is the care he takes in making recordings. He never rushes into a record date; instead, he waits until he has built up a small repertoire of original tunes which are rehearsed and polished by the quintet in nightclubs and concerts until they are ready to be committed to wax. Silver seldom makes a record--one or two a year at most--but when he does, it's generally a very good one.

The latest release by the Horace Silver Quintet, The Tokyo Blues (Blue Note (4110), consists, like most of their other albums, of tunes which Silver wrote especially for the group. He is one of the leading jazz composers; some of his compositions (Moanin', Doodlin', and The Preacher, to name three) have become jazz standards.

The inspiration for The Tokyo Blues was the quintet's recent tour of Japan. All the number have a vaguely Japanese air about them, but essentially they are down-to-earth American. Silver's percussive, exciting piano is accented by the tight playing of the group and written bridges between solos, a favorite Silver device, give the music unity and discipline. The title tune and the rhythmic Too Much Sake are the best numbers on the record, but all of them are good.