Blues Fest Injects Soul Into Event : Pop music: Performers-- including Dr. John, Fabulous Thunderbirds and Buddy Guy--will be spread out over two days in Long Beach.

This weekend’s 16th annual Long Beach Blues Festival offers a compelling variety of blues stylists, notable for the presence of several R&B;, jump blues pioneers as well as traditional acoustic-blues performers and soul shouters. Of course, there also will be a good number of Chicago-style guitar slingers at the KLON-FM-sponsored event, which runs today and Sunday at Cal State Long Beach.

Highlights of today’s lineup:

* Pianist Jay McShann (scheduled to go on at 11:45 a.m.) is perhaps best-known as the man who featured a very young Charlie Parker in one of his early-’40s big bands, but McShann is an excellent instrumentalist, arranger and bandleader in his own right. Originally a boogie-woogie stylist in the vein of Meade Lux Lewis, McShann later came to be known for his Count Basie-inspired, hard-swinging charts and for leading one of he finest bands to come out of the Kansas City tradition.

* Blues shouter Jimmy Witherspoon (noon) is the last living member of an exclusive club that in its heyday included Big Joe Turner, Wynonie Harris, Roy Brown and Eddie (Cleanhead) Vinson among its elite. Witherspoon’s once gracefully powerful pipes are not the magnificent instrument of yesteryear, but as the last original practitioner of a near-dead art form, this legendary baritone is not to be missed.

* Floyd Dixon (11:30 a.m.) is a singer-pianist in the Amos Milburn mode, and a longtime West Coast favorite who also, like so many American blues artists, is revered overseas. The Texas-born performer is best known for his 1954 hit “Hey Bartender,” the king of all drinking songs, which was re-popularized by the Blues Brothers in the early ‘80s.

Arrive early if you hope to see McShann, Witherspoon or Dixon--each is allotted just 15 minutes in back-to-back sets.

* The Johnny Otis Show (1:20 p.m.) is a mini-festival unto itself, comprising a number of guests who could headline a show on their own. Appearing with bandleader Otis--who also serves as vibraphonist, drummer, singer, composer, radio personality and musical preservationist--will be Big Jay McNeely, the hard-honkin’ wild man of the tenor sax; Lowell Fulson, the L.A.-based blues singer-guitarist who scored a number of R&B; hits in the ‘50s and gave Ray Charles his start in show biz, and Mary Hopkins, a lesser-known but extremely powerful gospel-inflected R&B; singer.

Higher-profile acts playing Saturday include Charles Brown (12:20 p.m.), Dr. John (2:55 p.m.), Otis Rush (4:05 p.m.) and Buddy Guy (5:05 p.m.).

Sunday’s roster serves up only half the number of acts featured Saturday but is distinguished by appearances by the Stax Revue and Brownie McGhee. It also boasts the Fabulous Thunderbirds (1:50 p.m.), whose lineup now includes Anaheim guitarist David (Kid) Ramos, a former member of the James Harman Band.

* The Stax Revue (3:10 p.m.) features Booker T. & the MG’s with the Memphis Horns, Eddie Floyd, Rufus Thomas and Mavis Staples (the sultry-toned secret weapon of the Staple Singers, who ranks along with Aretha Franklin and Etta James as being one of soul music’s premier stylists.)

* Brownie McGhee (12:30 p.m.), recognized for his longtime partnership with late blues harpist Sonny Terry, is an old-time songster equally adept at the blues and folk music. The storyteller supreme was originally billed as “Blind Boy Fuller No. 2” much to his understandable chagrin, but this highly intelligent and personable performer is a walking, breathing, singing encyclopedia of American musical traditions, with a simple but effective acoustic-guitar style and smoky, lonesome voice.

* KLON’s 16th Annual Long Beach Blues Festival will be held today and Sunday on the north athletic field of Cal State Long Beach, 1250 N. Bellflower Blvd., Long Beach. Music starts both days at 10 a.m. $28. No alcohol, cameras, tape recorders, barbecue grills, umbrellas, glass or metal containers or pets are allowed. (310) 985-1686.