FEW DANCE COMPANIES offer as wide a spectrum of style and tones in one night's repertory as does the Alvin Ailey American Dance Theater. The company is known for its unique blend of ballet, modern and jazz dance, and the format of this week's Boston performances--in which any four of 15 pieces may be presented on a given night--shows up this range to good advantage.

In contrast to most other American dance companies where the movement itself is the most important element of the performance. Ailey tries to synthesize other elements in his theater--memorable and often modern plot and characters, music that can stand on its own merit, and sets that linger in the mind. The musical repertory is as diverse as the dance styles, adding Miles Davis and the group Earth, Wind and Fire to the more traditional Mendelssohn. Bach and Ravel "Revelations," set to chotal Negro spirituals, glorifies the Black experience through folk dancing and Biblical motifs.

Tuesday's premiere performance showed the versatility of the troupe's technique in four markedly different pieces. The zany, humorous "Fontessa and Friends" opened the show with music by the Modern Jazz Quartet. Scott Joplin, Khachaturian, James P. Johnson and Linda Clifford. This lively spoof on ballet and love affairs has a definite plot Fontessa (April Brown) paces around in an evening gown, languishing for The Man, a strong, macho hunk danced by Keith McDaniel. Meanwhile, Ragtime (Ralph Glenmore), a cool Black dude reminiscent of Ben Vereen, laughs at lovers, audience and himself. He turns to the back of the stage, produces "magical" effects on the lighting, and waits for the audience to applaud.

Throughout the dance six male clowns, dressed in white tutus, imitate a corps de ballet of Swan Lake and inelegantly entertain and interrupt Fontessa. Ragtime and The Man with amusing burlesques. The piece's success rides more on its dramatic and humorous aspects than inherent strengths in the dance. Towards the end Fontessa enters the stage in a sequined silver bikint to the song "If my friends could see me now." At one point one almost expects Ragtime to open his mouth and begin talking--certainly a radical departure from any traditional dance form.

Alvin Ailey's latest composition, "Satyriade," set to music by Maurice Ravel, provides a sharp contrast. In this piece, the merits of the performance rest more on the superb choreography and the technical success of the dancers than on any plot. Beautifully danced by three couples with the women dressed as Greek nymphs and the men as the lecherous mythical satyrs, the dance stresses the pas de deux structure, with the different pairs alternating on stage. Although their movements and gestures are based on ballet, the overall quality is much more free and unrestrained and possesses a fluid, electric energy. Orange, yellow and pink gowns, bare feet and a haunting set of tall, dark trees looming over the stage all contribute to a mesmerizing effect.

Ailey's choreography has all three pairs dance together for the last few minutes, mirroring each other's movements, creating a slight drop in energy and intensity from the duets' earlier turns, jumps and lifts. On opening night the dancers seemed to concentratrate a little too much on technique; then emotions barely seeped through the almost flawless dancing.

THE BEST of the opening night pieces. "Treading," probably rates with Ailey's popular "Revelations" or "Memoria." Choreographed by Eliza Monte with music by Steve Reich. "Treading" was danced, or rather synthesized, by Sarita Allen and Kevin Brown. The abstract work moves to music reminiscent of African drumbeats in a modern electric synthesizer or a xylophone. Slowly, the two bodies stretch, plie, arch and contract together and apart as the man and woman unite. The technical strength of the two dancers is apparent every moment, as they balance on one leg or develop their legs into high back arabesques.

Brown has a beautiful line and moves his muscles in a cat-like stretching manner that rivets one's eyes to his flowing muscles. Similarly, Allen creates electric currents through her body without appearing to exert any effort. The beige unitards with blotches of black and red on the front merge dancers into the black set and gold lights. As the dance progresses we see them less as physical beings than as conglomerations of contracting muscles making waves. The concentrated experience of these two bodies rolling on the floor--as if it were the most natural motion possible--leaves the audience motionless for a few minutes after the work has ended.

The effects of the electrifying music and ethereal dancers becoming one is phenomenal; these 15 minutes alone are a reason to see the Alvin Ailey Company.

"Stack-Up," though not as intense an experience as "Treading," is certainly not anti-climactic. Choreographed to music by Earth, Wind and Fire. Two Tons of Fun, Fearless Four, Alphonze Mouson and Grover Washington Jr., this jazzy piece features an ensemble of sixteen dancers discoing their hips to flashy music in flashy colors. Different gangs are quartered off--the punks, the sleazies, and the cools. The dancing here is the main event; the groups are unified internally, and the dancers shift styles with ease as the music alternates between disco and saxophone-blues. Throughout the shifts, there is a constant beat that makes one want to get up and dance.

Alvin Ailey is one of the few modern dance companies which does not get lost in attempts at "abstraction" and "free expression." Their adherence to basic dance roots and training, together with their use of modern life and modern music, puts them among the most accessible and exciting American companies now dancing.