The 25th Newport Jazz Festival got underway Friday night, beginning 10 jammed days of events that span the jazz spectrum.

The silver anniversary of the well-known festival is shaping up as one of the most commercially successful ever held, according to a spokesman. Some added interest has resulted from the all-star White House jazz concert a week ago, with President Carter in enthusiastic attendance. That concert drew an unusual and welcome amount of publicity to jazz.

"The White House concert didn't take the edge off the festival, it enhanced it, it deified it," the spokesman said.

Sarah Vaughan led off the festival Friday night to an enthusiastic reception on a double-bill with the Thad Jones-Me Lewis Orchestra. On Saturday night Ella Fitzgerald brought the house down at Carnegie Hall with a generous concert of old favorites and some new material.

A midnight concert Saturday night paired two practitioners of jazz at its most challenging-saxophonist Ornette Coleman and his Prime Time group, and pianist Cecil Taylor.

Last night tenor saxophonist Sonny Rollins and his quintet were featured with the McCoy Tyner Sextet. Later in the evening, Betty Carter performed delightfully on a bop-oriented program that also featured the Dexter Gordon quartet and the Max Roach quintet.

Highlights of the week ahead include an evening at the Roseland Ballroom with the Count Basie orchestra; "A Salute to the American Song" with Mel Torme, Stan Getz and Gerry Mulligan; a piano and guitar evening featuring Bill Evans, Mary Lou Williams and Larry Coryell; Chick Corea with a 13-piece orchestra: Stan Kenton and his band; blue singer Alberta Hunter and the "loft" jazz of the Sam Rivers Quartet.

The festival winds up Sunday with some free street fair jazz in New York City and a 12-hour big-band extravaganza out in Saratoga Springs that features the orchestras of Count Basie, Mercer Ellington, Woody Herman, Stan Kenton, Buddy Rich and an all-star outfit that goes under the name of the New York Jazz Repertory Company.

As one of the most widely dispersed Newport Festivals ever held, many of its major concerts are being held at either Carnegie Hall or Lincoln Center. But weekend events are taking place in Saratoga and in Waterloo Village, in Stanhope, N.J.

There was also events in other Manhattan locations, including a jazz evening on the Staten Island Ferry.

The Newport Jazz Festival formerly took place in Newport, R.I., from whence it got its name. Founded in 1954, it has presented virtually every artist whose name can be associated with the art of jazz and is considered the premiere showcase in its field.

The unruliness of the audiences in 1969, when Newport impresario George Wein experimented with introducing rock into the festival, caused the town fathers of Newport to expel the festival and it moved to New York City where it has been ever since.