Egmont Sonderling, head of the company that owns radio station WOL here, defended the station's disc jockeys yesterday against charges that they took money from concert promoters to publicize local concerts.

Sonderling, ending his two days of testimony before a Federal Communications Commission that William E. Washington, a music promoter here who leveled the charges, had failed to support them with hard evidence.

The board chairman of Sonderling Broadcasting Corp. added, during interviews afterward, that he felt the FCC lawyers "have been much tougher on me than on the complaining witnesses," including Washington.

He cited Washington's statement that WOL disc jockeys had guaranteed the success of a concert featuring the Earth, Wind and Fire singing group last year by "playing the hell out of" the group's records after Washington had agreed under pressure to pay the disc jockeys $14,000 to assure the records would be aired.

Sounderling said that Washington had failed to submit solid proof that the group's records had been aired excessively, and that the FCC lawyers had neglected to ask him for it.

The Miami, Fla., bassed corporation's head also pointed in the hearing to conflicts in testimony by Washington and by a rival local promoter, Jack Boyle of Cellar Door Concerts, Inc., about the $14,000 payment.

Sonderling testified that letters last spring from a lawyer for Washington and Boyle, complaining about the WOL disc jockeys' activities, amounted to "implied extortion" to force sale of the station to the two promoters.

Sonderling testified that his company had adopted policy changes last spring to prevent WOL, disc jockeys from promoting or excessively publicizing concerts. Some sources have said that the disc jockeys have publicized concerts staged by their own promotion venture, DJ Productions - an allegation that attorneys for DJ Productions have denied.

Teddy Powell, a veteran concert promoter who testified after Sonderling, said promotion of rock and other popular-music concerts by disc jockeys was extensive in this country. In his view, said Powell, "a disc jockey should be a disc jockey, and a promoter should be a promoter."

Powell said a disc jockey like WOL's Melvin Edwards, identified previously as president of DJ Productions, had advantages over a promoter like himself in lining up music groups because the disc jockey could "get better air time" to publicize concerts and had "the weight of the radio station" on his side.

Powell said "air play" - broadcasting of a music group's records - accounted for 90 per cent of the group's chances for success. "You can be bad," he quipped, "but if you get enough air play you become good."