JAMES EARL Jones doesn't just speak. Sonorous and deep, his voice resounds, a foghorn in the midst of punier tones. Imagine him as a small boy in Arkabutla, Miss., talking to the mules in a voice that could have come from the mouth of Moses.

"My father, who also has this voice, said it was because we were farm kids who were never told to hush up because the neighbors might hear us. Calling animals and so forth you stretch your voice."

He sat in the dressing room at the Warner Theatre that Yul Brynner decorated brown. It is the same dressing room he shared last year with Christopher Plummer when they were in "Othello."

That was not a happy time for Jones. He was having a serious disagreement with his then-director, Peter Coe, who he felt had made "a mess" of the play, and his own acting was suffering as a result. A black cloud of gloom and anxiety had settled around his head.

This year Jones is smiling. He is passionate about the play he is touring in, " 'Master Harold' . . . and the boys," which opened last night at the Warner. He has also become a father for the first time at age 52. His wife, actress Cecilia Hart, and 4-month-old Flynn Earl ("not to be confused with Errol") have joined him here after a frustrating separation while the play was in Cleveland, and his joy at having them with him is as bounteous as a Christmas morning's.

In a career spanning more than 25 years, Jones has proved to be not only an extraordinary actor, but a performer without a pigeonhole. He began acting in the avant-garde of the 1950s; he made his name and first fame with "The Great White Hope"; his reputation solidified with Shakespeare and arresting new plays that have not always been commercial or critical hits.

But whatever he does, be it King Lear or the voice of Darth Vader, Jones is a presence to be reckoned with. He has a large, round face, eyes masked with wire-rimmed glasses, and a modest, gently curving, vest-covered paunch that adds to his solidity. When he smiles, his whole face smiles; when he frowns, the thunder of Hades sounds in the distance. He is moody, gentle, difficult, generous--an artist who keeps on trying.

He did not really have The Voice as a child, he said, because he didn't do much talking. He had a terrible stutter. The other kids laughed at him when he was forced to read from the Bible in church. "You couldn't tell what kind of voice I had," he said. "When I got it back together again, when I gained the power of speech, I did have one high school professor who said I had an interesting voice that I should do something with. As a substitute for talking, to express myself between the ages of 5 and 15 I wrote poetry, and one of the ways of working on my stuttering was to read the poems, so somehow poetry became a part of my re-learning to talk."

"You should hear him at home now," said his wife, imitating a tiny, shrill voice. "He talks in this little screechy voice." Like the baby. Jones grinned, almost sheepishly. "When he's on my chest he likes the sound, the feel of my voice. But otherwise he likes a sound close to his own.

"The danger of having an unusual voice is you can end up listening to yourself and becoming self-conscious and conceited about it," he continued. But there's no question about its appeal. He heard once that a man with a similar sound grew a beard and introduced himself at parties as James Earl Jones.

In " 'Master Harold' . . ." Jones plays Sam Semela, a waiter in the St. George's Park Tea Room in Port Elizabeth, South Africa. It is the most directly autobiographical of Athol Fugard's plays, and in fact is dedicated to Fugard's father, who is an offstage presence in the play, and to the real Sam, who was brother, father and friend to the young Harold/Athol. Their relationship endured despite the rupture dramatized in the play, a break caused as much by the pressures of apartheid as adolescent rudeness.

Jones has known Fugard, who is an actor as well as a playwright, since 1964, when he played one of the two brothers in the American premiere of "The Blood Knot." " 'Master Harold' . . ." is his fourth Fugard play. Fugard is a small, intense man whose own interior complexity and frequent torment make him and Jones an interesting combination. Jones' first impression:

"Knots. Oak. Gnarled knots or briar; he smokes briar pipes. I didn't know then that he had been a merchant seaman and was used to barroom brawls . . . When I worked with him in ' A Lesson From Aloes,' he would pick out the scuzziest bars. He was never afraid.

"All of his plays are about friends or relatives meeting or confronting each other in the space of one day and sorting out their problems. Their problems are always affected by apartheid, and they deal with each other in that context, but the plays are not about apartheid. They are very bare-bones characters. There are no layers of sophistication. The blacks and coloreds in his plays have no education, or very little. An actor finds himself confronted with essential humanity. There is no eloquence to escape into; the poetry is on a basic, gut level."

He has never been to South Africa. He passed up a chance to take his one-man show about Paul Robeson there several years ago after talking to a Pakistani woman who had recently been released from jail where she had been sentenced for anti-apartheid activities.

"She said, 'Yes, they would allow you to go there with a red carpet, and give you an integrated theater and carte blanche, because they know you'd be leaving. But there are 100 young black actors who could play that role who would not be allowed to.' "

He decided on that basis not to go, but not because he believes in boycotts. "Being from Mississippi I know a boycott is not always the most effective thing," he said. "Opening up a society by bringing in new ideas and new thoughts can be more helpful."

Jones did his second Fugard play, "Boesman and Lena," right after he had finished a long run with both the play and the movie of "The Great White Hope."

"I had gotten a taste of the heights of success and notoriety," he said, conveying the impression that the memory was not very pleasant. "I wanted to get my feet on the ground again." He found his feet in the bleak, existential terrain in which the nomadic Boesman and his wife, Lena, travel in despair. "For the first time, I never worried about what the critics would say," he said.

One climactic scene in " 'Master Harold' . . ." requires the actor playing Harold to spit in the face of his friend Sam. During rehearsals for the premiere of the play at the Yale Repertory Theater, Fugard, who was also directing, found the actors were avoiding this moment. "Finally, Fugard decided to take matters into his own hands," wrote Mel Gussow in a New Yorker profile. ". . . When it came time for the boy to spit, and he didn't, Fugard . . . placed his hands squarely on either side of actor Zakes Mokae's head, held it, and spat repeatedly in his face--a shower of spittle in the face of Mokae, who, Fugard says, 'is a man I love more than any other man I know.' "

Jones had no such hesitation when it came time for his rehearsals to replace Mokae on Broadway. "I had heard that story of how Athol broke the ice," he said, laughing. "And I didn't want Athol spitting in my face. So I said to the actor playing with me: 'Haul off and hit me with a good wad, because if you don't Athol will.' "

Shocking moments like that are bread and butter to Jones. "I love grotesquerie. I should have been in the theater of the insane . . . I don't like to do what makes people feel good. I'd rather be in a play that disturbs. You have to take those chances for exposing something raw about life."

Fatherhood may have come late to Jones, but he was more than ready for it, and gets almost mystical talking about it.

"I think for the last five years I was going around and every time I saw a pretty girl, I'd say, 'My name is Jim, can you have a baby?' "

He met Ceci Hart in 1979 when they were both in the television series "Paris." At the time she was married to Bruce Weitz, who has since earned plaudits for his role in "Hill Street Blues." Jones and Hart were married last year and Flynn arrived four months ago.

"I've always felt having children was a necessary part of the cycle of life. Not just to celebrate life, but to continue it . . . Knowing my father, I see something special in his genetic makeup, things that deserve to be passed on. And when Flynn came out looking like a combination of my father and hers--whom I love--I knew it was a miracle. I didn't think it, I knew it was a miracle."

His father, Robert Earl Jones, also an actor, played the part of Luther in "The Sting" and recently, at age 73, completed a film with Ralph Bellamy. Because his father left Mississippi before he was born, Jones did not really know him until adulthood, when he moved to New York. The son may have exceeded the father in fame and glory, but he clearly retains a deep affection for him.

His wife's father is a colonel in the Army, a profession that Jones considered after two years as an enlistee, before a thoughtful superior suggested he try acting first.

His disappointment with "Othello" was so strong that he considered doing commercials for the first time in order to make enough money to avoid another tour. Zoe Caldwell, who came in to replace director Coe in Baltimore, saved the show, he said. "It needed a woman's sensibilities," he said. "Peter Coe virtually destroyed the play. It was as if he hadn't read it. It was devoid of any aspect of love. It was two productions: the comedy of Iago and the almost-tragedy of Othello. For some reason when those two productions clashed there was a perversity about it that the New York critics loved . . ."

"It just needed a good mother to sort things out," Caldwell said. "Someone with a clear view to discipline the family. James is a truly great actor who was not yet playing Othello." And was he easy to direct? Her answer was unhesitating: "No. He's a very complex person."

As an actor, Jones is as game for villains as for heroes. "If I could pass, I'd like to play Goebbels, or Mussolini," he said. Actually, his last job was recording the New Testament on cassettes. It was not a religious mission, but a challenge that appealed to him.

One of the challenges of " 'Master Harold' . . ." was learning enough ballroom dancing to pass as a one-time prize winner. Before doing the play, he thought ballroom dancing was something for old people to do on New Year's Eve. Now he has come to appreciate its peculiar beauty, the sense of harmony that drew Sam Semela. In "real life" Athol Fugard did learn to dance from his Sam, and went on to win trophies of his own in ballroom competitions.

"I'd like to learn to dance well," Jones said. "I'd like to learn the waltz well, and take Ceci to Roseland."