Robert Noehren is that rarity, a 79-year-old maverick.

For many years head of the organ department at the University of Michigan, he believes that much of the profession is in thrall to the academy. And, in an age when more and more of his colleagues are deserting electric action for mechanical action - i.e., tracker organs - he finds himself increasingly drawn to the former.This weekend, moreover, he makes his debut on one of the most celebrated electric-action organs in the world, the great organ of the Mormon Tabernacle, on which he will perform Saturday, Oct. 27, at 7:30 p.m. Admission is free.

"I heard it both before and after it was redone," he says of the Tabernacle organ's recent renovation, "and it's a much better instrument than it was when it was left by Aeolian-Skinner."

To show off those improvements, he has put together a program spanning the music of Cabezon, Buxtehude and Bach (including the Toccata and Fugue in D minor) as well as that of Brahms, Franck, Reger and Messiaen, with his own Sonata thrown in for good measure. Reminding us that Noehren is a rarity in another way, an organist who has achieved distinction as a composer, performer and organ builder, with around 20 instruments to his credit.

"I was 50 years old and a full professor at Michigan," he says of that phase of his career, "and I got so frustrated with the organs I had to play that I thought I'd try to do it myself."

The instruments Noehren is proud-est of are those of St. John's Cathedral in Milwaukee, First Presbyterian Church in Buffalo and First Unitarian Church in San Francisco, on which he recently recorded a Buxtehude CD, one of more than 40 recordings, some of them going back to the early LP era.

But he doesn't always like the kind of playing he hears these days. As he puts it, "There are a lot of talented organists on the scene, with fine technique. But they don't get into the music the way pianists do. A couple of years ago I was here visiting my brother, who's a doctor, and went with him to the Bachauer Competition. The best of those young people are way ahead of us when it comes to putting the music across to an audience."

Part of the problem, Noehren believes, is that few organists exist outside the church or school, "with the school becoming more and more pervasive. And I think scholarship tends to inhibit the organist. Many of my friends and colleagues are more worried about whether they'll play a trill correctly than about whether it sounds convincing."

The movement to tracker organs he also sees as an outgrowth of the scholarly influence. "And it's such a clumsy instrument - I mean the large tracker organs, which you need to play the literature. When I was younger, the idea appealed to me, too. Then, after the war, I went to Europe and began playing those old instruments and realized it wasn't for me. It changed my whole point of view. But these days, in order to be respected in this profession, you've got to be on that bandwagon. Again, it's such an inhibiting affair."

Just the same, Noehren is respected in the profession, enough so that in 1978, following a recital at Alice Tully Hall, he received the New York City Chapter of the American

Guild of Organists' first International Performer of the Year Award.

Similarly his recordings of the Bach Trio Sonatas earned him a Grand Prix du Disque, and his 1957 Urania recordings of the Bach-Vivaldi concertos were recently reissued on CD.

"I hesitated to put my own Sonata in there," he says of Saturday's program. "But I think it's an interesting piece, a product of the time I spent studying with Hindemith." Was that at Yale? "No, he came to Buffalo before he went to Yale, so we sort of had him to ourselves for a few months.

"That's when I was organist at St. John's Episcopal Church in Buffalo," Noehren recalls of that distant time. "I enjoyed it and sometimes I miss it. But I don't miss the weekends off."