Theater at Harvard is like the food at Durgin Park--it's reasonably priced and there's a lot of it, but it's not necessarily gourmet fare.

Still, you have a pretty fair chance of avoiding a dramatic case of indigestion if you're finicky about your theater-going.

For example, whether or not you're a Gilbert and Sullivan fanatic (and if you're not, you probably should be), you're likely to enjoy any production put on under the auspices of the Gilbert and Sullivan Players. The Players come closer than any other theatrical group at Harvard to being an ensemble company. Cast members perform together in show after show; some, like the versatile Tom Fuller, who played just about every G & S hero from Ralph Rackstraw to Nanki Poo before directing Iolanthe last fall, are Harvard legends.

Unfortunately, the Players' combination of expertise and an infallible repertoire is a rather poorly kept secret; this fall's Pirates of Penzance will no doubt sell out almost as soon as publicity posters go up, so if you're planning a trip to the Agassiz, plan early.

Your next best theatrical value is probably the Loeb Ex, mainly because it's free. You don't even have to trek all the way up to the Loeb the day before (as the ads suggest) to get tickets. Just get there half an hour before curtain, and stand in line. The Ex is so small that any seat is bound to be good.

"Ex," of course, stands for experimental, but it's not always clear what the adjective refers to. Sometimes--rather often, in fact--it means that the plays in question are rarely produced, either because they're as-yet undiscovered classics or because they're student authored. The four plays slated for October are, sure enough, plays I've never heard of. On the other hand, you'll not uncommonly encounter at the Ex such frequently revived works as The Crucible and The Glass Menagerie; in those cases, the only thing experimental about the productions may be their directors, who may be making their theatrical debuts.

While Ex productions naturally vary in quality, they're often surprisingly good. Mainstage productions, on the other hand, are often surprisingly bad, not to mention more costly. It's hard to say why this is. Over the years the Loeb has gained a reputation for both technical virtuosity and lacklaster performances. Sometimes the problem has lain with the plays themselves. The Harvard Dramatic Club has usually tried to shy away from scheduling already overproduced works. A commendable policy, this, but one which has resulted in the past in the production of such gems as More Stately Mansions, probably the worst play O'Neill ever wrote, and the travesty of The Tutor, a heavy-handed Brechtian non-masterpiece, whose German director cast members reportedly had trouble understanding. It showed.

You should give the Loeb a chance, however. Each year the Loeb ropes in at least one professional director, and not all of them are incomprehensible. A production two years ago of Sheridan's The Rivals was marvellously funny, its acting near-professional in caliber. And Black CAST, which generally gets one slot each year, can be depended on for an energetic production.

This fall's Loeb schedule looks promising: George Bernard Shaw's Candida coming up in late October, and Scapino, an adaptation of a play by Molier, and Oklahoma!, directed by Andy Cadiff, who has been trying for years to make the corny musical into an art form.

The other major musical productions this fall will be the Radcliffe's Grant-in-Aid's A Funny Thing Happened on the Way to the Forum in early November. Last year's Grant-in-Aid musicals, George M! and Godspell both received top-notch notices, so A Funny Thing... might be worth checking out. But if you want to see Zero Mostel, go into Boston instead--he'll be starring in a "new" version of Fiddler on the Roof, which is stopping here on its way to Broadway.

If you're anxious to get off the beaten path, you should be following the Harvard Premiere Society--that's its specialty. The Premiere Society was originally founded as a vehicle for the talented Philip LaZebnik '76, who was having trouble getting his new musical Mad About Mintz produced by Radcliffe Grant-in-Aid. Under the society's auspices, Mintz finally made it onto the Agassiz stage, and the rest is Harvard theater history. Last year the Premiere Society sponsored what turned out to be the hottest show in town: Do It Yourself, a collage of skits and songs written by Harvard students and Paul Cantor, who normally hosts a show of his own in Hum 118. Do It Yourself was a real bonanza; night after night, the Lowell House JCR veritably creaked with Harvard notables crushed together at well beyond the room's capacity.

This year the Premiere Society is trying to do it again with Summer Work, an original play by Mark O'Donnell, who has written the last three Hasty Pudding Shows. (A note The Pudding Show, performed for several weeks each spring in drag, is recommended only for the very rich--tickets are around $6.50--or very preppy, or both.) Summer Work, to be presented at Dunster House, is supposed to be O'Donnell's stab at serious writing, but it will probably be very funny anyway.

Last, but not always least, are House productions. These are a variable quantity; in general, the plays chosen by the Houses necessarily have a wider appeal than those at the Loeb, since each House production has to break even. While production values are uneven, the acting in the Houses is of as high a quality as you'll find elsewhere-in thz University. Another advantage is spontaneity--no need to buy tickets in advance, since there are no reserved seats. Once Upon a Mattress will be at Leverett this fall; look out also for Oscar Wilde's The Importance of Being Earnest at Kirkland.

The theater season--for spectators, at least--doesn't really begin here until mid-October. But the next few weeks are a banner time for would-be participants, with auditions going on everywhere at once. On the other hand, if strutting about the stage is not your raison d'etre, then you'll just have to nurse your appetite while you wait for the feast to begin.

Don't Bother Me, I Can't Cope. An award-winning black revue at the Charles Playhouse, 76 Warrenton St. in Boston, through October 31. Performances Tuesday through Friday at 8 p.m., Saturday at 6 and 9:30 p.m., and Sunday at 3 and 7:30 p.m.

Enter Laughing. Presented by the Cambridge Collective at the Boston Center for the Arts, 539 Tremont Street, Boston, through October 3. Performances Thursday through Sunday at 8 p.m., with Sunday matinee at 3 p.m.

Mollie Ockett. Music from more than ten Broadway shows and a Pequawket Indian named Mollie Ockett, at the Warrenton St. Playhouse, 71 Warrenton St. in Boston. Performances Tuesday through Thursday at 8:10 p.m., Friday and Saturday at 7:30 and 10 p.m. and Sunday at 7:30 p.m.

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