By GUY FLETCHER

Staff Writer

Lamenting over the less-than-sparkling condition of his horns, Barry Tuckwell, perhaps the world's most famous French horn player, had a confession.

"I've had a bad Brasso day," he said, prompting laughter from the audience at the Maryland Theatre.

Officially, it was "Maestro Tuckwell Presents the Mysteries of the French Horn," but it could have been simply called Horn 101. For nearly an hour Friday afternoon, Tuckwell took his "students," more than 100 people who came for the free lunchtime program, through hundreds of years of horns and horn playing.

He amused and amazed the audience with his ability to play everything from a wooden Australian Aborigine horn to a 22-foot horn made of leather. He even played a horn fashioned from a garden hose with a funnel attached.

Tuckwell also played loud, off-tune selections once used by hunters in the French countryside.

"If they didn't get their prey with their bows and arrows, the noise would have killed the animals," he joked.

But there was a message to the humor - that the brass horn is a beautiful but sometimes-exacting instrument that can sound either wonderful or awful.

"If you sing, you can swoop in on a note, but with a brass instrument, if you missed it, you missed it," he said.

Truth be told, the French horn is not a perfect instrument, Tuckwell said.

"It doesn't work terribly well. It's sort of a stuffy instrument to play," he said.

You could make a French horn better and easier to play, Tuckwell said, but then it would be known as a trombone.

As for his own enjoyment of music, Tuckwell admitted it's difficult for him to be a casual listener when he really wants to pick apart each piece and each note.

"I tend to get involved. I rarely listen to something in a subliminal fashion," he said.

After the program, some audience members thanked Tuckwell, who will give his last solo performances with the Maryland Symphony Orchestra today and Sunday. He will retire as the orchestra's conductor in 1998.

"It's been a wonderful experience for me to build this symphony from nothing," he said.