The Army Band sent out a release the other day telling us that Specialist-6th class Neal Corwell will play a solo euphonium concert tonight at the band's Brucker Hall, so it seemed the right time to go out to Fort Myer and find out something about Specialist Corwell and about his instrument.

In all its massive 20 volumes, the New Grove Dictionary of Music and Musicians relegates the euphonium to two pedantic and not very illuminating paragraphs. But that was all right, because Neal Corwell knows a great deal more about the euphonium than Grove could ever imagine.

He said he thought his visitor might know more about classical music than about military band music, and said, "You probably think that it's used just in band music, but that's not quite true. There are some exceptions." And as the conversation proceeded he kept ticking off familiar music where solo passages are scored for euphonium, but where you may have thought you were hearing instead a trombone or a tuba--in the great comic bass solos of Strauss' "Don Quixote" with which Sancho Panza turns tail after the Knight's pratfalls; in the Polish ox cart section of "Pictures From an Exhibition"; the Mahler 7th, and Holst's "The Planets."

"There's one catch," he noted. "Some orchestras don't have a euphonium, so they have to give these parts to the trombone or the regular tuba," which the euphonium resembles in shape. But put on a recording of the Strauss, for instance, and it is clear that this wonderful moment is exactly right for the euphonium. The trombone isn't fat and lumbering enough, and the tuba is too clumsy to play it fast.

Corwell hasn't played in a full symphony orchestra yet, but he knows most of the parts he mentioned off the top of his head. Corwell, who is only 22, joined the Army Band last summer. He had been discovered through auditions about a year ago to be a budding young virtuoso of the formidable instrument. Corwell grew up on a farm in western Maryland, switched from the trumpet to the euphonium in the seventh grade because Clear Spring High School needed one and then proceeded to spend his years at Frostburg State College mastering the euphonium to such a degree that most of the other music majors must have been shoved into the shade.

The first tuba player of the Pittsburgh Symphony came weekly to give him lessons. And during Corwell's four years in college he gave six separate recitals there, each with a different program, and apparently he turned Frostburg State into one of the real hotbeds of the euphonium in the music world.

Last week Corwell was back at Frostburg State trying out the program that will introduce him to Washington audiences tonight. A highlight is the premiere of a new work, "Four Short Narratives," that Corwell has written; there are four sections--"Morning, Day of Celebration, Dusk and Night." "It's between seven and eight minutes long and they are just little ideas that I wrote and then I continued them by turning them around a little."

Corwell is one of seven euphonium players in the Army Band, but the band is such a multifaceted organization that the seven never find themselves playing in the same place at the same time. They do every job from bugle calls at Fort Myer to playing as the Strolling Strings at White House state dinners; it adds up to more than 3,000 jobs a year. For all these duties, the band has close to 150 musicians to draw from. The marching band always has two euphonium players.

Time and again the band has provided the springboard for distinguished musical careers; the two best known are Eddie Fisher and Steve Lawrence. Also, there are opera stars Richard Stilwell, John Cheek and George Shirley and instrumentalists in orchestras all over the country.

Corwell admits to still being a bit stunned at all these possibilities. "It was way into college before it occurred to me that I could do anything but teach with the euphonium."

Now he's much more career-oriented. He's now a student of Brian Bowman, a distinguished euphonium player. "He's not really very famous," cautioned Corwell, "but he's the only person ever to play a euphonium concert at Carnegie Hall."