I have heard the past, and it works.

An old 78-rpm recording of Les Paul and Mary Ford sounded better than standard stereo when it was played through the phonograph pickup that Edward F. McClain invented four decades ago, the five-foot-plus-high stack of amplifiers, tuners and switching devices that he has been assembling and modifying since the 1940s, and the 1930s-vintage speakers that he scrounged from movie theaters.

And a quadraphonic recording featuring Janis Ian sounded incredibly clear, resonant and beautifully spaced to a visitor sitting in what McClain calls "the sweet spot"--the right hand side of the couch in the small living room of his home near Andrews Air Force Base in Prince George's County.

Quadraphonic sound complements the front right and front left speakers of stereophonic sound with two speakers behind the listener that reproduce the sound reverberation.

McClain says sound reproduction has interested him as far back as he can remember, and two of the five patents he holds are in this field. Asked if he made money from his patents, McClain responded: "No. Never a nickel." He mentions this to support his contention that "patents for an individual are a very, very long shot."

He believes that very few people make any money on their patents unless they develop them as employes of companies with a policy of handing out bonuses to successful inventors.

McClain remembers being interested in sound and records as early as age 2, when he had pneumonia and asked that the family phonograph be taken to his room and records played for him. "When I was a kid about 15 years old, I built my first phonograph," he said.

McClain came to the Naval Research Laboratory in early 1942 after studying electrical engineering at the Missouri School of Mines. While at NRL, he received a bachelors degree in electrical engineering from George Washington University. He worked at NRL on submarine radar and aircraft navigation systems until the early 1950s, when he switched to the radio astronomy group. He was head of that group when he retired in 1968 because of medical problems that today prevent him from spending large amounts of time and energy on inventing.

He hold patents on a low-mass, high-compliance phonograph pickup and a variable-radius, truncated stylus for both 78s and the slower transcription records used by studios in the days before long-playing, high-fidelity records were invented. He also holds three radar-related patents.

McClain bemoans the failure of quadraphonic sound to catch on the way hi-fi and stereo did, citing the existence of three competing but incompatible quad sound systems, the delay in perfecting the necessary sound decoders, and government inaction on proposals for quadraphonic broadcasts over FM radio as some of the reasons that quad flopped.

How much time does McClain spend each day listening to his one-of-a-kind system? "Very little," he answered with a grin.