MY Leo loved music, understood it. He was somewhat of a loner; his friends were Tchaikovsky, Beethoven, Bach, and Debussy. He was born during the Great Depression, and the only instrument he ever owned was his voice. It was a beautiful, haunting, lyric tenor; he could harmonize, solo, or just plain break your heart. Plus he had an incredible smile. He worked for a notions store on Eighth Avenue in Manhattan, and on paydays he'd bring over records for me to play on the hi-fi. ''You hear that note?'' he'd ask. ''Wrong notes bug me.'' ''You're a perfectionist,'' I told him. ''Only in music,'' he winked. I was hooked, and so we were married, moved to the suburbs, had children, a big mortgage, and rough times. The children made friends with an old couple who lived in a shack across the road. They let the children pick apples from their tree, and eventually sold us their old upright piano for $50. For years we could smell the kerosene the couple used for cooking whenever anyone played the piano. I insisted the children get piano lessons. Leo accepted the added burden graciously. Mark, our 10-year-old, would not practice unless I stopped whatever chore I had to do and sat with him. He was studying ''Moonlight Sonata,'' one of Leo's favorites. I sat beside him on the bench and watched him practice. In the process, I inadvertently learned to read notes. As Leo's birthday approached - and the money for Pendleton shirts, 35-mm cameras, or turtleneck sweaters did not materialize - an idea began to shape in my thought. I'd learn to play the ''Moonlight Sonata'' for him. We had a record of Madame Stefanski playing the piece (''like a woman in love,'' Leo said). I was smug enough to think I could learn to play it as well as she did. So I began to practice. I was obsessed with practice: morning, afternoon, anytime Leo was not home. I wanted so much to bring this man pleasure, this husband of mine whose most frequent question was, ''Will it make you happy?'' I stopped dusting almost entirely and let the kids take their own meals. If they noted my overzealous conduct they were too polite to mention it. As for me, I couldn't wait to get up in the morning so I could practice. Finally, it was the evening of Leo's birthday. I baked a cake, set birthday candles on it, and waited for dinner to end. Because he had perfect pitch, I never let the children practice in the evenings. I couldn't do that to him after a hard day's work. Now I was afraid what he'd think of my playing. I waited until we had all sung ''Happy Birthday.'' ''I'd like to play something for you,'' I said. ''Spare me,'' he smiled. I walked into the living room, turned off the radio, sat at the piano, and blew him a kiss. ''To Leo with love,'' I announced. His eyes were eloquent. ''What is she doing?'' they asked. For weeks I'd fantasized about playing before vast, enraptured audiences. It made things easier. I began to play. When I finished, there was a moment of silence. Then ''Bravo!'' he cried. ''That was wonderful, a God-given gift,'' he added, kissing me. ''That,'' I said humbly, ''is your birthday present.'' His eyes glistened, ''I'll never get a better one.'' The years that followed brought Pendletons, turtlenecks, and even a 35-mm camera. But they only got a polite ''Thank you'' and a ''When are you going to play for me again?'' But I never did. Even though I had enjoyed the playing, the practice, the rapture, I stopped practicing after his birthday. I didn't go on to realize a late-blooming talent; all I wanted was to give him something special. The God-given gift as it turned out, was that moment. It was enough.