You know the song before you remember you know it -- 'On the Wings of Love,' every wedding and every slow dance for forty years -- and the man who wrote and sang it is standing on a vineyard terrace in Temecula in early September. Jeffrey Osborne fronted L.T.D. before the solo career, and at this point his voice is a piece of American muscle memory; he could phone it in and still level the room, except he never does. Saxophonist Marqueal Jordan opens the night. Thornton runs its usual ritual around it -- estate sparkling wine, dinner service on the terrace, the hills turning violet as the set builds. This is the season winding into its warm, golden stretch. Bring your parents, bring a date, bring the friend who needs one perfect Saturday. Some voices you should hear in person while you still can.