Stephen F. Temmer, 64, a retired recording and broadcasting equipment exec and noted audio technician, died Oct. 8 in N.Y. of complications from AIDS.Temmer was founder and president of Gotham Recording, Gotham Audio and other companies. A native of Vienna, he sang in the Vienna Boys Choir before his family fled the Nazis in 1939. While a studio engineer for ABC in the 1940s, he broadcast the first taped radio programming from N.Y. and made the first recordings of the Metropolitan Opera for broadcast. He was acoustics consultant on the renovation of Avery Fisher Hall and a technical adviser to the Watergate prosecutors on the famous gap on a White House tape. A brother survives.