Most of Houston knows Ronnie Renfrow from the Ronnie Renfrow Big Band. But bandleader Renfrow turned radio host a while back and has been spinning jazz and big-band tunes on the Swinging 650 -- Classic Cool show on 650 AM for more than a year now. He's on air seven days a week with partner Tom Richards (weekdays from 5:30 p.m. to 8:30 p.m. and weekends from 1 p.m. to 8:30 p.m.). This is swinging music, bound not by era or genre but by quality, and he plays everything from Frank Sinatra to Norah Jones. Renfrow knows all about each song and singer, the backstories, the gossip and the official line. Funny, smart and on the inside, the show is the coolest spot on the AM dial. And they take requests; listeners can call in to 713-965-0650.