You can't change CDs when your hands are coated with drywall goo. Plus, who wants to climb down a ladder to pick out new tunes when you're in the middle of painting a ceiling? Better to just turn on the radio and let the random sounds wash over you. Not just any radio. The last thing a person who's knee-deep in an aggravating project needs is to hear some corporate robot spitting out the same twelve songs over and over and over again. What we design-on-a-dimers need is eclecticism, and that's what KCUR 89.3 gives us on Saturday afternoons. From noon until 4 p.m., the station fills the air with its two best shows: Cyprus Avenue and Sonic Spectrum. Cyprus Avenue is an institution in Kansas City, turning 25 this month. Host Bill Shapiro arranges his shows around single artists and genres, dusting off classic albums and offering fascinating tidbits of info about the artists between songs. Sonic Spectrum host Robert Moore spins a tapestry of tunes spanning all genres and generations. One minute you'll be listening to some old honky-tonk song, the next you'll hear Ween cooing about the joys of Zoloft. Before you know it, you'll be washing off your paint brushes, eager to pick up another project next weekend.