Goodbye, classic rock. Hello, Bob.

WRRK-FM (96.9) has flipped to Bob FM, a varied format aimed at a wider audience that includes its former classic-rock listeners. The station made the switch at midnight yesterday.

The hybrid music format, better known as Jack in most markets, is a mixed stew of a playlist, stretching from the '60s to current hits.

Programmers see it as a way to engage radio audiences who've grown tired of formulaic, corporate formats that are heavy on commercials and light on variety. The target audience is 25- to 54-year olds, and listeners are about a 50-50 balance of male and female.

Second time in very recent memory that a major Pittsburgh commercial radio station "flipped" its format. Last time, it worked nicely for a couple of weeks -- no DJs, any music, cooperative work with the listeners to design the playlists around who listens when.

By now, it is filled again with annoying DJs who are not quite good enough to be demagogues but have the ego and ambition to keep trying out.

It must be sad to work in a dying media without much chance of reprieve. With newspapers -- another dying media -- the basic principle (content creation, editing, presentation) will last. Small radio stations, college radio stations, will also last for similar reasons. But as the competition and the market scales up to everyone (internet broadcast), the ClearChannel and Infinity Broadcasting model (cookie cutter format) won't work. And the losers will not necessarily be CC or IB (their formats work, apparently), but definately the smaller market DJs.