The fills.

That's why Charlie Baty started really playing the guitar. In the early 1970s, when he met singer, songwriter, and harmonica player Rick Estrin, "I had never played guitar in a band," Baty said in a recent phone interview.

At that time, Charlie was the singer and harmonica player in his own band, Little Charlie & the Nightcats. But with Rick already an accomplished harmonica player and set to join the band, Charlie picked up his guitar and studied his Chicago blues heroes.

Turntable purists have a friend in Coldplay, as next week the band releases an import-only box set of singles on vinyl but not CD. Entitled simply The Singles 1999-2006, the 15 seven-inch records in the Parlophone project feature plenty of live B sides and the hard-to-find Blue Room EP split into two singles.

Rock and roll, in its conventional hard-rock form, seems to have all but disappeared. Who practices this archaic type of musical expression, with its earnest guitar-bass-drums-vocals format and no acknowledgment of irony or speed metal, alt country, world music, hip hop, emo, or any other musical fashion of the past 20 years except grunge? Pearl Jam seems the last vestige of this noble tradition with both credibility and market presence.

Trend-chasing is less prevalent at the local level, of course, and Kewanee's Drunk Dead Gorgeous - playing at Penguin's Comedy Club on March 16 - creates unapologetic guitar rock that's heartfelt and played with passion. With its emphasis on acoustic guitars, the band's new-ish album, The Great Disillusion, sounds a lot like a collection of power ballads.

Bringing back memories of the warm scent from an Easy Bake Oven, Cake is prepping a new CD that features "scratch and sniff" fun in the disc's limited edition. Releasing B-Sides & Rarities on their own at (http://www.cakemusic.com) and bypassing a record-label deal, the CD features two crazy covers: Kenny Rogers' and the First Edition's "Ruby, Don't Take Your Love to Town" and Barry White's "Never, Never Gonna Give You Up." One more cover is featured on the limited edition's bonus disc: a live stab at Black Sabbath's "War Pigs" with guest Steven Drozd of the Flaming Lips. Budding video directors are encouraged to submit an original visual accompaniment to the "War Pigs" cover, with the band ponying up a $1,000 prize.