Question: where was it's always sunny in philadelphia filmed

title: It's Always Sunny in Philadelphia
text: The theme song is a piece of production music called `` Temptation Sensation '' by German composer Heinz Kiessling . Additionally , Kiessling 's work ( `` On Your Bike '' and `` Blue Blood '' ) can also be heard during various scene transitions throughout the show , along with other composers and pieces such as Werner Tautz ( `` Off Broadway '' ) , Joe Brook ( `` Moonbeam Kiss '' ) and Karl Grell ( `` Honey Bunch '' ) . Many of the tracks heard in the series have been taken from Cafe Romantique , an album of easy listening production music collected by Extreme Music , the production music library unit of Sony / ATV Music Publishing . Independent record label Fervor Records has also contributed music to the show . Songs from The Jack Gray Orchestra 's album , Easy Listening Symph - O - Nette ( `` Take A Letter Miss Jones '' , `` Golly Gee Whiz '' , and `` Not a Care in the World '' ) and the John Costello III release Giants of Jazz ( `` Birdcage '' , `` Cotton Club '' and `` Quintessential '' ) are heard in several episodes . The soundtrack , featuring most of the music heard on the show , was released in 2010 .