Gilding streetwise funk and soul with cascading orchestration and gleaming studio polish, Philly soul had become a consummate class act by the turn of the ’70s.The sophisticated local sound grew out of a close family of producers, songwriters, and artists—including the powerhouse duo of Gamble and Huff—housed mostly at Philadelphia International Records and Sigma Sound Studios (which later hosted a reverent David Bowie). Such signature artists as Teddy Pendergrass, The Delfonics, The Stylistics and Patti LaBelle ramped up the romance while the music itself expanded in scope and laid down the endless grooves that led directly to disco.