Zappa had originally intended this album to be released as a four LP set back in 1977 but Warner Brothers decided not to release it for various reasons I won't get into here.  Instead, they got Zappa to divide the original Lather album into four separate albums, often with different arrangements and mixes:  Zappa in New York, Studio Tan, Orchestral Favorites and Sleep Dirt, and a few songs found their way onto Sheik Yerbouti too.  Warner Bros. also decided not to pay Frank for his work.  So Zappa played the entire Lather album over the radio airwaves from which countless bootlegs have been made.  Ha ha Warner, you greedheads.  So finally, years later we get an official release of Lather, Zappa's magnum opus and arguably his best album and it was worth the wait.