Welcome to this week’s Release Round-Up! Various Artists, Get on Board the Soul Train: The Sound of Philadelphia Vol. 1 (Snapper/United Souls)  (Amazon U.S. / Amazon U.K. / Amazon Canada / Burning Shed) Get On Board the Soul Train: The Sound of Philadelphia International Records Vol. 1 is the first in a series of box sets from the U.K.-based United Souls label, an imprint of Snapper Music, which will ultimately collect the entire Philadelphia International albums discography on CD.  The slipcased, 8-CD/1-12″ single hardcover book-style set will feature the following eight albums, originally released between 1971 and 1973: Billy…