Oh Happy Day (Koplow) by Lawrence Welk and his Champagne Music, vocal by Larry Hooper (CD audio source) The deep-voiced Hooper is well-remembered ...
To the user who requested it, here's Larry Hooper to sing "Oh Happy Day"
From the premire show: Here`s Larry Hooper! (1955)
Originally from 1964 (the last season of The Lawrence Welk Show in black-and-white), this clip was recorded from Iowa Public Television on June 16, 2012.