With their latest release, Waxing the Gospel: Mass Evangelism and the Phonograph, 1890-1900, the duo raises an already high bar by offering 102 selections and a nearly 400 page hardbound book that together explore an important, if sadly ignored, subject: the evangelism movement of the late nineteenth century, the religious songs and singing the movement produced, and how the songs became material for professionals and amateur musicians and singers during the dawn of phonograph recording.