The tag line "The Voice Of Rock" has been used for quite a few singers, but one could argue that Glenn Hughes wears the title most effortlessly, having left his first band (Trapeze) to take over bass and share lead vocal duties in Deep Purple, and then later Black Sabbath.
Along the way, Hughes has released 28 albums as a solo artist and another 17 records with various bands, most recently as part of Black Country Communion (four albums between 2010 and 2012) and 2014's excellent California Breed.
And in 2000, Glenn released A Soulful Christmas, and I am sure you can guess by the title what kind of record this was.
Surprising to think of this guy as a former lead singer for Black Sabbath, right?
Finding this one on CD may be difficult, but it is available as a digital download (a used copy is listed on Amazon for $167.40 versus $8.99 digital).