How about that Barbershop music?  It's an interesting sound.
I agree, the harmonization is so nice to hear, don't you think? 
Indeed.  I wonder what the largest Barbershop music group is.
I'm not sure, but there is a Barbershop Harmony Society that promotes the art.
Oh cool.  Do you know when the Barbershop Harmony Society started?
It was founded in 1938 in Tulsa Oklahoma. 
Do you know how many members the Barbershop Harmony Society currently has?
As of 2014, there are 23,000 men in the United States and Canada a part of the Barbershop Harmony Society