Huun-Huur-Tu is a Russian folk music band, hailing from Tuva and known for their throat-singing.
Huun-Huur-Tu and Zappa
On 2 January 1993 Matt Groening approached Huun-Huur-Tu after a concert in Caltech, Pasedena, California and invited them to Zappa's house in 1993  , where they attended several Friday Night soirées. One of their performances was accompanied by Kongar-ool Ondar, who wasn't a member of their band, but also an accomplished throat-singer. Kongar-ool Ondar's performance with Huun-Huur-Tu, The Chieftains, L. Shankar and Johnny "Guitar" Watson on 8 January 1993 was filmed by a BBC camera crew making the documentary BBC Television Tribute (later rebroadcast in the U.S. as the A&E Biography). 
Zappa later produced Huun-Huur-Tu's album Dance Me This (2015), on which Kongar-ool Ondar performed again.
According to the booklet of Huun-Huur-Tu's Horses In My Herd their song Song of the Caravan Drivers was a favorite of Zappa, which is why they dedicated it to him.