There were two drummers. One of the drums (jembe) was made of goatskin while the other set of three drums was made from the skin of a cow. You can see a jembe drum here:
http://www.tenthousandvillages.com/carved-djembe-drum
And here is a picture from earthrek.com:
My favorite link thus far discovered is:
The kora is an harp-like instrument used by storytellers. One of the performers played and sang with it. I did not understand the language, but the sound was very soothing. You will find samples of kora music at the site above. I hope you explore the wealth of art and music it contains. Yes, yes. Or as our guests would say, "Wow, wow."