He makes his sounds with a bunch of different hardware electronics.
These two posted below are favorites.
One of these songs are from his album "Hermaphordite" and the other "Alien In A Garbage Dump"
Eric Copeland - Spacehead
Eric Copeland - Reptilian Space Beings Shapeshifting Bloodsucking Vampires
Phoreladeliah did a great interview of Eric Copeland you should read it
(Avey Tare + Eric Copeland)