I seem to recall a conversation with someone on the internet that claimed to be involved with Zappa in the studio, that Zappa had a quad setup up to Joe's Garage. There have also been rumors that many other Zappa albums did get quad mixes that never got released. How much of this stuff is true, and how much of this still exists in the vaults, and how good these quad mixes would be are all mysteries, though. But, there certainly is a possibility some sort of quad mix of Joe's Garage was done, and is sitting in the vaults, rotting away, where it will sit for all eternity, as the used prices skyrocket for the now out of print Zappa catalog, since it seems no one is capable of at least keeping the damn catalog in print, let alone release unissued stuff.
