Currently Being ModeratedJul 27, 2009 4:30 PM (in response to silentducks)Re: Line 6 Spider 3 full stack?
You would need to have a service center internally modify each cabinet for an 8 or 16 ohm load (depending on the type of cabinet you are using). You would then connect each output of the head to a 16 or 8 ohm connection. See the following link for more info:
Cabinet Connection and Ohm F.A.Q.