I have almost no understanding of the electronics involved in tube amps, so do not take my word for anything. But..... For mismatching with 5 jack amps like the JVMs and new DSL40CR & 100HR, I have seen it explained like this: The OT needs to 'see' 1 correct load of 16 (1x16), 8 (2x16), or 4 (2x8) ohms. Plugging a 16 Ohm speaker into one of the 8 Ohm jacks shows the OT 1/2 of a correct load. Plugging an 8 Ohm speaker into one of the 4 Ohm jacks shows the OT 1/2 of a correct load. 2 x 1/2 of a correct load = 1 correct load. Can someone explain why this might be bullsh#t, if it is bullsh#t. BTW I have NOT tried this out. But have heard of people posting in this forum using it with success. No one has posted saying this blew up their amp (that I have seen anyway).