I'm still trying to figure what would be the advantage of doing that with a 12" wouldn't they be real bass shy.A 604 can be bass shy if not in a pretty big enclosure.If they were used with a sub could be good I suppose.I think most Altec speakers using the 12" (414) use 2 with a small format HF driver.Just for that reason that they don't produce enough bass.Is this wrong ??? I just don't see the advantage of doing that with a 12" my thought would be to just use a real 604.I dunno