I have an SWR750x and it is a POS. I have had it 8months and it has been in the shop twice as the input jack keeps shorting out. This causes the effects to turn on and then they short out. I think the problem is a shoddy design. I asked the helpful gents at Fender for help and they have yet to respond. Great Customer service!!!!! When the thing works, it kicks ass but it cannot be depended on. Once it gets back from the factory authorized sevice center I am dumping it like a boat anchor and getting a real amp that works (prob Mesa Boogie Bass 400).