Thanks guys, yes I know I should take this to a tech etc but I barely have time to look at Basschat these days let alone find a local guy (most have disappeared round here), drive it there, collect it etc, so frankly thought I'd let someone else have that pleasure. I've checked the tubes I've used with it and both models are pretty low gain so I might try a higher gain version which might do the trick, in which case the price goes back up again