I have recently started gigging with my band. I have a Marshall MG250dfx which i use an EQ and Disortion pedal with. The amp is OK for venues where they have a PA System but when it comes to venues that do not have a PA System i have to crank the amp to full volume. When my amp is cranked its stil not as loud as the drums and clarity goes out the window. I'm looking to upgrade to a valve amp but am unsure of what to get. I don't have too much to spend on an amp, about £500. I play fast heavy stuff, similar to Cannibal Corpse and Slayer. What amp would you suggest? Thanks