[quote name='colinmk' post='307452' date='Oct 15 2008, 10:48 PM']Hi guys,
I have (hopefully) just aquired an SVP-Pro blackface too. From what I'm hearing above it seems like a good idea to think about upgrading the valves. I will have a listen to it first when it arrives and if all seem fine then I may just stick with the stock but I'm always trying to find the best tone possible.
Anyway if I do decide to upgrade then the above mentioned from Watford valves sounds good but I will be wanting a real driving gritty tone if possible from it when I need it. Will this be achievable with most 12au7s like the Phillips? Or should I look for something that has been known for this type of sound?
Cheers.[/quote]
is the 12au7 the 'drive' valve ?
interesting...