whats up guys and gals? i just got my amp back from repair , turns out it was the ic chip . first off i have a '96 or '97 marshall valvestate vs230. it has never been touched except for the service that was just performed . i had the ic chip replaced with a nte electronics ic chip. nte778a. ( is this an ok chip or ? other suggestions?) i want to replace the preamp valve . i have been told i should replace it with a 12ax7. groove tubes has different varieties of that model # and i have heard others recogmend jj tesla ecc83s. my repair man said the valve was fine , but if i can get a nicer tone from my amp just by replaceing something simple im on board . so whats up guys what do you think?