Okay I need a new preamp tube for my Marshall Vs100, the type needs to be a 12ax7. This amp sounds great for rock but when I wack up the gain for metal it only manages to get there with the help of my booster pedal. It's only a preamp tube with SS, but seeing as I have to change it is it worth changing the tube to make it sound better or just replacing it.

Thanks in advance
put a JJ ecc83 in it and be done.

But you still might find the amp isn't doing exactly what you want it to.
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