Hello all! This is my first post on this forum!. I just got a Ampeg GVT52-112 today and it showed up with a weird sound on certain notes that ended up being a microphonic power tube. Now I have to replace them and I am not sure what kind to get. it is a 25/50w amp. I do not need it to be that loud honestly so I was wondering if I could get a pair of 6v6s and lower the wattage a bit or if that would hurt the amp, thanks!