Just a couple questions I need answered. What is a tube amp? And what are advantages of it? Also, I play fast legato and metal...What kind of strings do I need for the best tone and proformance?

Thanks in Advance

A tube amp is an amp that works using valves instead of transistors. Tube amps are better sounding than transistors amps (most of the time). The kind of strings you use can only be decided by you which means that you will have to try out lots of different kinds to find the ones you like most.
For the string guage question...

Some say the buy bigger strings for a bigger sound, honestly though, that statement is only true for clean, medium crunch or OD, and the heavier channels on lower end amps. Higher end amps can take thin strings to a full on thick toned assault.

10's are usually the string of choice. 11's give you slightly more bottom end, not much, 9's are slightly thinner but they play fast.
Major of 7 String Legion 7 > 6

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