After paying off my Fender, I plan on buying a tube amp. My question is, what is the ideal surface to set an amp on so it performs to its best? Would it still sound the same on carpet compared to concrete/wood?
your amp should be fine anywhere... On carpet, you'll notice a bit more low end, on hardwood, more high end....

Back against a wall or in a corner, more low end, in the middle of a room, more high end... etc.

It's funny, I just got done explaining this exact thing in another thread hehe...
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