A cabinet usually has four 12" speakers when it comes to guitar. Although some have 10" speakers and some, like Dimebag Darrel's signature amp, have two 15" speakers. When you have one cabinet it's called a half stack. With that in mind I'm sure you can figure out what a full stack would be. Tube amps are driven with tubes opposed to electrical like solid state are. The difference is all in the tone. Some people prefer the tone of a tube amp, and some say that tube sound travels over a band much better than a solid state.

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