We’ve written about the history of the Gibson GA-5 before. Basically, the GA-5 was Gibson’s first practice amp offering. Not only was the circuit nearly identical to the Fender Champ, but the GA-5’s cabinet was suspiciously similar as well. Eventually, Gibson adopted a more original exterior design, but the circuit remained pretty much the same. This means that a GA-5 of any vintage is an extremely affordable equivalent to a 5F1 Champ.