The GA-20 was Gibson’s counterpart to the popular Fender Deluxe in the early 1950s. The preamp section on the GA-20 is comprised of a pair of 6SJ7 tubes while the power section uses a pair of the ever popular 6V6GT power tubes in a push/pull configuration. These amps have that smooth, natural breakup at relatively low volume that’s perfect for the house or studio. Go ahead and toss that overdrive pedal in the trash- you won’t even consider it after you hear the thick, luscious drive from this one.  A word about purchasing any of these rare Vintage amps, “these amps need to be regularly cared for”.   These are very old and may need to be or may have been serviced in the past. We recommend that any of these amps upon purchase be serviced and then regularly looked over by a skilled amp tech. Used amps are sold here on a strictly as is basis. Thanks!