gibson produced epiphone amplifiers in the 1960s. these were basically copies or variations of gibson and fender amplifiers. they used a tube design, and some had reverb and tremolo. gibson decided to launch a new line of epiphone amplifiers in 2005 with many different models, including the "so cal," "blues custom," and the "epiphone valve junior". the valve hot rod and valve senior were released in 2009. the valve hot rod is a 5 watt amp like the valve junior, but has a gain and reverb control. the valve senior offers 20 watts of power, with a full equalizer, gain, volume, reverb, and presence control.