The Vox AC30C2X amp makes use of 3 x 12AX7 preamp tubes and 4 x EL84 tubes to deliver 30 watts of power. The AC30C2X tube amp uses 2 - 12" Celestion Alnico Blues, and includes a switchable 8/16 ohm output jack for powering an external speaker cabinet when you need to speak with a little more authority; using this jack will mute the internal speakers. Additionally, a second extension speaker jack allows you to run an extra 16-ohm cabinet along with the internal speakers for a fuller sound.