Want maximum gain to go with the aggressive E34L sound? This is our High Gain Option Retube Kit for the Ampeg VL-501 and it contains five Handpicked High gain ECC83S's one being current balanced for the phase inverter in V5. The default power tubes are a matched pair of the JJ Electronic E34L’s but you can configure this kit to use the JJ EL34II's, EL34’s, KT77’s, Big Bottle 6CA7’s or 6550's by clicking on the "Customize" button.