Want all the gain you can get? This is our High Gain Option Retube Kit for the Dr. Z Mini Z Heads and Combo Amps. It uses a single handpicked High Gain ECC83S for the front end and the default power tube is a single JJ EL84. With the Customize option you can configure this kit to use a JJ EL844 which will drop the power output a couple decibels (ideal for players wanting decreased headroom/output).