Is the sweet spot for your Monza just a little to loud for you? This is our Low Output Standard Retube Kit for the Dr. Z Monza Heads and Combo Amps. It contains a matched pair of JJ EL844's for power to drop the overall output a couple decibels, a JJ GZ34 rectifier tube along with two JJ ECC83S's with one being current balanced for the phase inverter in V2.