I took my 1976 Marshall Mark II Master Model Lead 100 Head and 1960A cabinet to Dennis for a “tune-up”. When he finished it. He asked me to come over with a guitar and whatever pedals I wanted to use. He wanted me to try it out… “to road test it” I have never been asked to test my amp in the repair shop. We cranked it up LOUD! It brought back memories of when I first bought the amp. Even then, it never sounded this good! The man is a genius! He really knows how to make a Marshall “sing”. If you have a tube powered amplifier, and want to get the most out of it, bring it to Audio 3000 in Jacksonville, FL.