I don't know that amp but having a master volume on the amp is a neat feature. You put everything at max, including volume, then at the end of the signal the master volume makes the tone neighborhood friendly. I read somewhere that you lose some dynamics on some master volume amps though.
There are master volume pedals/attenuator out there also that I heard work great for attenuating and staying truer to your original "fully loaded" sound at lower volumes.