Kind of? It would be a similar concept to setting your guitar's volume at around 6 or 7 (roughly) then setting your amp as if the guitar is at max volume, for home playing or your gig or whatever, then after that, turning the volume knob all the way up. You're going to be sending "more" signal to the amp. It's just easier, imho, to step on a pedal. Except it gives you the capability to put out even more output than a guitar set to 10. The usefulness really depends on what you want out of your gear. One of the coolest sounds I've ever heard...and I don't know what kind of guitar I grabbed, was with a DOD preamp/boost into a Peavey Vyper VIP something or other. It was just the grossest narliest fuzz sound I've ever heard, but still very musical. There's basically no guitar that can push the front end of that amp to saturate at that level without a clean boost.