I'd recommend using a High Pass Filter. Lower and inaudible frequencies gobble up the amps power and make the drivers in your cab flap about. Using a HPF cuts out those damaging frequencies and allows your amp to only produce the stuff you can actually hear. I've found that using a Micro Thumpinator enables me to get masses of volume out of a little Fender Rumble 100, easily enough for smaller pub gigs without blowing it to bits.