My main rig is a TH500 and two DB112s. I love the tone 99% of the time. BUT I might understand what
@shadven means when he says his experience was that it sounded terrible.
Back in November I used the rig for a venue of about 1,600 - 2,000 people. It sounded terrible. I couldn't hear myself at all out of the cabs. I guess the noise level from the guitar amps and the monitors were so loud I couldn't dial a good tone.
Now I must admit that particular band's stage sound was annoyingly loud, and to make matters worse all the musicians were anything but distributed throughout the stage. Up until that event I thought that my pair of DB112s combined with the TH500 would suffice any venue. Definitely not. From what I've read though, the TH500 can power a 1x12, an 8x10 and anything in between pretty well. So my answer to the OP is perhaps the TH500 is powerful enough, but look into something bigger like 2 4x10 cabs, a 4x12, a 6x10, or something that will push more air than my pair of DB112 cabs.