Very clever design for playinng direct. I use it at our church. You get 3 channels voiced, eq'd, with gain and volume each available with a dedicated footswitch. I also find it takes and OD pedal in front of it well. I disagree with comment below about the construction quality. It is a very sturdy design, cast aluminum. Not as tasty as a true tube amp, but I tested many modelers and what-not's and this stood out best.

I bought this pedal because I was playing through the system and it was recommended by a friend who had owned it before. I used this pedal more than my ds-1 now. It gets great tone wether you are using a light distortion or a hard crunch. You can blow your PA so be careful of your volume when you plug it in.

I use this into the effects loop return of my Mesa Boogie Mark III, INSTEAD of using the pre-amp of the Boogie. Nuff said.

Makes my LP sound like and LP, and my Tele sound like a Tele.

4 stars on quality because the box is constructed of flimsy sheet metal. Had they put this into a real enclosure it would have been perfect!

I've had this pedal for nearly 10 years...Overall it's amazing...does everything it claims.

I use it primarily for Tweed-Blackface and Silverface-HiWatt tones. As a preamp, it does exactly what it should. And the big surprise, for me when I bought it, is that when you use a single channel tube amp and want more, all you need for three or four channels mayhem is the Tri-AC.

I guess, I'm smitten...wouldn't ever get rid of it...and as for quality construction, it's outlived more than one, "professional, durable pedal-board."

My only criticism is: depending on application, channel volume and tone will differ (and I don't mean a standard change across all three channels...that's a "duh, really?" kinda thing). What I mean is: if you use it both as a preamp and as a distortion box expect to reprogram it regularly. If you’re especially bright, you’ll even learn to write down your settings when you find the ones that work best.

As an amp modeler this pedal is worth the money. Doesn't take much to change the sound either. Slight adjustments on any of the 5 knobs (drive, bass, mid, treble and level) can alter tone significantly.

I don't use it as a distortion pedal. Better dirt pedals out there. I use my own and keep the Tri AC drive in low just enough to kick in the amp tones. Really nice. Now I'm interested in Sansamp's new character series pedals cause I think these guys nailed analog amp modeling.