Has anyone ever used "stacked" Heresy's

I think the Heresy makes for a great rock speaker as well. It also serves the rest of the musical spectrum quite well. If you do by a second pair, and your aim is to suplement the bass, you may want to put them side by side instead of stacking them higher and keep the bass drivers both low and close to the ground. Wonderful speakers, and an outright bargain for the money you pay for them for sure. I found a big improvement in swapping out the stock internal wiring with DH Labs Silver, and replacing the back with MDF. Also, at the same time, create some better seals around the drivers and the back of the cabinet. All this should enhance your bass response to a small degree. I'd agree with Sean..if you do want to go lower a sub would be the answer. I prefer the older (original) version with the heavier cabinet, as opposed to the Heresy II model which is about 8 lbs lighter as I recall. Drivers are different, as is the crossover as well.

Marco

Regarding bass and the other Klipsch products Mechans mentions: I'd agree that you'd get more bass from the Belles and especially from Forte II's, but it has not been my experience that LaScala's product low bass (and I have owned two pairs). To be fair, I have not tried biamping them though as Mechans suggests. My assessment of them with various tube amps is that they begin to fall off at around 50hz and produce very little below 40hz. I've also owned two pairs of Forte II's which are less refined speakers, but excellent rockin' speakers and most definitely go lower. I've heard Belles only in a friends system and was impressed by the added bass over the LaScalas. Perhaps I oughta try biamping sometime. I imagine the issue there is keeping the spectrum in balance though.

Marco