Matman,

You have a nice set up there.

I too am using the AVM 60 preamp and like it very much. I feed it to the Parasound A51 with 5 channels. I use two channels to the left and two to the right Bryston T's, bi amping. Each channel at 4 ohms is outputting 400 watts. The dynamic power of the T's fills this 10,000 cu foot room very well, but Its so large that I need subs to round things out. Thus far, the EP500 is holding it's own. I am sure you are right, a second one would really do the job. But I cannot keep from wondering if the second sub was to be the EP800, how would that effect the over all balance.