Abery, I am wondering why Zu does not offer biwiring / biamping options. To be able to vertically, passively biamp your speakers, using a 2nd Sta200, would be, imo awesome. I am using my pair in another system, doing this ( although, admittedly, I listen to my main system, so much more than my other systems ). I know of a few, that have modified their Zus, to have done this. BTW, the statement made by Goldmund, stating the " competition " was fierce, was driven, imo, when Nuforce lowered the price of he STA 200, down to $499. Again, Goldmund, shot themselves in the foot, licensing the circuit out. They are likely getting residuals on the licensing agreement, I suppose. The circuit boards, their layout, the toroids, are quite similar, so factory of manufacture, might, or might not be, the same. Still, at the $499 price, a really nice, musical sounding amp, doing many things right. As I have mention on other threads, this STA 200, made it easy for me, to take an amplifier collection, of over 100 specimens, to now, about 20. Enjoy ! MrD.