My second system currently includes a Dyna Stereo 70 ( GSI Triode Mod,which reduces output to 25 WPC )and it sounds great as long as I don't push it too hard. If you're going to use a pair of ST 70's,I'd strap them in mono rather than using them as stereo amps in a vertical bi-amp set-up. It will definitely work,but sound quality will depend on how loud you want your music. Good Listening Bob
