what's kind amps & preamps for speakers aud-72 ?

Dynaudio's Audience series demands very strong amplification. I had the Aud 82, with another woofer, and they really took all the power my Bel Canto Ref1000 mkII could dish out. They rocked. Great bass. They exhibit a rather low efficiency (87-88) and a low 4 ohm impedance. The problem is a difficult-to-drive phase angle. I read something about it in a review/specs report. Your amp must have lots of damping power to control the woofers in the speakers. The tweeter is awesome, the mids are OK. I felt the Audience gave me an amazing sense of PRAT, fast driving, responsive, taut bass (a friend called it "dry"). I tapped my feet alot, and they were pretty easy to set up in the room (16x17) due to the small footprint. I listened to a wide range of music on these and they did a great job. I have replaced these with Von Schweikert VR4 SR mk 2 now. I think the PASS, Parasound Halo, Brystons, Krell, Mac, etc would be want you'd want. Lower prices--maybe some older Threshold or Forte amps, B/K, Acurus, Rotel, etc would do well (but need 200 wpc min).

PS, you cannot bi-amp the Audience speakers, a drawback since you have a multichannel amp now that you could use to give more power to the high/low.

Oh, now I see you need a m/c amp, not 2 ch. So substitute the equivalent m/c model for manufacturers I list above. I have a Sherbourn 5/1500 for my HT but it's not musical enough. I'd go Parasound Halo 51 for this and not look back, or a Class D m/c solution like Wyred4Sound.