Why do you want to purchase another amp? That's the most important question. Second most important is how loud do you listen to your material.
Main System: SVS Ultra Towers - 15" custom ported subwoofer - SVS PB-1000 - Yamaha RX-A740 Aventage. 122dB @ 16Hz!!!
Computer System: Carnagie Acoustics CSB-1 - 12' Onkyo sealed subwoofer - Pioneer VSX-92 THX
Other speakers owned or auditioned: Aperion T6 - Ascend CBM-170 - Energy RC-10 - Wharfdale 10.1 - Arx A1b