I'd suggest either the HK 990 that Kal recommrnds or a suitable pre-pro with a separate 2 channel power amp of your choice - if you can live with a 2 box solution. Many power amps will allow auto triggering, so operationally, there's little to no difference between these options. The separate pre-pro route allows easier switchover to video/multi-channel use down the road, if changing circumstances make that appealing.
Marty
Marty