Good Subwoofer Amp

I have a decent system, I run 4 high box satellite speakers that are built with very high Dynaudio drivers, electronics etc. I also have 2 custom built subs, both closed system design. One running a custom 15" driver that cuts of 16db per oct at 40hz, and a 12" sub that handles from about 30hz to 250hz.

Anyway I have a pair of 7270 McIntosh amps to run the high end, and use a C-39 preamp. I was using a Carver 350 watt a channel amp bridged to run the subs. Well after 15 years it has decided to go south. What would you guys recommend as a good bass driving amp that does obviously need the clarity of a high end amp to drive the high frequencies, yet has a lot of punch . I need at least about 250 watts at 8ohm , 400 into 4ohms, or a decent 500 watt mono block, or amp with a lot of headroom that runs cool.

I would lost something that is not a bank breaker in terms of cost. I am very aware of many high end amps that would fit the ticket. But what is the feedback on an Adcom or similar amp?

Thanks everyone!