Another classic pairing would be the Classe CA-M400 monoblocks. I've heard both the Mac and he Classe with them and would give the edge to the Classe monoblocks.
However, I would suggest giving the new Spectron Musician III SE Mk2 amps (600 watts@8ohms) some consideration. These can be made in monoblock format (two of them) also and would be my recommendation having this amp for my 803D mains and having listened to the aforementioned Macs and Classe. It is like combining the best of both of them. Very musical and liquid amp with tight and powerful bass. Only downside is run-in time of about 200 hours.
