I Need a Power Amp for my Studio Monitors

I've got a pair of JBL 6332 studio monitors in my home recording studio and need a sufficient amp to drive them. I noticed that a lot of studios use Bryston amps, but I also hear a lot of people saying that they're "unrefined" in the mids and high end. Any comments about this or suggestions? The 6332's "nominal" impedence is 4 ohms.