You may want to run your speakers off the 4 ohm tap of the ARC. Also, don't be so quick to blame the amp, interconnects and speaker wire play a huge role in the sonic signature of your system. Maybe your hearing your system for the first time. Are you using older silver cables? When was the last time the tubes were replaced in your Ref3? Remember now that your system is resolving better, you need to be a bit more critical about the surrounding components that make up your system.
