I'm kinda thinking upgrading your amp and using it with your Outlaw prepro is a bit of a mismatch. If 2-channel is important to you I'd consider getting a better stereo preamp and use that to drive the Bryston (or whatever else) and let the Outlaw do the rest. You may find the improvement of a better preamp might make living with your 4B fine for a while, and then you'll be in a better position to upgrade your amp later. In my experience preamps can frequently have a bigger impact on overall performance than amps. Not that your Outlaw is bad, but it's not a Pass Labs, etc. Or maybe a better prepro if you don't want a stereo pre -- maybe something like an Anthem. Point is, the preamp is important and you might consider addressing that before spending $$$ on another amp. Best of luck.
