Looking to upgrade my current Pioneer SX-950 receiver, and had come across the idea of using a separate amp for each speaker. I am currently looking at a pair of NAD 2155s, as they seem to be well respected and are in a good price range for me, and realized that when operating as monoblocks, they put out a decent amount of power. What are the gains to be had in doing this versus upgrading to a preamp/amp combo and just running a typical setup? What is the preferred way of tying the amps together, operating them with a preamp/receiver? I apologize if the questions seem basic, but thanks for helping to educate me!