A really easy way to slave if you have 2 amps with FX loops. The plexi' s FX send goes into the Elmwood FX return. Both amps loaded. The advantage is you get one amps preamp characteristics with another amps power amp stage. In this case the Elmwoods power section is much cleaner and darker than the plexi so it smooths things out a bit, reduces gain and adds some compression. The plexi is 50w and uses EL34, the Elmwood is 80 or 90w and uses KT88's. I can also use the Elmwoods fat and edge (res and pres) for additional post EQ tone shaping.