I have a Mesa Walkabout Scout with the 12 inch speaker, cab rated at 4 ohms. I found a 15 inch cab, also rated at 4 ohms. Can I put these two together in parallel and just keep the master volume lower to avoid cooking my beloved little Boogie? Or will the fact that it is operating under 2 ohms total impedance just generate too much heat regardless? Thanks in advance for any input.