Joshorr:

Another way to hook up a tube preamp to the 950 is have to get a preamp with a theater or processor loop. This is the simple way, just hook up front left and right pre out of the preamp to the Power amp channels. Then run the loop to the main power inputs on the 950. The loop will bypass the preamp and send the power amps hooked up to the tube pre amp directly to processor. You would have the tube pre hooked up to main L/R speakers. When listening to 2 channel you will use your tube pre amp to the source. and leave the 950 off. Many tube preamps now have the processor loop and even some integrated tube amps. Anthem, Sonic Frontiers are still around and warrenty is honored by Anthem (I have an Anthem Pre 2L with the loop that I going to sell to get a Cary). Cary, Conrad Johnson, VTL, Plinius, and I believe one of the Jolida models have loops. That is just the ones off the top of my head. Many SS premaps also have the processor loop and can improve your 2 channel enjoyment when hooked up in this format. Good Luck