I have a stock Hot Rod Deluxe, and It is too loud for me. The speaker in it is a " 12" 8 ohm fender reissue gold label (037617) " Does anyone know what the efficiency on this speaker is, or what another, less efficient speaker would be? Or would my trouble be solved by switching to different tubes, IE 6V6s? To my understanding, the Hot Rod Deluxe does not have a bias trim pot, so how would I go about using these tubes? Any and all suggestions are very much appreciated. Thanks in advance for the help.