I have several guitars and amps, but whenever I'm trying new pedals and I want to hear what they really sound like, I always head straight for my Blackface Princeton Reverb with my Tele. This is the perfect canvas for me to hear colors. Because my ear is so accustomed to this sound, it's become my "blank slate" and I can hear the true measure of anything I add to it. I have other guitars and amps that I love just as well, but this is the set up I use to audition pedals when I'm really trying to hear what's going on. I'm wondering if anyone else has their own Tabula Rasa scenario.