I scored a replacement midrange driver for my 3.5s by placing a WTB ad on Audiogon. I soldered it in and voila! no perceivable change even though the mid driver I replaced had three holes on the surround. Since I thought the speakers sounded fine even before I started looking for a replacement there was no surprise. I will send the wornout driver to Thiel when the other one starts to fail. That way there is no down time for the repair. Now that I have the equalizer out of the circuit the other| driver may last forever.
By the way I've noticed a slight narrowing in the sound stage without the equalizer and a little better focus in the image overall. Everything involves a trade-off. For the moment I prefer the extra clarity in the sound to the slightly smaller stage. I have tube electronics so the highs are still smooth.
I also added a little more bass back in the system by raising the woofer crossover point. It may not measure as flat at my listening location but it moved the bass response closer to the original.
