I'm probably going to be replacing both the 12s in an older, heavily modified Tech Soundsystems (forerunner and similar in design to a Schroeder 1212) cab. The speakers still work fine, but I've used them hard and they are starting to breakup a bit. Plus I've recently discovered the Techs are 4 ohm speakers and had been wired parallel (2 ohm load) which isn't optimum for a crossover that wants to see a 4 ohm load (I switch them to series as the crossover is handling the 8 ohm load better). So....opinions: Which 12s would you suggest? (PS. Must be 8 ohm so I can get a 4 ohm load in parallel).