When I began this journey in 2018, I bought some including the SS2. I took it to Atlantic Systems, masters of repair and long-term warranty station for many high performance brands. Short story is that without schematics, they were unable to crack the code.
Regarding the code, Jim incorporated his proprietary boundary effects compensations into the amplification circuitry along with thermistors in the voice coils to boost power relative to heat and position. It seems that Jim kept all of this as proprietary and did all the repair himself at Thiel.
We need schematics to make progress. I don't yet have them, but I haven't given up hope.
If you haven't already, contact Rob Gillum at Coherent Source Service. Those woofers are special, they have coil and pole piece shunts and all the accumulated Jim Thiel advancements. They're also extremely durable and if they're broken may be repairable. Try to keep them.
Regarding amps, Rob says that eventually the Canadian 'Bash' company built replacement amps. That's about all I can say about the subs. They are the best I've ever heard.
