Hello folks. I've been scanning this thread as time permits but life is short. By way of introduction, I was a founding partner and for the first 20 years was the director of manufacturing of Thiel Audio. I was intimately involved in all aspects of product development and company-building. I hope to contribute some elements of perspective to this conversation, especially where speculation lacks sufficient knowledge.
I want to clarify Jim's attitude about passive parts quality. From the beginning in the mid 1970s, we became very aware of the subtle but significant improvements via better parts. In fact we were an early innovator re film caps and bypassing with small values of better caps. We introduced long-crystal, six nines wire for our air-core inductors to the industry. I'll spare the details, but Thiel understood that landscape before it was considered an issue. So, the speculation that Jim was strictly a measurement-guy is incorrect. The reason for less-than-best caps is that they can be cost-prohibitive for highest value per cost engineering.Thiel was always about finding the optimum point on the cost-performance slope so that real music lovers could afford our products.
Regarding the measurement tells all idea, we found our way via intense, systematic, long-term music-listening and then Jim engineered solutions that had to also pass scientific rigor. Once the understanding about any particular issue was in place, the measurements contained the information; and the chosen solution was always closer to the scientific optimum. We could see the results of our work in the measurement data, but the converse was not true: the improvements could not be made predictively via the data. By the way, Jim designed and built test equipment that was way beyond what was being used for the purpose.
On the issue of hot-rodding existing Thiel products. I wholeheartedly recommend it, knowing the value / cost parameters of Thiel products. Rob hopes to offer upgrade services. Madisound is also a resource. I upgraded my (original 1989 prototype) CS2.2s with boutique signal-path caps. Wow. Keep in mind that the original caps were all carefully chosen for type, geometry and manufacturer and often bypassed by even higher grade capa. So, don't indiscriminately change everything. The best bang for your buck is in tweeter feeds. Note that (real) Thiel inductors are air-core (contrary to someone's post) and the wire is as good as it gets. Resistors are likewise selected to be very good. But improvement can be made there also. Solder is silver/tin, which requires more care than usual. Hookup wire is six nines with teflon jacket and proper twist density.
Another thread here has been the electrical vs acoustic first-order crossover. By "acoustic" Thiel simply means the net resultant system performance. That final slope of that driver in that cabinet with that insulation, wire lengths and other factors including eddy-currents, reflections, propagation distortions and other factors . . . all end up on a slope of 6 db per octave to produce a phase and time coherent crossover that passes a square wave and/or impulse - intact right through the crossover frequency. That fact of coherence allows the ear-brain to consider that signal as real rather than as puzzle to be interpreted in the fore-brain. I mention that because small system changes are more easily heard in a first-order system than in any other system. So, when you change caps, resistors and the like, be careful not to inadvertently change system parameters. As an example, some types of resistors exhibit different induction and capacitance than other types. Some capacitors exhibit different induction . . . and so forth . . . everything matters.
Take care with your upgrades and I believe you'll be amazed at the improvements in rendition of subtle detail.
To close, be assured that Rob is doing his best to ensure the best care of all you supporters who kept this little company producing these extraordinary products for all these years.
Best regards, Tom Thiel