These comparative observations are quite interesting to me. As you know, Jim developed new technologies throughout his inventive career. Each new product incorporated something, or multiple things that were brand new. So the timeline becomes a parallel consideration to the model capability. Bigger, more expensive models bring greater dynamic range and deeper bass. More drivers can deliver better signal integrity spread more evenly across the musical range. The time factor / when the model came out, brings subtlety and sophistication due to new solutions, primarily in driver subtleties, especially after Thiel began making its own drivers in the mid 1990s.