unsound - we’re actively working on the 3.5. It is perhaps my favorite Thiel speaker in that it captures Jim’s primary insights. It’s the only place I’ve ever heard honest 20Hz, in-time bass; and with a footprint of a square foot and waist high.
Jim Williams of Audio Upgrades in Carlsbad has re-worked the EQ for substantially better performance. Bill Thalmann of Music Technology is mapping a fully balanced unit with a few more audiophile touches. Balanced will require an EQ unit per channel.
Low-level crossovers incorporated with the EQ is an excellent idea, but beyond my present scope. With the new (Purifi, etc.) switching amps, multi-amp drive could be heart-stopping.
As a historical note - Thiel’s first product that never made it to market was just such a configuration - small 3-way with built-in driver-dedicated equalized amplification. In the mythical revival department I think such a speaker could rock given today’s technical resources. Not for me, though.
Another note, the CS5 (1989) followed the 3.5 and could have been equalized, but Jim had become discouraged by the reactionary response, especially from sophisticated reviewers, and chose to get sub 20Hz sealed bass without EQ at the cost of 2ohm impedance at the bottom end. The subsequent CS3.6 in the early 90s became the watershed. Rather than developing an upgraded EQ to continue the model 3 tradition, Jim opted for reflex bass. It was properly implemented, etc. etc. but nonetheless diluted the commitment to phase / time coherence that had built the company’s market niche and reputation. I considered that a market-capitulation at the expense of root principles.
Imagine a CS3.5a using the 3.5 woofer and upgraded EQ, an updated version of the double-cone 3.6 midrange and an updated (CS5, 3.6, 2.2) UltraTweeter using the 3.7 / SCS4 moving system. I bet you’ll like it.