Thiel Owners

Thanks for sharing the summary of the upgrade choices, Tom.

@rojacob if you successfully upgraded the coax feed caps to SE then I can’t think why you could not also build an entire new board. You must have taken the coax board out to access the solder joint underneath, right. So, you can solder and have experience working in that space. 

Building a whole new board is not any more technical than that, just a much bigger project! And I imagine Rob Gillum could also assemble the new boards for a price but this would still require the user to replace the extant XOs. But we’re getting ahead of ourselves. For the impatient adventuresome, you might proceed on your own with the clues Tom has shared. Otherwise, i suggest waiting for the kits. Some of the caps and coils are custom values unavailable from retailers such as partconnexion and sonic craft. For example, good luck finding a good quality foil cap in 14 uF. You can get the correct value by running caps in parallel but this adds to the size and expense plus could have negative sonic consequences.

Thanks, tomthiel & beetlemania for your info and vote of confidence. I actually did Rob's upgrade to the caps without removing the xo board, which is what he recommended. I did, however, release the board from the speaker case to do the work. The leads from the drivers to the board were very short and I would probably recommend others doing this upgrade to remove the board completely, even though one would have to reattach the leads and (perhaps) install additional lead wire.

tomthiel, I understand and appreciate your points. Please forgive me if I am belaboring the point. Although I would consider a modification that would allow bi-amping with my Thiel 3.5's, I suspect that might be due to the unique qualities of the 3.5's with their 4 Ohm nominal/minimum rating with not dropping below 5 Ohm independent testing, that opens the choices of appropriate multiple amplifiers at more reasonable costs, and of course as a way to restrict the influence the eq which applies to a few other Thiel loudspeakers as well. The special cabling required to make the Benchmark work with the eq's is not typical of how end users make connections. Some might be apprehensive to invest in custom cables that will have such limited alternate use. As such many might disqualify the Benchmark. I would think amps that have more universal appeal with all Thiel loudspeakers might be more advantageous. I think the idea to adapt Thiel's with more challenging impedances with bi-amping with modern amplification certainly has merit, especially considering what I suspect is a paucity of other options. On some level none of referenced speakers could be considered any thing like new, and I wonder if we should just accept that that ship has sailed, and just deal with it. Though appropriate amplifier choices might be limited, they exist and are often readably available.  At comparable
cost's; would two perhaps less capable modern amps be a better value than one capable one? Mixing amps can become problematic on it's own, doing so with first order cross-overs could make it even more complicated.

Indeed - mixing amps is extremely treacherous, which was the main reason, along with mixing cables, that Jim axed the dual binding posts. Good points about cables and special considerations.

I suspect the bi-amp advantages are not special to the 3.5. Amps constrict in various ways when high current draw surpasses the reserves. Vertical bi-amping supplies double the power and also sequesters the problem area to itself. In other words it makes more sense if bass overdrive results in distorted bass (sequestered channel), than if bass overdrive results in distorted treble (full range channel).

By the way, please push me. I am feeling this out as I go.

I think the Bryston 7b St with the serial and parallel setting represents a solid neutral amp that allows for regular and low impedance speaker comparison and identify issues due to impedance.