Thiel Owners

unsound - Thank you for your point of view. It is entirely valid and I do not intend to recommend the Benchmark for the reasons you cite. But my task is to find source and process equipment that operate at the edge of serviceability rather than big, bulletproof, proven amps which are known to be great. Dealers that succeeded with Thiel generally used Krell FPB-600 or Big Levinson / Ayre etc. etc. You guys know what works. I know that those will all work better with my designs. I must find solutions to the larger problem of most amps not working well enough with Thiel designs. 

I am hoping to mitigate what I judge as somewhat misplaced design focus on Jim's part. He considered amp performance as amp-maker's problems and if an amp can be found to drive his speakers, then there is no problem. A disconnect that I see includes that the internal hoops we jumped to keep prices affordable were overshadowed by the costs of suitable amps. (Indeed those amps can now be bought used for less. Good.) I am working on the assumption that those amps will perform well without my intervention. My mission includes implementing design strategies that produce great performance with less than ultimate amps.

One such strategy is the particular bi-amp configuration I mentioned. I hope to prove a cost-effective way to drive Thiel's brutal loads with less cost than big iron amps. I want a very different amp than my classic Classe configuration. I will final test with Rob's FPB-600s among others. But I also want to see what I can get with a pair of affordable new world amps costing less than $3K new.

unsound - you are right. There may be some backlash. But we here are an insider beta group sharing a development process. Indeed we will test at full power. BUT everything we are doing will improve performance at high power. That end of the use spectrum is not my concern. My concern is getting maximum bang for the maximum head count from the upgrades.

Someone asked for a list of amps which I have dismissed. I don't have such a list. I read widely and systematically. I know that amps color the signal and how that generally works. I look for clues and attitudes in reviews and user comments, and add that to my personal experience. I know that if I use tonally and temporally accurate equipment with well made source files that my results will be valid. I am looking for the needle in the haystack and have not itemized the haystack.

Beyond amps, I am using Klippel and SpectraFoo Phase Torch and signal analysis gear. I know symptoms from square wave behavior and am familiar with measurement vs listening protocols; I helped develop those protocols at Thiel. Jim went on to amass tens of thousands of hours of experience correlating data with listening. I can't claim that. But I do know the territory, including considerable live and recording experience beyond what Jim brought to the table. I am taking an alternative perspective.

I'll be straight with you guys. I do not have the financial means to buy a dozen amps for comparing and proving. I must choose some tools within my means which tell me as much as possible about what I am doing and where I am going. As the project might gain momentum, I might get access to amps on loan, etc. (For reference, at Thiel we always had more than a dozen amps on reciprocal trade from top manufacturers.) I hope that JAFant or others of you might create a recommendation / dis-rec list from your considerable combined experience - beyond the conversation we have been sharing. That list would provide a huge service / reference to the 4000+ members of this forum.

Off for now. I'm running sound at the Open Mic at our Village Arts Center.
Next week the Piano Guild is testing my alternative bridge in their project piano. The piano, the guitars and the speakers all co-inform my understanding. Interdisciplinary Boogie.

jacob - we don't yet know what form the upgrades will take. One complicating factor is that Thiel crossovers since 1990 / CS2.2 use silver/tin solder which requires technical know-how. We will probably have a first-level upgrade of critical caps and all resistors that the adept user can implement. The higher levels are completely new layouts and will probably come as new boards with probable instructions for added cabinet braces and other tweaks. Too early to say. I know I shouldn't say. But, hey, you guys are family.

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.