Thiel Owners

I was at least able to verify that the original caps are indeed Clarity Caps SAs as I am almost certain that this is the first re-cap these 3.6s have ever experienced

You must have very late production 3.6s. I would have guessed Thiel stopped making those before Clarity introduced the SA. Interesting. The SA is a good cap but, as Tom Thiel wrote, the CSA is a step up. The CMR is supposed to be even another step up. But those are much larger, possibly requiring a new board to accommodate their size and much more expensive. My new boards have 630V versions of CSA on the coax feeds. It would be interesting to compare 630V CSA to 400V CMR. There is a 630V version of CMR but those are bigger still and more expensive with a smaller range of available capacitance values.

You probably have high quality coils but I would replace any sandcast resistors with Mills MRA-12s.

Jim never went over 100uF.

Pic of @vair68robert coax crossover has a 400 uF EL. I know this crossover was designed after Jim passed. I imagine he will need to use an entirely new board if he chooses to replace that cap (plus a couple of other ELs visible in his pic, presumably >=100 uF). That would be quite the volume in film caps! But possibly worth it . . .

Let me chime in as some one with relatively recent experience with Clarity and CMR in particular, but not with Thiel rebuilds.

The CMRs are excellent caps. I honestly don’t know if they are better than the previous generation. I’ve swapped them out in my application and they sounded equally excellent.

What I have found in both cases (CMR and MR) is that Clarity caps above 5uF benefit from a small bypass copper cap. This was a suggestion passed onto me at DIYaudio by Speakerdoctor before he passed (RIP). Though he did not suggest it above a certain uF value, I have found this to be about the break point. Below this value, a bypass cap did not help, but above it certainly did.

Based on his suggestion I’ve used Audyn 0.1uF TrueCopper bypass caps, and they worked really well. Anyone who wants to ship me Jupiter caps instead please do so! :) I wish I could afford them.

Best,

E

@beetlemania

You have seen one of my obstacles ,
one possible option is 2 Solen 200uf 400v large
but the 400 is at the bottom of the board ,
Another is a Clarity TC 400uf 400v  very large .

I'm going to have to do a lot of measuring 
this project is going to take a lot longer than anticipated
as well as way over estimated budget ,
but after rehabbing 2 100 year old buildings with 5 apartments 
I'm used to being over on time and money .

Hey @vair68robert

Given the cap sizes you are talking about I'm assuming these are in low pass sections, and going to ground. The Solens, or their cheap brand, Axon, will be great choices, BUT, you must maintain the original ESR + R of that portion of the circuit or you may suffer unexpected impedance issues, which causes your amp to suffer, along with changing the crossover points.

Save the top-end caps for caps that are in series with the drivers.

Best,

E