Thiel Owners

Thielrules, your 3.5 performance is not normal. Perhaps Rob might supply guidance.

As you might surmise, I have been looking closely at the classic models to determine where to best expend resources for upgrades. A sad truth is that the 3.5 is old. Those drivers were modified commercial units and are no longer available. The tweeters and midranges are not rebuildable, but I believe Rob can rebuild the woofers. The 3.5 dates from 1988, so early serial numbers are approaching end-of-service-life for the electrolytic caps in the EQ and XO. Those are replaceable.

After considerable deliberation I have decided to not develop an upgrade kit for the 3.5. There are too many disqualifying factors recommending against spending significant money there. However, Rob at Coherent Source Service can help you keep them in service in stock or enhanced stock form.

I've never heard the Thiel 3.5s (that I recall) but used to listen to the 3.6s here and there, though many years ago.  So you have to take any comparison I'd make with a big grain of salt.   That said, I also lived with the big Thiel CS6 speakers for a while too, so I have a pretty good bead on the Thiel house sound in general, I think,

Whenever I listened to the 3.6s "back in the day" my impression was always consistent: a sense of accuracy, in terms of tonality, soundstaging, imaging and a sense of life - great transient quality and an overall sense of control.  There was a real confidence, a sensation of "hearing the recording for what it is."

The slight knock on the 3.6s was, as many have said before, to my ears a teetering toward brightness and a tad bit of hardness.  Just a tiny bit of a "ruthless" quality.  Not as bad as that sounds, but just tipping a bit in that direction.

The other is a slightly "reductive" quality that I tended to hear in Thiel speakers.  The density of the imaging had the great result of palpability, but it seemed the Thiels could squeeze the sound just a bit too tight, with a signature that to my ear could seem to slightly remove the amount of body and heft of the sound of voices and instruments.  (The smaller woodwinds, for instance, could become fairly thin sounding).

The CS6 speakers I had, while sounding huge overall and full from the upper bass down, also had this slightly reductive quality.  Though I found them not bright at all, and not in to the ruthless territory so much.  They sounded gorgeous with my CJ tube amps.

The difference I find with the last flagship 3.7 (and to a degree the 2.7) is that I do not find any of this reductive quality.  Voices and instruments sound smooth, big, even and as lush as one could want.  If you have an acoustic guitar recorded up close it is BIG and full.  The sense of image sizing and soundstaging goes beyond any Thiel I had heard before.  And the tonal balance seems completely smooth - missing the slight hollowing sensation I could occasionally hear in previous Thiels.

And they have a more open and delicate way with fine detail.  
While giving you that aliveness, snap and image density and specificity that Thiel is known for.

So to my ears the 3.7s take the Thiel sound and simply refine it.  

As I've pointed out in my other, long speaker audition thread, despite listening to many of the best contenders now available, I did not find any that seemed to do it all as well as the 3.7s.

to reiterate the point that Prof made,   i recently listened to a pair of 29K Magicos driven by very nice VTL tube amps.   was it great?  absolutely.  was it better? yes as it was more articulate and had a overall cleaner sound.  however, when i came home and played my PS Audio system with 3.7's,  i was totally happy.  the fact that a 10 year old design could hold its on with a current SOTA speaker at over twice the price says something about the genius of Jim Thiel and his design team. 

Thiel rebuilt both of my 3.5's midranges in the fairly recent past.

Thanks Prof, really appreciated. I checked with Rob today and he has sold a lot of his inventory and all his 3.7 were reserved. He could not account for my measurements but indicated that he could rebuild all the drivers, XO and they would be good to go for about 1K each.
I have not heard any evidence of any drivers malfunctioning so I'll first double check my measurements and let him to do troubleshooting.
Unsound, did you notice a notable difference after the rebuilding?
Well, will take it one step at the time.