Thiel Owners

Thanks for the feedback everybody. I really do appreciate it. I think that I’ll attempt to further isolate the problem by swapping the tweeters first and then the midrange drivers if the problem doesn’t move with the tweeters. I’ll share my results with everybody. Tomthiel’s response is encouraging. I actually think that I stumbled onto something rather unique with respect to the CS3s and my small acoustically treated room. I was actually able to tame the bass by not using the bass equalizer and adding another set of 4’ x 2’ absorption panels (1 on each side of the room) between the corner trap and the first sidewall absorption panel. After doing that, I was blown away. It’s sad but at least I got to re-realize how special Thiel speakers really are. To make matters worse, newer Thiel models don’t have a bass equalizer that I can remove and the impedance curve drops to 3 ohms on some of them, which might present additional problems for my tube amps. I believe that the CS3s are 88dB efficient and the impedance only drops to 4 ohms. Good luck tomthiel. I know that Thiel owners of the world are rooting for you.

I think it not improper to point out that JA seems to hear what his measurements tell him. At 50" there is a midrange suck-out and some spikes. Notice that he wonders in print if that is what he is hearing.

Supposedly, Stereophile’s reviewers do not see the measurements until after their subjective evaluation but easy to imagine that JA might deviate from that when he does the evaluation *and* measurements. He does acknowledge, in this case, that the measured suckout is specific to his axis and distance. That said, it seems possible that JA *was* hearing with his measurements. Soundstage measures at 2 m. The CS2.4 has the flattest “listening window” of any speaker in their database (+/-2 dB from 33-20k).

http://www.soundstagenetwork.com/measurements/thiel_cs24/

It’s plainly obvious that JA’s 50" distance is inadequate to characterize the frequency response of a Thiel. I suspect the waterfall plot would also be cleaner if taken at 2 m (it's already quite good, especially in the midrange where other, larger drivers continue to have energy after the music has stopped)

https://www.stereophile.com/content/thiel-cs24-loudspeaker-measurements

Thanks for the link, holco. I quite like the subjective reviews at hifi-advice. They do an exceptional job of comparing the DUT not only to competing products but also describe how the sound changes with different speakers, even cables. Here is their review of the VX-5 (the amp section of my AX-5 is a less powerful version of the VX-5).
https://www.hifi-advice.com/blog/review/analog-reviews/amplifier-reviews/ayre-vx-5-twenty/

Utrak,

Check out all the absorption I have to use to tame the bass on my CS3.6s....panels and tubetraps.

https://systems.audiogon.com/systems/6163

Jon

Utrak - your room is small, but its proportions are very good, plus you get bass room gain without supporting the deepest and most problematic frequencies. Yes, they are quite efficient and the impedance doesn't drop as low as newer models, plus the sealed bass is less reactive and more coherent than higher-order ports and passive radiators. Sweet. You have kicked me into roping the CS3 into the 3.5 upgrade project. 

Story time: You all may or may not know or remember the deep recession of 1982. The Stock Market tumbled, expendable income plummeted and the emerging high-end industry took a hard hit. Many manufacturers including Acoustat (and I don't now recall other brands) went under. Many manufacturers dropped out of the June 1983 CES in Chicago - which felt like a ghost town compared to prior years. This was our 7th CES (before Las Vegas began), we had yet to make a profit, and we knew we were gambling on a flagship. The concept was the same as the 03 / 03a / 03b, but the execution of the curved baffle, highly customized drivers and next-level XO components put it in a higher league. We hoped folks would notice.

There was always a pre-show walkabout the evening before opening. We had a mostly European purist recording following who always brought master-tapes and headphones to compare notes from studio to showroom. The Danes had been to KEF's new Reference 105 demonstration, claiming "phase correct" presentation. They also did their homework and reported the drivers as being time-aligned, but using high order filters and scrambling their test tracks.

After the niceties, the new works began rolling. Lights out. Spaced omni capture of a live jazz ensemble, ending in a barely-audible triangle tink. It faded forever. Long silence. Applause. And the night went on somewhat like a dream. 

We had come to the show with a tentative retail price of $1250 / pair, a little advance from the 03a at $1150. We, especially Jim, feared a glass ceiling for a dynamic speaker from a fledgling, uncredentialed company at $1,000 / pair in 1983 dollars. These were frontier days, not only in Audio, but in boutique manufacturing generally, and on the heals of the deepest recession since the great depression.  Uncharacteristically, I surveyed the attending guests, about 30 sophisticated insiders and industry associates, asking what a proper price might be for this thing. The 'auction' suggested $2K - $5K. Everyone was elated.
We stayed up half the night discussing everything: the nature of our niche, the disparity between a few deep fans and 'the market' at large, the times, and the real settled costs of putting this thing into production. Note that each baffle was hand-sculpted by yours-truly in what might be called shop-jujitsu. We were pulling this thing out of our hats. Big sales were the enemy of stability and sleep. One key equation was that if I were engaged in hiring, teaching, coaching and managing new cabinet makers to produce this complex cabinet, I wouldn't be available to make baffles. Production is not prototype and we needed production to break into profitability and survive.

When the room quieted around 3:AM, we had decided to introduce the 03b at $1850/pair. 03b? Well, it was the third version of the 03 and our system assigned that name. Jim predicted that we would loose most of our dealers, since our niche was unbelievably inexpensive / unexpectedly good performance.

Next morning before opening, Peter Moncrief of The International Audio Review came to visit - he had heard talk. He was full of the right questions. He got answers he loved. He listened. He smiled. Peter pronounced that we had found the holy grail, that we had created the illusive and rumored impossible "Coherent Source" transducer. We christened it CS3 - Coherent Source, third generation model 3, and had the show of a lifetime. The room was packed full-time. Comparisons to KEF and B&W were flying. Only one east-coast dealer dropped our line - and was replaced by a more appropriate player. The CS3 turned our tide.

Was it a bugger to make? Yes. Did we struggle to meet demand, yes. Did we rise to the opportunity? Partly. The CS3 was our watershed. It caused me to take a huge plunge and adopt CNC machining in its infancy - as a first-tier user. We mortgaged everything, and still couldn't manage the $6-figures investment. Banks had no money to lend even if we might qualify.

Then magic happened.

Remember Scott Estes, the Maggie Man reviewing for The Sensible Sound? Scott had become a friend. Kathy and I were commiserating with him about the bucket-load of orders we couldn't fill, the back-order that could bury us . . . and he volunteered news of an unexpected inheritance which he was willing to lend us on the strength of his belief in us. Oh My God. He funded the critical corner, the one that might not have been navigated. The CS3 real-cost equation required a price increase to $1950 at the first Las Vegas CES in January 1984. And that was just fine with everybody.

Of course new learning superceeds old performance and new products always perform better in some ways. But nonetheless, the Thiel CS3 is a true classic in our corner of the history of the development of American High End Audio. And I hope to find a way for it to live on. R is for Renaissance.