Thiel Owners

Prof, . . . you can keep your 3.7s and join the upgrade brigade for even more musical satisfaction.

@prof Tom Thiel is learning much about the late model Thiel crossovers as well as how to improve parts quality for all the models he is now working on. You might hold onto those CS3.7s another year or so and try his upgrade when it becomes available. 

@beetlemania   

Q:I’ve never heard ATC. Maybe they’re onto something? But I’m skeptical. As Tom Thiel wrote, the steep filter lets you operate a driver in the range of pistonic behavior. This is *highly* desirable (and also requires diaphragm material up to the task). But this throws off phase coherence. There is no free lunch. If there were, all designers would hone in on the same design.

Thiel Audio placed phase and time coherence as a top priority. The downside is that the slow rolloff may not sufficiently suppress the inevitable break up modes. As I’ve written in this thread, I think Jim Thiel made some of the best drivers around. The diaphragms are light and rigid and the break up modes are out of the "main" region covered by each driver. Even at that, some may consider the break up modes insufficiently suppressed by a 6dB filter. Richard Vandersteen seems to have taken this even farther with his carbon/balsa drivers but you need some serious coin to move up to those. The carbon midrange is available only in the 5 Carbon ($30+K) and 7 models ($60+K). 

IMO, most of the newer Thiels get it right in terms of balancing phase alignment and pistonic behavior (I’ve heard CS2.4, 3.7 and 7.2 but not earlier models). My ears tell me so, and Soundstage’s measurements of the CS2.4 confirm "very low" distortion despite the 1st order filters. Nothing is perfect but I think Thiel gets you most of the way there and at an affordable price.

That said, if ATC or others have figured out how to maintain phase alignment while also optimizing pistonic behavior I’m happy to learn!

Yes ATC driver integration is perfect in phase. Active has huge advantages over passive - no lossy crossover and also far less intermodulation distortion as each transducer is driven by a separate amplifier. Top studios (where your music is produced)  have almost all been active for the past 25 years. So far this hasn’t tricked down to the high fidelity market much. Dealers substantially benefit from the need for complex, costly and powerful amplifiers necessitated by loading a power amplifier with several transducers and a lossy crossover (usually a highly variable impedance curve).

That said. Thiel is extremely good despite the limitations of a passive crossover.

tomthiel,

My problem with my 3.7s isn't sonic; it's aesthetic and ergonomic.  Aesthetic in that they are visually just a bit overwhelming in the room (though I love their design).  And ergonomic in that they must be placed in a way that impedes traffic flow in and out of the room.

Sonically, in my room they are as perfect as I've heard in any loudspeaker anywhere, in terms of not showing any obvious room interaction issues.  My room was an expensive re-design employing an acoustician in the design - bass treatment etc is built in to the room, and I can alter some of it's reflective characteristics easily for higher frequencies.   The 3.7s sound completely linear and controlled.

But....they just don't work in terms of size...such is life.

The 2.7s I picked up are a very nice consolation prize, though. :-)

Pass Int 250 or Gryphon Diablo 300 to drive CS 3.7
Which one has the right sound signature for Thiels ?

You are certainly on the right track for top-tier integrated amps -thieliste
staying tuned as you sort and demo those contenders for your system.

Happy Listening!