Thiel Owners

Andy - regarding diffraction - please pardon me not knowing its controversy, I've been out of the loop too long. It is not controversial nor trivial, it is a fundamental element of design; it is measurable and directly hearable if the system is transparent. For yourself, or with a friend, listen to yourself speaking or singing. Then put your flat hands beside your mouth and repeat. The difference you hear is diffraction.
However, there are cases where diffraction is masked in playback. Since diffraction is a phase-time anomaly, those systems with compromised phase-time performance might mask its presence or conflate diffraction with the other phase-time puzzles requiring mental reconfiguration. 

Regarding baffleless drivers vs rounded baffles. We experimented with both early-on. Both have their merits. However, the baffleless concept treats the individual drivers as separate units with their own diameter to wavelength behaviors. The rounded (Thiel) baffle treats the unified radiating soundfield as a whole. On balance, I believe (as I would . . . duh) that the unified, rounded single baffle does more things right; its major flaw being increased cost.

Looking to natural acoustics, the mouth or musical instrument forms its soundfield across its entire frequency band, not as separate sources for bass, midrange or treble.

On to the greater concept of controversy: most controversies have little to nothing to do with the subject under scrutiny. They have more to do with the biases or knowledge (including deficits) of those arguing. So much would become so much clearer by using the correct pronouns. When someone says "you can't hear it", I believe they are actually saying "I can't hear it". Fair enough, except that they are projecting their lack of hearing on "you", which includes you and me and everyone else who is hearing it. In my experience, that projector has rarely if ever actually tried to hear the difference being denied, or at least not objectively analyzed and explored the territory. Imagine if you or I were so bold as to tell a conductor or band leader or competent recording engineer that "you can't hear it". If he didn't slap you, he would either dismiss you or ignore you. We earn our keep by hearing it and understanding it and making it better. End of rant. 

Prof - the 02s were made from standard-grade stuff, miniature, standard electrolytic caps,5w carbon comp resistors and normal coil wire. The system will often work with bad parts. At nearly 40 years old, the caps are almost certainly shot, unless they were replaced over the years. Other parts could be OK unless you boogied too hard. The non-technician's look-see is to remove the woofer, shove the insulation aside and see if anything (caps) looks like the 4th of July. 

Yes, I am upgrading at 3 levels: 1) better basic parts (no electrolytics), stabilized coils (varnish and bake), new hook-up wire and jacks, reworked grille to reduce diffraction. 2) add upgraded drivers ( possibly Thiel CS0.5), Mills resistors, better caps including CSA tweeter feed, 3D grille like CS1.3) add sweet passive parts, double jacks, foil coils and sexy golden ellipse cabinet edges front and back. Concepts to be developed in 02 for use in all models. 02s are a very manageable sandbox.

I have to find some more pairs - please keep me in mind.

Unsound - right on! In fact, the model 2's reason for being was conceived as just that - create a huge bang for buck product utilizing technologies and parts whose development costs were amortized at the higher-end.

In the beginning . . . Jim was a very linear, no-nonsense engineer. He projected a 2-way, a 3- way, eventually 4-way, etc. The 3-way was the model 3 (a-ha!), so how to imagine another 3-way? We found merit in the smaller-driver, less bass, less balls idea and committed to allowing, even encouraging trickle-down. The CS2.2 utilized the tweeter developed for our statement CS5.  And so forth. Things got murkier as we developed more products for multiple markets. But indeed the model 2 is in its soul Thiel's cost-performance champion.

If I may be so bold as to add to TomThiel's commentary on baffle size. Years ago I asked Jim Thiel why he didn't use a more tapered pyramid shaped cabinet to avoid baffle deflection. At that time he explained that only market considerations kept him from using more preferable to him even wider baffles. He added that the wider baffle area would provide more consistent sound for the end user, as a narrower baffle would then put more emphasis on the listening room, which would in turn make the sound output that much more unpredictable.

With respect to unsound post regarding to baffle size, not to say which one is the most "correct", but there seems to be different design philosophies.  Sonus Faber makes a few very wide baffle speakers.  Thiel is somewhat in between with the curved baffle.  Vandersteen basically eliminates the baffle altogether for most of its designs.

In my opinion, the wide baffle has its advantage but it also has its disadvantage.  The wide baffle shifts the diffraction freq. lower, but then the problem is the low freq. image would suffer - that is the low freq. image would become "phasey" and shifting around and not stable.

I don't think you can eliminate diffraction completely.  It's a matter of how to control diffraction for a given speaker design.  

Just to show how the front baffle can affect the soundstage image, I found that (and most others) a small standmount monitor seems to be the best in term of "disappearing" since they have very small "sound foot print" with respect to the baffle size.  Most large speakers cannot do this as well as small standmount since its baffle geometry is much larger and inevitably will get in the way of the sound front.  

Anyway, baffle size, shape, and geometry will bring up different opinions and I guess different designers will have their own preferences.