Thiel Owners

beetlemania

Thank You for the confirmation.

Happy Listening!

For the record, wool acts quite differently than fiberglas, as does polyester fiberfill or spun mineral wool, especially in transition to the deep bass. Final placement and voicing of damping was always made by results. Listen to it, and if you have the means, measure the output smoothness. Insulation schemes will unload at various frequencies due to complex resonant behavior, especially in reflex systems. Fiberglas behaves more simply and predictably than any other scheme we found.

In my time, and possibly onward, the first reflection of the midrange driver off its rear enclosure wall was absorbed with dense pure wool felt - it worked the best for that purpose and its considerable expense was worthwhile. Our evaluation of wool batting for absorption was not as good as fiberglas.

tomthiel

Thank You for sharing your insight on loudspeaker insulation.

Happy Listening!

Thank You Tom Thiel

I wish I had known about the findings by Thiel
before I tried experimenting with wool batting ,
so with the knowledge you have shared I will give up any thought 
about trying to use wool , especially since the 2.7 doesn't have 
a seperate chamber for the midrange speaker .

Rob

Rob - I saw and heard the first pair of 2.7s at the factory in 2012. I believe there was an angled dividing board between the lower (woofer) and upper (midrange) chambers.
I should add a thought to the insulation riddle. Many people assume that wool is best, the other synthetics are next and fiberglas is worst, due mostly to cost, where fiberglas is the least expensive. I've previously mentioned that Thiel's fiberglas is a best of form type. I don't think that I've mentioned my reasons for confidence that it's pretty good, perhaps best for the task.
In the late 80s during development of the CS5, I took on the project of comparing, contrasting, testing and choosing an 'optimum' batting / insulation scheme for the CS5. Such research always trickled down to less expensive products where an as cost-effective. I had some pretty luck help. Toyota was coming to town with their Camry plant. Also IBM keyboard products was down the street and the University of Kentucky had developed a School of Advanced Engineering in support of Toyota's success. I've mentioned the happy quirk that Thiel Audio was a 5th member (of 5) of UK's Advanced Manufacturing Roundtable, to which I was Thiel's representative. Lots of stories there, but today's is that Toyota, of course, was bigtime in the sound deadening business as was IBM. In addition to picking their brains, I brought my cousin Teddy (the GE Jet Engine guy) to the party for his knowledge of aircraft noise abatement. Needless to say, there was horsepower in play. Less likely, is that the scheme we had originally developed in the late 70s won the day.

Many of the reasons for choosing other materials have to do with odor or fungus or handling or airborne particulates. Those issues were all manageable and wool felt and fiberglas is what we kept. There are many new subsequent products and concepts. Thiel never approached constrained layer damping or suspended case in case construction. But we did explore various surface damping schemes. I found nothing to make any appreciable net improvement over what we had. And it seems that future products kept on keeping on. Although I am investigating air movement and panel resonance, I haven't considered re-addressing the original wood felt / fiberglas batt chamber damping. For now at least.