Thiel Owners

ish - I know those Hales speakers very well. I consulted for Hales during their development and compared 1st vs 4th order XOs. Paul is very bright and competent and pragmatic. The development time / cost / benefit and all adds up to 4th being "good enough because people can't hear the difference". Note from these impulse responses that the speaker is neither time nor phase correct. Paul didn't think it necessary. https://www.stereophile.com/content/hales-design-group-transcendence-five-loudspeaker-measurements

The sealed bass is awesome and Paul thought it embarrassed Thiel's reflex bass. OK. The sloped baffle was for the purpose of what your salesman executed in the store. The German who had resurrected Hales Design Group from the ashes of Hales Audio wanted SALES. By the way, the baffle was not concrete, but Hydrostone a fiber reinforced combination of portland and gypsum cements which I had developed for the CS6, but Jim substituted concrete after I left. Jim thought of "concrete" as the optimum enclosure material and Walter Kling who replaced me had an architectural/ builder background. Concrete lasted a very short time because it shrinks for 7 years and cracked at stress points. I doubt that Hales baffles ever cracked. Nevermind.

Hales frequency response is exceedingly flat and its component and build quality is very good. But it is a horse of a different color.

@tomthiel, my understanding is that the reduction in shrinkage is mainly due to the fiber.  Is that correct?  I've been wanting to build a madisound kit and make the baffle out of concrete.  I have the concrete, a bag of glass fiber and some plasticizer.  I went so far as to create the cutouts for the drivers.  I've got little kids so what would take a normal person a weekend will take me a year if I'm lucky.  I've been buying most of the tools I'll need slowly.  Main problem is when I have the time I don't have the energy and vice versa.  

jon - the fiber is to increase impact and stress resistance and add some damping. It does not reduce shrinkage. Concrete is Portland Cement based, which shrinks. Gypsum cements expand. USG Hydrostone is a combination of the two and can be admixed with acrylic, etc. plasticizers to increase damping at the expense of lowering resonance frequency. Paul added some plasticizer. I chose to run straight but added two different fibers which serves to suppress resonance & increase stiffness. I like grown solutions, and used hemp and rice awn fibers, but most folks would choose polypropylene or glass, etc. USG has zero, expansive and contractive products. I suggest you look there. I investigated air entrainment in the baffle core for lower mass & higher resonance frequency. These were follow-on developments after the CS5 cast marble baffle, which worked well, but cost and weighed a lot.

All, is anyone here bidding on that 3.5 EQ? If not, I'll try to snag it for the lab. (Remember the idea of fully balanced EQ with better caps and resistors?)

Wow Tom, you've been around!

I thought the bass on my Hales T5s was excellent, but thought the bass of the CD6 even better (more dense, focused, punchy) as well as the 3.7 and 2.7.