Thiel Owners

Tom - thanks for your comments. The entire arena fascinates me on multiple fronts. First is that "the problem" had been solved to our (Thiel's) satisfaction by 1983 with the CS3 contoured baffles that practically eliminated diffraction and baffle congestion. I didn't think a further problem existed.

My first hint was a demonstration that Doug Pauley did for a professional group (using a Tannoy speaker), that blew us away. We gathered further observational input from some leading audio industry luminaries, but the mechanics still remained mostly mysterious.

I pursued felt and flocking and Nextel, although I was unaware of Jon Dahlquist's explorations. Some of you beta-tested some of those solutions. They address the problem.

Then there was the CS3.6 thing that some of you reported where sometimes there was a screeching / pulsing / hashing, but no cause could be found. A couple months later I had narrowed down these so called 'sheer or propagation waves' on the baffle surface, primarily the flat area above the tweeter. 

The collaboration with Doug has applied his patented surface treatments for real advances toward mitigating a problem that had been unknown, unreported or otherwise invisible - but not inaudible.

BTW: you and I are on similar paths. I also ended up with genuine wool (F11) strategically placed on the walls. Also, there's a somewhat expensive addition via Ultrasuede - the real stuff - in the finest grade. US over F11 is where I was going before Doug came along and opened Pandora's Box. Thanks for the link and references.

All of this interference is nearly invisible and maybe at this point is not measurable but can certainly be seen in my mind's eye as myself and a friend have listened here and at his house. When I made my port treatment on my recent speaker rebuild, I couldn't believe the improved clarity of detail now coming out of the port everything improved. The tweaking of the bass frequencies was the catalyst, but what occurred was an enhancement of vocals and their placement.  So in search of a more specific solution, I may have found a solution to reduce some boundary interference which degenerates laminar flow. In a phone call about three years ago I mentioned my Dahlquist and Bud Purvine experience with you. Those 2 improvements I understand. The EnABL process by Bud Purvine took me a long time to figure out with the help of my geophysicist friend Debbie Miles. What I am doing now I cannot seem to measure but the improvements are pretty damn exciting. Tom D

tomthiel

Thank you very much for your response and wonderful history lesson on the CS3. I was 18 when my uncle purchased these and I learned most of what I know about jazz from him, and through the CS3's. Lovely memories.  

As I mentioned, the tweeter cavity is not deep enough for the Morel and I'm hoping for advice on the best method of modifying it. The long screw at the center of the cavity appears to be an important part of the structural integrity, so I imagine removing it and simply opening the cavity completely is not the best course. What would you advise? Also hoping for a couple suggestions on a repair technician for the bass equalizer.

Thanks again 

Jim - let's revisit your actual questions:

Tweeter cavity - I don't remember that tweeter mounting having a back in the cavity. It is possible that the early iterations, like yours, had it and it didn't stick or that you have an aftermarket tweak.

The first order of business is to make your tweeter fit, and if you lose that closed back, don't worry about it. If you keep it, a bolt  from there to the back would best be non-conductive and at least be non-magnetic. If yours is magnetic it may be causing more harm than good.

Onward to deepening the hole. Router bits are available with a flush-trim ball-bearing at the shaft end of the cutter. That bearing guides against the circumference of the mounting cavity and can be set to any depth. If you're not equipped, many woodworking shops would have such a setup.

Regarding repair of your EQ. I highly recommend Bill Thalmann of Music Technology in Springfield Virginia. He has the schematic and knowledge for repair. However, some parts are no longer available. We are working on an update. Meanwhile send me a PM to possibly trade yours for one I have here.

Tom Thiel with the recent improvements made to my sound system with my laminar devices it has even made the low bass more apparent as a supplement to the soundstage. This has been a noticeable factor to the landscape of soundstage for years with my stereo sub set up to my mains run full range. I understand some of the fundamentals of music start in the bass range but not all but the subs do have harmonics well above their crossover point.

I have never read a satifactory explanation of why a pair of well set up subs add to the enhacement of soundstage. Can you add your input and experience . Thanks.

Tom D