Thiel Owners

JA - recovery was immediate, since re-entry does not say no. I wish I had more time with Rob, but our schedules only overlapped by a couple of hours. We're on firm ground with mutual goals. The trip also included other contacts and prospects. Getting away is good for perspective. Happy Holidays.

After been doing a bit research into "DSP option", it just happens that I may have found a mis-understanding, or may have been a false claim, with respect to time-coherent design.  I certain did make that myself in this thread.  

Apparently, I myself did say a few times in this thread that "time-coherent" design is only possible with first order filter.  But after doing some research into "DSP", it seems that a time-coherent design is possible for filter different type of filter, with different order such as 2nd, 3rd, or 4th and so on, NOT JUST with first order.

Now it's also a matter of definition as well.  If you want the strictest definition as possible, that is the only speaker that is qualified for "time-coherent" is first order filter then I guess there is nothing I can do about it, then if that is the definition, then only and only first order filter speaker can be called "time-coherent".

But my definition of "time-coherent" is a bit broader.  That is any speaker that have 0 phase shift and can perform a proper step response is qualified for "time-coherent" or "time-coincident".  If this is the case, then there are other classes of filter designs that are qualified as "time-coherent".

One example is "Bang and Olufsen" design, which uses LR2 (second order), that can perform a proper step response and has zero phase shift.  Here is a picture of it:  https://www.beoworld.org/prod_details.asp?pid=868

Not only that, but if you employ "DSP", then you can actually have higher order filter, which normally won't be able to achieve a proper step response, but you can introduce a "correction" factor in "DSP", that will make the overall speaker response to have 0 phase shift, proper step response and all.  

So now you can see that you have a situation where you have different types of speaker with different types of filtering topologies, 1st, 2nd, 3rd, 4th and so on, but all will have zero phase shift, proper step response, and and hence can be qualified as "time-coherent", which definitely will make things a bit complicated.  

So the question to ask is: is there any advantage of using "first order filter" at all?  Because we have seen that any filter order will be qualified for "time-coherent" and able to perform a proper step response.  Also another question to ask is: Are all "time-coherent" created equal?  Is one better than another?

By the way, has anyone had a chance to listen to the "B&O" MS150?
https://www.beoworld.org/prod_details.asp?pid=868

It is a time-coherent design, or at least that is the claim made by B&O. I think B&O uses the term "Uni Phase" design, or basically it means to have zero phase shift and able to perform a proper step response, just like Thiel speakers. But instead of using first order filter as the Thiel’s, it uses LR2, or second order filters.

pair of 2.4s at audio consultants until they close forever on 12/21.  They're listed at 1700 but I think the extra 25% off on the front page puts them at $1,275.  An obscene deal for what you're getting.  Makes me wish I needed more speakers.



http://audioconsultants.com/UsedEquipment.aspx

jon_5912

Nice catch!  Hope those CS 2.4s find a good home.

Happy Listening!