Thiel Owners

I have to eventually ask Tom if all Thiel products are optimized for far field?  That is if I measure the frequency response at far field then repeat at near field, should it deviate a lot?  At far field, room interactions may hide things that near field will reveal.

I have seen some step responses measured by Stereophile for some of the Vandersteen speakers and John Atkinson has to move the microphone up and down to get it right otherwise the treble response will peak too much (probably due to deviation in phases).  But I think it's like cheating.  The listener probably will probably not know which way to move to get the best step response.  Also it seems like Vandersteens may sacrifice the freq. response too much in order to achieve time phase coherent.  For example, the tweeter crosses over the mid at 1KHz which think is pretty low for a tweeter and I wouldn't personally do that just to get time phase coherent.  At least I don't think Thiel speakers do that. 

I think when you measure at far field such as 8ft, the drivers will in general integrate better because the phase a better aligned at far field vs at near field.  For example, if you place a microphone at 1meter at the midrange height, the acoustic distance from the mid to the tweeter will be, let say 4in.  Now if you move the microphone at 8ft distant, the relative acoustic difference will be less than 4in.  It's like looking at things from far distant and your movement will probably not change the field of vision very much vs. if you're really close.  

With the wealth of knowledge, experience and appreciation of the experience of music on this site, especially Unsound, of course Tom Thiel and many others, I am well on my way to an upgraded system with the relatively recent addition of 3.5s to my 2.2s. For serious listening beginning last month I can now alternate them on my new vintage B & K m200s with 400w/4 ohms, but still need to use my old integrated (80w/4 ohms) as a pre for now.

They are in different similarly sized rooms with different orientations, each opening to another room and likely a 2 or 4 AWG discrepancy in speaker cables and several feet of length per pair, so any comparisons between the 2 must only be taken as preliminary observations. The additional power really made the 2.2s shine in every way possible, not news to (almost) everyone on this site. My long held view that they were a very slight bit bass shy unless played loud was completely wrong, absolutely present for the mid bass with the 400w, somewhat more than the 3.5s even, but not quite as well defined. What was missing was the sub bass that one feels with the 3.5s. Outside of the higher frequencies, the 3.5s have a bit more of almost everything, especially soundstage and depth, and are easier to drive.

Love them both, they are more alike than not, and could never part with either because each gives a slightly different experience of the music, but I do listen to the 3.5s more. With their present configurations one could almost make the overgeneralization that the 3.5s lean a slight bit more to the analytical side while the 2.2s to the more impressionistic, but that would likely be modified and refined if all other things were equal.

As many others have said, each step up unfolds new insights and enjoyment. Funny how the more I learn the less I know, but I am enjoying the process tremendously.

Beetle - Stereophile's next publisher after Larry Archibald did not tolerate the editor producing content that put their major advertisers in dim light.
Andy - Design intent is 8' minimum distance. Farther away yields larger listening window.
Jon - power response is the energy dispersed through the whole room, which affects overall tonal balance, especially with phase coherent systems where reflected energy begins at the speaker as coherent waveforms.
Robert - I like the tenor of your observations. Keep it up.

As you all know, I am taking on the 3.5 after the 1.5. Both models are from the golden era and both sold more units to more loyal customers than any other products (the CS2 also fits that description, but its actualized design limitations and lack of parts takes it out.) My 1.5s are on their way. I'm looking for a pair of 3.5s to borrow or buy.

Tomthiel, PM sent.

Ok, let's try to keep the concepts clear. Time coherence is different from phase coherence and obtained differently. Thiel speakers are time coherent from an 8' distance as the drivers are set back in the baffle and the sound needs to travel some distance to fully integrate. In my measurements, I obtained time coherence within a few mm. at 8 ft among the drivers excluding room reflections by using freq dependent windowing.
Phase coherence in Thiel speakers is at best minimum phase, which means there is a phase shift that is measurable. The first order xo filters and the drivers have a minimum phase effect. This minimum phase effect can be reduced with dsp and other cancellation methods and linear phase can be approached above 100 hz. As Tom has warned, the preringing can become an audible problem so pick your imperfection.
Andy, if your point is that all speakers have some phase shift dependent on the frequency, there is argument. Thiel specifies it to be within 14 degrees which is considerably better then most alternatives. With dsp, the phase shift can be further improved if desired at the expense of potential preringing, although this effect can be mitigated to some degree with additional filters.