Thiel Owners

I'm still a Thiel owner (my entire HT is Thiel and my subwoofer is a Thiel SS2/Integrator), but my main speakers are as of last night Audio Physic Avanti 3. On a whim (well not so much as my buddy has a pair of AP Virgo 2's), I listened to them and was completely blown away. They do everything that I love about the Thiel's equally well, but added a smoothness and that famous AP ability to "disappear".

The only thing I really had to give was the Cherry color of the AP vs. the maple that makes my 2.4's look so stunning. Guess you can't have it all!

It's a shame to keep the 2.4's in storage (well, in a finished attic, so not much of a storage per se), so I will put them up for sale. If I had a second system, I would keep them, but I simply don't have the space for that (I've already claimed a room for my stereo and the basement for the HT, so I can't ask the wife for yet another space...)

After spending a few weeks with the CS2.4, I start to
notice a possible sound signature or if I am a bit
overly critical, a possible weakness given the design.
As with most Thiel speakers, the mid range driver is
smaller than the average mid of other manufacturers.
I was not part of the design process but I think the
main reason for using small mid driver has to do with
time-phase coherent.
We Americans have a say "There is no substitute for
cubic in." In speaker design, I guess the equivalent
would be "There is no substitute for membrane area."

When a small mid driver is used, one has to cross
over to the bass at a rather high frequency so the
bass driver can help out the mid when playing loud.
In the case of the CS2.4, I believe I've read that
the cross over freq. to the bass is around 1KHz.
But still ultimately the laws of physics come into
play and being a small mid the advantage is faster
transient speed and better clarity which is the
hall mark of the CS2.4. On the down side though,
at high volume, the sound can be a bit strained as
the mid does not have enough membrane area to pressure
the air at low frequencies.

With the CS2.4, especially with saxophone, the "blah"
produced lacks a bit of weight and at high volume,
the depends on the recording, the vocal can sound
a bit shrill especially if your electronics are sort
of in that direction. When you hear people complain about
the sound of Thiel speakers in general, I think this
is what they talk about. If you're used to speakers
which use larger mid driver (for example the Wilson
uses 6in and even 7in mid) that have a more relax and
warm mid range, you probably think the Thiel house
sound a bit on the bright side.

Anyway, I guess you cannot have it all. surprised :-)

Pretty much all designs have trade-offs. You can reduce, if not eliminate, them by throwing more money at it but real-world speaker design is a series of compromises. Sure, Wilsons can play loud as hell, but at what (sonic) cost?

The smaller midrange diaphragms in Thiels are much more rigid than those used in Wilsons. This is a function of both materials and size. The upside of Jim Thiel’s choice is that you hear far less distortion. IOW, a more realistic recreation of the recording, warts and all.

Other than the TAD Ref One with it’s largish coax (beryllium at that), all of my favorite speakers have midrange drivers <5” diameter. Tbf, ability to reproduce The Who at concert SPLs is very low on my list.

My ATC 110s have a 3" midrange that will play incredibly loudly.  it's the same midrange that is in the SCM 300 ASL that will do 121 db continuously.  I doubt any Wilson product can touch that.  The crossover to the woofer is 380hz.  The midrange also has extremely low distortion.  

I decided I liked small midranges a while ago and I think the main reason is that they don't beam.  That means the off axis response is much closer to the on axis response.  Reflected sound will not be radically different from what comes directly from the drivers.  This means the speaker will sound good in a variety of rooms.  This is one of the first things I noticed about my Thiel 2 2s.  I got them for a living room system that was far from acoustically ideal and they were great.  The first order crossover means that if you walk right up to them they have wild response fluctuations due to the driver interactions but the overall sound in the room was immensely enjoyable.  Sit back in a good spot and get a great audiophile experience.  Turn them on while you're doing other things around the house and get a great casual listening experience.  

http://atcloudspeakers.co.uk/hi-fi/loudspeakers/tower-series/scm300aslt/

http://studio-hifi.com/images/ATC75-150S_JeffBagby.pdf
"As you can see the nonlinear distortion is extremely low, with 3rd order in the neighborhood of -70dB at my low crossover point. These levels are very close to the noise floor in my room and I would consider this to be in the state-of-the-art range for midrange distortion. "

jon - those ATC measurements are commendable and likely to produce very fine results in the frequency domain. For this Thiel thread, I will add a few comments.

Loudness: 4th order or any higher than 1st order slopes allow the driver to operate in its robust range and attenuate the out of band requirements, so they can play louder cleaner. Things get so much easier in that world; that's why most designers go there. Thiel's 01 used 3rd order and the model 02 used 2nd order slopes. The change for the 03 and after to first order increased the difficulty of the design undertaking by an order of magnitude, at least.

And as I have mentioned in the past, by removing phase and time coherence, the ear-brain gives a free pass to many other anomalies; they no longer are scrutinized as real and therefore can be ignored. Examples include the edge diffraction and soft-dome break-up modes. Diffraction isn't particularly audible with high order slopes because the brain doesn't associate the source with reality, and diaphragm breakup is attenuated to lower loudness and becomes less audible. Note that the literature considers 4th order Linkwitz-Reily filters to have 0 phase shift, but that is because they pretend that 360°, which rotates phase angle a full cycle, is exempt because 360° looks like 0 on a graph. Also, the speakers described do not look time-aligned, so the transient wave-fronts will reach the ear at different times as well as phase delayed relative to the input. Many commentators say that doesn't matter, which is because the ear-brain is so good at reconstructing the probable intended sound which has been scrambled by the speakers. Our work at Thiel demonstrated to our satisfaction how that brain-work of reconstructing the probable-intentioned waveform serves to decouple the listener from the emotional experience of the music. As I have said, most commentators disagree and deem higher order filters to be OK, and first order, phase coherent wavefronts to be unhearable and meaningless.

I suspect that Thiel lovers have identified the "trueness" of phase and time coherence and are willing to put  up with the attendant compromises including less smooth frequency domain performance and higher audibility of many ancillary anomalies. Jim spent a lifetime identifying and reducing those anomalies (sonic baggage) and I am now stretching the envelope to include cleaner electronic performance which original budgets and materials science did not permit.