Thiel Owners

beetlemania -

Biwire is a special case. There are theoretical and empirical advantages. I've gotten good results with internally-biwired cable (in the same jacket). Problems arise with separate runs that the speaker designer can't control. An individual can evaluate including their own preferences. Also, there are upsides to single-wiring including avaialbility of all the conductive cross-section for big transients. Etc. etc. etc. Wire is a maze as well as amazing. Tom

Thiel Non-Model History – products that never were -

Prof – thank you for this question. Indeed we’ve covered a lot of Thiel history here over the years, but little about developments and decisions behind the curtain. This story would fill a memoir, which sadly, has not written itself. So, I’ll shine some light, while limiting the scope and depth for manageability. There’s always more.

Context -

Perhaps somewhat oddly, I’ll start at the end. I was informed by an insider that at the end Jim was working on an omnidirectional full-range driver. Such an omnidirectional driver would fit nicely into our global orientation of the speaker as mirror-image of the microphone and belief which we shared, that the omnidirectional mic captures sound most similarly to the ear, and far more faithfully than any directional counterpart. Although directionality in mics and speakers is a sad necessity in stage and professional arenas, the requirements can be more well managed in dedicated playback situations with less sonic degradation and higher retention of sonic information via room treatment and tuning while retaining  inherently superior omnidirectionality.

I can’t speak directly to that late idea-in-development. But I can recount early non-products based on first-hand knowledge of my brother and my twenty year lived history with Thiel Audio. What follows is a summary sketch of some of the experimental non-products during the early years of Thiel Audio.

Let’s venture back to 1974 at my Georgewown Road homestead. As a rung on our ladder to self-sufficiency, my Conceptions Design Studio had taken on Walter Kling as co-designer-craftsman, and secured early success in the high artisan-crafts marketplace. Our informal community sought a venture that would utilize and engage all the willing members beyond Walter and myself, in an enterprise with enough breadth, depth and horizons to support us for our forseeable future. This was the 1970s when autonomy and self-employment were hallmarks of the emergent counter-culture. We decided to fund Jim for a year to investigate whether his electronics knowledge could be responsibly applied to this task of right livelihood for a group of friends seeking meaningful co-employment.

Sidebar: At this time there were no computers outside large institutions, no internet, and only nascent knowledge of how loudspeakers really worked. The Thiele/Small Parameters were barely a decade old and not widely in use. Jim was inclined toward electronics with a first-interest in circuit innovation. More sophisticated amplification is where we first explored. Loudspeakers were seen as necessary tools to prove and improve amplifier advancements. Our survey of available loudspeakers revealed competing limitations and trade-offs, and no particular solution for accurate, revealing laboratory monitors.

Non-Product History -

In that first exploratory year we discussed, explored and studied what was needed for a really accurate and transparent research transducer. What floated to the top was a spherical globe around 1.5 feet diameter, fully covered with small (1/2” diameter) full-range dynamic drivers. More extended bass response could be achieved via greater sphere size and driver count, and/or by crossing over to a powered sub-woofer or folded horn. We built both a powered subwoofer as well as a 6’x 6’ folded horn to Jim’s specifications. The long story can be summarized to our realization that we were in over our heads with far more questions and considerations than our resources and scope would accommodate.

Lets count the most significant trials to date:

Non-product 1: Spherical multi-driver hung from a wire

Non-product 2: Powered subwoofer

Non-product 3: Folded horn subwoofer

All were built, tested, evaluated and set aside as exhibits for the Future Non-Museum.

Next stage was a distillation of contending technologies. It was clear that powering individual drivers with individual amps held extreme promise. Each amp could be tailored to the particular demands of each driver, and low-level, active crossover circuitry before the amp could produce better results at lower overall costs. The prototype that emerged was a tri-amplified three way, small format speaker with active crossovers including bass boost.

Sidebar: Note that Meridian had not yet come to market and to our knowledge there were no such products in the world. We determined that despite our collective enthusiasm for the concept, we as a self-funded fledgling enterprise could not support market penetration of such a product. To reduce further temptation, we burned the prototype on the pasture pyre.

Non-product 4: Self-powered speaker

Further distillation led us to what became the model 01, a 10”x 1.5” actively equalized, high sensitivity, full range speaker covering 25Hz to 18kHz. That product was fully developed along with its manufacturing engineering and feasibility studies. We began selling that product to local markets in 1975 with encouraging results.

By this time, our founding team included Jim, myself, my wife Kathy, Walter Kling and Fred Collopy with talents in business design-development, and emerging personal computing. I considered that team of 5 as essential for critical skills to take the plunge of full-time commitment to this business undertaking.

By request from users, Jim next developed the conventional 6.5”x 1” ported bookshelf model 02 to higher popularity than the model 01.

Our third market product was to be the model 03 a floor-standing 10” 3-way. Through its development we discovered that time-phase coherence was an important missing ingredient normally traded-off as not important enough for its trouble. We sidelined the conventional model 03.

Non-product 5: Conventional tower 3-way floorstanding model 03

We struggled for the next year and a half before deciding to accept the impossible challenge of producing a coherent speaker. The actualized model 03 with its sloped baffle time-aligning all the drivers, and first-order slopes maintaining phase alignment and impulse integrity was introduced in late 1978. It utilized the active bass equalization of the model 01 which persisted through the 03 conventional, 03 coherent, 03a, CS3 and CS3.5 (the fifth generation model 3, including the seminal non-coherent original version.)

The founding team survived only a few years, and the loss of Walter and Fred were nearly catastrophic to the business. I consider that upheaval as a fundamental loss.

Non-product 6: The fully functioning involvement of all 5 founders

As we gathered experience we learned to evaluate and accept/reject potential products in the hypothetical phase with minimal commitment and expense. That’s the highlights; let’s stop here for today.

Marqmike- PM sent

Massimo - The early 3.5 tweeter feed used a 6.5uF feed cap. It was tweaked in 1987 to 8uF, which is what you want. Only buy now if you need it. I will have a much better replacement soon.

The 3.5 mid and tweeter are front-burner projects. We are incorporating late-stage design elements into the 3.6 midrange platform - dual cone, advanced motor, to fit the CS3, 3.5 and 3.6. The 3.5 tweeter is obsolete and our replacement will also incorporate late-stage advancements to fit the CS2, 2.2, 3, 3.5, 3.6 and 5. Completion of midranges and tweeters is necessary to re-work the crossovers between them. For now, get your advice from Coherent Source Service.

The ScanSpeak 10F8424 is not robust enough; it will burn out. SS’s recommendation for drop-in is 12W/8524G00. CSS may have that driver or another of their choice.

Tom

Our plan is to have it available for a long, long while. There's plenty happening behind the curtain, but for now keep calling CSS as you have been for the past 7 years.

Prof - I know very little about this topic, only what was 'leaked' by an insider and not denied by another.

But, as I said, the approach harkens back to the very beginning, before we settled on dynamic drivers in an enclosure; and it attends to our shared first-principles of point-source, freely radiating energy without close range diffractive interference. And as I recall (from about 1974) our reasons for rejection were based less on technical appeal than on costs to market such a radical approach . . .

Sidebar: At our first 1977 CES, we twenty-somethings showed our model 01 and 02 and a static 03 prototype, and offered an unheard-of 10 year warranty - all to much interest. I remember being teased by an industry somebody that being from Kentucky, weren't we supposed to be barefoot and pregnant and sipping moonshine . . . ? Cognitive dissonance.  Imagine if we had showed up with seriously radical products beyond our active equalizer.

Since this is all water long under the bridge, I invite anyone to comment that might know more than I about this mythical omnidirectional project.

unsound - thanks for this input. It makes sense, including the context of return to a foundational idea before the company's launch - but with a life time of experience. Jim built every design on all the accumulated knowledge gained along the way. That product might have been truly awesome.

I routinely hear that the CS5 was Thiel's only cost-no-object offering. It was a niche-stretch at the time, but not cost-no-object. In fact Jim and Kathy chopped thousands of dollars at retail off the sell price due primarily to insufficient confidence of a price jump from under $2500 for the top of our line CS3.5 to what wanted to be a $15K CS5. They kept it under $10K by the loss of some product content plus damagingly thin margins, especially for a factory stretching its technical capacity. Jim emphatically stated that he would never design a speaker better than the CS5.

Anyhow, I'm pleased that he broke through that ceiling. And wish the world had it.

Thanks again.

Tom

ronkent - Regarding your mod. Be aware that the 3.7 mod that Rob suggested applies to only some speakers, not all. There was a QC problem with FST that required Thiel to test and characterize all incoming 3.7 coaxes and apply padding resistors as needed to bring the amplitude to standard. There were also harmonic distortion problems, which were failed and rebuilt in-house. When reworking drivers, CSS would add the resistors directly to the input terminals, or as in this case specify where to put them in the crossover.

Later, the coaxes were built to proper spec and noted with black trim rings. The 3.7 has an octave-to-octave balance within ± 0.5dB. So, you don’t want to pad it down unless it is out of spec, which is possible.

Note also that the mod as described here (padding both mid and tweeter) would effectively raise the woofer level a couple of dB. Moving the speaker closer to a boundary wall should accomplish the same thing. Also, any perceived brightness could be caused by harmonic distortion rather than simple excess amplitude. In that case padding down would reduce the gross amount of distorted output, but not cure the cause.

Roxy54 - for the record, with the 1987 CS3.5 we converted from 60/40 solder to silver solder for all our speakers. Our choice was the aerospace standard Alpha SAC-305 which is 96.5% tin, 3% silver, and 0.5% copper. It is not only permanent, but is technically superior. The improvements are audible. It requires higher melting temperature, but achievable with a 140 watt soldering gun.

spacebird - the number before the decimal point is the model. Higher is bigger. The number behind the decimal point is the iteration. Higher is more recent. More recent products incorporate all the learned advancements (that can be afforded).

Next up the ladder for you, if you have a larger room or want bigger bass or louder playback might be a CS2.2, 2.3,2.4. The 2.4 is a stellar sweet-spot.

I'm working on a product summery / timeline to help make the product journey clearer.

Welcome.

mchan888

Hello and welcome. This past summer I site recorded piano, bass, percussion and drums with my single-take, minimalist 2-mic documentary system, direct to SD at 32bit-192kHz. Earthworks QTC50s flat to 50kHz, no compression, eq, limiting, etc. Live to playback tweaking in the same space at the same time. We migrated from 3.6 monitors to 7.2s, my first up-close comparison of those models. I agree with your assessment. The 7.2 are the pinnacle of Jim’s work.

The 7.2 treble is not reticent. And its dispersion pattern is quite similar to the 3.6. So, if they sound dissimilar in your room, I suggest you lightly touch each tweeter while playing music to learn whether they’re both playing. If so, we’ll dig deeper. I have the schematics and welcome your PM to sort it out.

Andy2 and all -

I say that neither Jim nor Thiel Audio would espouse valuing ’"time coherence above other aspects of sound reproduction". Our company was built around addressing and honoring ALL aspects of sonic/signal/musical reproduction as a whole. Most designers - products minimize the importance of the time-phase aspects of fidelity, especially in the day that we did it. Only a handful of brands made time/phase behavior important - including Thiel, Vandersteen and Dunlavy and Quad, and possibly some smaller attempts.

Note our attention to time-phase was not above other aspects, but as one among several necessary ingredients for faithful representation of the musical signal.

Having paid attention to this stuff for half a century, my perspective is that keeping time-phase correct allows the ear-brain to pay attention to the playback signal as though it were real - thereby permitting a more holistic, immersive experience of the music. Although we rarely admit it, we humans do not possess unlimited brain-power. Work is required to reconstruct a musical signal that is missing its time domain content into an interpretation that makes sense. That effort subtracts from the state of consciousness that is possible when experiencing real music, either in its un-recorded state or its time-phase correct played back state.

Among the most frequent comments re Thiel/Van/Dun/Quad, etc. are ’naturalness’ and ’image density’. These are psychoacoustic attributes facilitated by the addition of phase-time correctness to the other realms of dynamic and tonal correctness.

I assess that designing for all of the musical aspects rather than discounting or fudging against the time-phase aspect requires an order of magnitude more effort. Everything becomes extremely more complex and difficult.

I can only afford a summary overview, the details took a career to address, and the work is still not finished.

Indeed.

Thiel's requirements of passing a square wave / exhibiting a single, proper step response, etc. increase difficulty so much that most practitioners consider it impractical or even a fool's errand. We went for it despite the difficulties. We were young and idealistic, plus we wanted to make a mark and improve the art. Over the years, we invented improvements that managed the inherent problems. 

The biggest problem/ limitation is dynamic range because each driver covers 7 octaves rather than 2 or 3. A driver acting outside its sweet spot has larger excursions, must dissipate more heat, enters break-up, etc. All those must be counter-acted with considerable difficulties. We began inventing new driver technologies withing the first several years.

It is also much harder to get smooth frequency response in a coherent system. Thiel's elaborate crossovers create complimentary circuits to correct driver anomalies that steeper slope filters would make less obvious. Also, we migrated to stiff diaphragms because their mis-behaviors are simpler, more predictable and therefore more manageable with circuitry. Those components introduce their own sonic degrades and add cost. 

We addressed these issues as cost effectively as possible. Our performance per cost was extremely high. As manufacturing director and later consultant to other manufacturers, I know that our output/cost was a multiple of average and our margins were a fraction of average. We tried harder.

Thiel's results were often less than best in some respects, but generally first-rate if one values over-all high performance on all fronts. Our speakers addressed everything quite thoroughly rather than a few things brilliantly. We believe our products supported a more musically authentic experience than conventional approaches.

I can say that Jim / we might not have gone there if we had known how hard it would be. I suspect that hind-sight and insight would have led us to the later-stage insight that we used in home theater products. We could maintain respectable phase coherence and proper time alignment while considerably reducing difficulty  with the fudge of keeping first order slopes for an octave on each side of the crosspoint and then migrating to second order symmetrical slopes beyond that. Out of band excursion and erratic behavior is greatly minimized while keeping the critical advantages of single step response and coincident time arrival. But you can't solve the puzzle until you know enough to solve it.

Most brands didn't and still don't even try what we we did. I'm glad we did.

Andy - you’re on it, and the CS5 is the best example of thoroughness competing with directness. There are multiple reasons for that ’reticence’. A big one that Atkinson and Archibald underestimated is amplification. The amps they used were current starved, delivering more anemic sound than best of form. The underlying root cause there is the excessively low impedance. I think Jim could have done better there - for another discussion. But to your point there are lots of components. My count from the schematic is 106 including 16 that are 1uF bypass caps. Note, we developed that 1uF (yellow) bypass with a European aerospace supplier as state of the art Styrene film x tin foil. Note also that Jim was fundamentally an electronic circuit guy. He worked as if the well executed electronic circuit did the job as well as could be done. That is debatable.

Of those 106 components, 32 of them are in the conventional signal path. Not particularly over-excessive for a 5-way design.

42 are in resonance (shaping shunted to common) circuits. Quite a lot.

And 32 are in analog bucket brigade time delay circuits in the  upper and lower midrange. This is a big deal where some history might shine some light.

We had gotten Japanese representation in the mid 80s which opened up the Asian market to us - quite rare for an upstart American company. Those importers pushed us for a ’statement’ product in a time where many such products were coming to market. Our best product was the CS3.5 at $ 2450/pair with EQ @ US retail. They wanted something at 10X that price, and we had 150 pairs pre-sold regardless of price. Jim was very cautious and less than wholly confident at that time that we could deliver high value in that class. In fact he didn’t want to make the leap and Kathy eased him into it over many months time. My (over-ridden) opinion was that this product-under-development had a ’natural’ retail price of $15K, but it was introduced at $9300. The other huge deal was time-line. The market wanted it now, and its natural development cycle was at least a year out. All that is to say there were significant stresses in the cycle, and stresses show in product strains.

Our signature straight-plane x tilted baffle format accommodated up to 3 driver set- backs by adjusting tilt and driver to driver distance. The CS5 had 6 drivers. It wanted a concave curved baffle for properly time-aligned driver to listener ear geometry. We solved the bass by placing the woofer between the two subwoofers (fore and aft the woofer launch plane) for a net single-point launch. The tweeter was time-aligned at the top of the stack. The upper and lower midrange had to be recessed about 5/8” and 1/2” respectively. The direct way to do that is geometrically. That would have required a thicker and more complex baffle, which could have all been accomplished with additional lead time, which the market wouldn’t grant. So Jim provided the electronic answer with analog delay, which he considered more elegant. This baffle fit our signature tilted flat plane. This long tale is to provide background behind how such products come to day.

I always pre-visualized new products as we developed our factory.  A CS5.2 could use a shallow cone upper midrange instead of the 2” dome to solve much of the timing issue, and applying our patent-pending double cones to the midrange drivers would increase basket depth options. The more complex 3D baffle shaping was feasible if Jim and Kathy could be swayed. I wanted to compete in the more expensive arena; whereas Jim and Kathy were not enthusiastic. Home Theater was rearing its head and Jim wanted foremost an arena to invent new products. HT became that arena.

So, Andy, back to your point that more complexity constrains a design. I agree. I also add that working to surpass such constraints is the business of innovation. We worked ahead of the curve, inventing many solutions that gradually became part of the industry playbook. The CS5.2 could have put many of those future innovations, such as motor shunts, rare-earth focusing magnets, formed double cones, etc. to good use. Such a path became reality with coincident / coax upper drivers, reflex bass (which I discouraged in our statement products) and so forth and so on. It’s a long tale of a complex stew with an outcome that the CS5 was never revisited, much to my disappointment.

But, as time went on and lessons were learned, there were never any more time-delay circuits, and metal drivers allowed simpler shaping filters; and the speakers worked toward greater clarity and dynamics – and reticence was reduced.

JA - awhile back you commented on the sonic improvements from the CS1.5 to 1.6 and larger improvement to the CS1.7. I would love to hear your particulars about the 1.7 and how it seems better to you.

I ask because the 1.7 is in a 1.6 enclosure. The chief differences are an additional bucking magnet on the tweeter, and the star-plane woofer. I hope to find a 1.7 to dissect, listen to and measure.

What is on my radar is to recreate Jim's CS1.7, which exists in prototype form. New Thiel modified the crossovers somewhat away from Jim's intent and I wonder what a Jim Thiel 1.7 would sound like. Gary Dayton says Jim's was better to his ear.

There's always something.

Tom

andy2 - Up and down is a weak point of minimum phase, multi-driver transducers. The coax is much better than discrete drivers, but coax to woofer geometry still comes into play. Right-left-depth is their strong suit. The up-down problem is exacerbated when the speaker’s aiming is marginal. You want its propagation axis pointing at your ear-plane such that you are at the center-sweet spot of its vertical propagation field.

The design axis assumes an ear position of 3’ off the floor and at least 2.5M - 8+’ away. You can mount a builder’s square, laser, etc. on the speaker at 36" up and parallel to the floor. Sight along that line. Adjust speaker tilt such that it sights to  your ear height.

Now it gets trickier. The effective set-back of the drivers changes relative to how much the speakers are toed in, which is dictated primarily by your room’s side walls. If the sight line points at your ear when the speaker is aimed directly at you, it will act lower if pointed more perpendicular to the front wall. (Visualize looking at the side of the speaker rather than the baffle. There will be zero driver setback in that case vs 6° (depending on your model) when looking at the baffle.

Explained another way, if you use setup software, the proper height and tilt is the one that produces the best square wave, step response, etc. at your listening position. That optimized geometry will put your ear at the mid-point of the vertical wave propagation arc. Your soundstage height will be at its best, as well as frequency response and everything else.

unsound - you or someone on this forum may have the reference where Jim suggested that arrangement. What I do remember is that his response was a reaction, not a serious suggestion.

I have tried that setup for on-site recording playback monitors with both the CS5i and CS7.2. Large rooms, placement problems, need for large sweet-spot, plenty of big amplification on site. I put a pair of CS2.2s behind the main out-facing speakers. Speakers were tight back to back, duct-taped to avoid buzzing. BiPolar (same polarity) won.

I liked the more powerful, room-filling deep bass with reduced eigenmodes.  There was also an increase in overall sense of spaciousness. But the 'sound' was less true to our remembered live-sound sources (in the same space, in the same session) as well as our headphone reference. In special circumstances it may have some appeal; but it requires deep pockets to implement. I would not recommend it for normal folks with pockets of typical Thiel users.

Hello Folks,

For those of you who don't know, Gary Dayton has bought CSS from Rob Gillum who has retired for family needs. The transition has been January through May.

Gary has made a formal announcement and provided more detail on the Thiel Audio Legacy facebook page being run by Micah Sheveloff, Thiel's long-time publicity and PR agent.

My re-involvement with Thiel Audio began in earnest as I learned of New Thiel’s impending bankruptcy. I encouraged Rob Gillum to buy the service department, and worked with him over the years to fill in my knowledge blanks and share what I am learning. My work has been to assess whether I could bring substantive improvements to Jim’s life-work as the basis for a follow-on enterprise. Over the past 5 years, we have explored and tested and co-developed with generous contributors and beta testers a wide variety of new solutions. Bottom line is that Jim was extraordinarily expert at what value engineers call ’balancing his designs’. There is no cost that doesn’t carry its weight. As duramax said: we are now in a different milieu. We Thiel owners already have our speakers and any upgrades can be bought without the cost burden of the retail store. We can up their game within reasonable cost parameters.

We have developed multiple upgrades, all settling around propagation organization, whether electrical, electromagnetic, fluid dynamic - whether inside components, wire or in the space between them; in the analog layouts and/or field management around components; these new solutions would not have existed, and/or been affordable in Classic Thiel’s time, within its framework of packing maximum performance into minimum price. We are reaching for a new cost/performance plateau.

One of the particular system limitations is the large capacitor banks that duramax mentions. Thiel controls its drivers over 7 octaves, necessitating notch filters at each driver’s fundamental resonance (or more) and first (or more) breakup modes. Common wisdom treats those circuits as functionary, without much sonic impact. Our trials say they contribute more sonic impact than given credit for. Our trials have been conducted on multiple models, but settled on the SCS4 due to its simplicity and shipability. They serve our team well. However, duramax has brought a focused interest at the top of the range, along with the listening room he built for sonic verification. Therefore, for these trials on capacitors to augment and/or replace the large electrolytic caps, we are running parallel trials on the SCS4 at my end and CS7.2 at his end.

To oxfordamps query: these prospective upgrades do not affect the frequency response. The speaker’s power balance remains the same, demonstrated by overlaying the curves. I should mention that in a Thiel design, any frequency range is affected by contributions from all drivers. You can’t merely change something in a particular circuit and expect a predicted result. That’s a major reason why most folks say true minimum phase / time aligned performance is (some form of) practically impossible. We can’t expect to improve on that core strength of Jim’s work. But, aural neurology doesn’t perceive only average power. It interprets elements such as increased clarity, definition. dynamic range and coherent alignment (quantum coherence). When those aspects get better, the area under consideration sounds more ’full, right, compelling, better’, even without factually being ’louder’. That’s what we’re working with: strengthening a weakness to bring that area into focus.

I’m not at liberty to explicate the particulars of how we’re doing what we’re doing, but I can tell you that 100% of the various levels of collaborators ’get it’. It’s not subtle, it is qualitative. Within weeks we should have results from various permutations on this particular (large cap) problem to give some meaningful observations.

Thank you.

Prof - Gary can handle all your needs. He was a rising star at Thiel and after resigning in the early New Thiel era he became Bryston's USA sales manager and then worldwide Marantz brand manager for Sound United. When that company became turbulent, he was convinced to pick up the reins as CSS, my first-choice outcome for our beloved brand.

When at Thiel Gary was the out-facing technical service rep / the other half of Rob's repair department. They worked together. Since this past January Rob and Gary have worked together to increase Gary's fluency with hands-on techniques. Rob will also remain on call as needed. No worries. Gary was also Jim's lab assistant and the lead man for the development of the CS2.7 after Jim's death as well as the CS1.7 with its next-generation RadialWave coax and StarPlane woofer. He knows his stuff.

To your question, all Thiel speakers can be serviced in the field. Some mechanics may not be obvious; but once exposed to the solution you will be able to do what's required. Again, no worries.

Correction - the CS1.7 is the CS1.6 next-generation tweeter (not coax.)

In the early years, Thiel considered reflex bass as a necessary cost-compromise only for entry level products ie home theater and models 1 and 2. When it came time to replace the CS3.5 with the 3.6, I resisted going to reflex bass in the 3, which had always embodied our highest aspirations. The equalizer needed improvements which were judged too expensive for the target price. Fair enough. I lobbied (unsuccessfully) for a modified CS5 style bass with overall system impedance high enough such that the falling bass impedance could stay above 4 ohms. The prevailing argument was that ports (a performance step down from our passive radiators) were ubiquitous, even in speakers selling in $6 figures.

Nonetheless, our foundational commitment to time-alignment was compromised. Reflex puts the deepest fundamentals a full cycle behind the action. As duramax has said " the bass player is out in the parking lot". Thiel’s reflex bass is implemented as well as I’ve seen at any price, but it does unavoidably delay the deep bass.

So you know, we have prototyped an equalizer using Jim’s excellent topology but adding regulation and more beef to the power supply,  higher grade caps and metal film resistors - while still remaining affordable.

Another problem with straight bass (non-reflex) is that very large driver excursions are required, which works against our underhung, low distortion motors. My assessment is that if push comes to shove, an overhung woofer motor is far better aligned with Thiel values than is the reflex timing error.

All of the upgrade technologies we are developing in the SCS4 workhorse will be applicable to all Real Thiel speakers. The 7.2s weak link is a 400uF bank of electrolytic caps in a parallel notch filter. Although considered less audible than series-feed circuitry, shunt filters are audible. I have developed two fixes. 4x100uF film caps, which is expensive and large enough to only apply to an outboard crossover. But another fix is to replace the 4 x 100uF electrolytics with 8x50uF higher grade Els in a bundled layout concentric around a new Golden Cascade 1uF bypass with its coaxial sections decreasing to 0.015uF. That’s the minimus value we landed on and used in the CS3, 3.5, 2, 1 and 1.2. The cost and footprint of this fix is accessible for an inboard crossover. Lovely improvement.

Regarding duramax’s silver cabling. I have also found silver to be magnificent and free of any excess brightness - depending on design - many elements are in play in cables. I have some custom silver plated copper wire that plugs right into my BiFlow topology. The extra cost of silver is significant, but my geometry has cost-effective manufacturability. So a silver option is on the radar. 

Our behind-the-scenes rate of progress has been called ’glacial’. It’s really slow, but also quite large.

Unsound - I agree with you. The equalizer does everything right sonically. The bass extension rolls off at the bottom at 12dB/ octave like real unamplified output. The upper frequency electronic ’tizz’ is solved with the new unit.

Our problem, especially in the early days, was under-pricing what we were delivering, and therefore living under very strict budget limitations. Note Dunlavy’s price multiple vs a similarly-reviewed Thiel. I did some cabinet consultation for Dunlavy. Behind their curtain, Thiel’s component quality and overall performance / cost and was far higher. The Audio Upgrades re-design of Jim’s EQ is significantly better, but would have come in at about double the cost of Jim’s design.

As you know, our plans include reintroduction of retro-fittable midrange and tweeter to remove the obsolete product concern, and then offer this new EQ as an upgrade for your upgraded model 3 equalized models. There were 10,000 pair of model 3s with that equalizer (combined 03a, CS3 and CS3.5). Quite a few of those are still in use.

As background, I advocated for a higher performance line of our speakers which would have allowed greater budgets. Think Lexus / Toyota. That idea didn’t fly primarily because they felt it would cheapen the perception of our stock products. Marketing would have been more dimensional, but I think we would have shone brightly in that arena. I would have preferred that business model vs diving into Home Theater for survival as value-priced 2 channel faded against emergent HT.

John - Jim worked hard in the CS1.6 to bring the sensitivity up. His spec was 90dB@2.83V. Stereophile’s review measured 94dB. So, amps far less powerful than for normal Thiels will work on the 1.6. The impedance runs just under 4 ohms across the board; that’s not as punishing as some other Thiels like the 3.6. Note howwever that the reflex slot is far more reactive than any other Thiel. Consult Stereophile’s review for details and considerations.

The binding posts with their big brass knobs are sonically destructive. Upgrade your sonic experience by backing the knobs all the way off and putting some locking bananas on your cables. When the time comes, there will be crossover upgrades for substantial improvement at reasonable cost. The 1.6 drivers and enclosure are better than its crossover component quality.

foamcutter - your best source of further information is Gary Dayton at Coherent Source Service.

The model 02 woofer had a rubber surround on a paper cone. It was made by GEFCO of Illinois.

Woofer: Gefco 4829 6.5” 6 ohm 1” aluminum former

Tweeter: Peerless KO 10DT 8 ohm

Second Thiel speaker released in autumn 1976 at $220 / pair

audiofilo123 - the 'funny' part about your Copland amp comment is that Thiel speakers require current-source power rather than the ubiquitous voltage sources. An amp that will drive a Thiel, including your little CS.5s, should double its 8 ohm power rating into 4 ohms and at least 1.5x its 4 ohm rating into 2 ohms. 

The Copland might do well with higher impedance speakers, but not have the current delivery capability that your Thiels require.

Frustrating? Maddening? Yes. Solvable? Yes.

Thanks for the instruction on the Copland. What do you suppose accounts for the Kinki Studio superiority with Thiels?

foamcutter - congratulations on your purchase.

The CS2.2 is dear to me, having served as my location recording monitor and small venue playback for 35 years. I have recently been developing performance upgrades, and the 2.2s have served as workhorses for much of that work. There will be user-installable performance enhancements available one of these days.

Note that Thiel developed this tweeter from the ground up for the CS5. Although its technology was later surpassed, it served brilliantly in the CS5, 3.6 and 2.2.

If you sent contact info, ‘gon may have scrubbed it. 

Gary has been converting/upgrading the CSS website. Try him again

Jon- stay tuned. I and my brother John also run CS1.2s. I experience a high frequency blackness that I will document through FF replacement therapy. I’ll post results here. 
Gary has FF and instructions.

Jon and other impatients- 

My hope is to join forces with CSS and other talent to re-incorporate Thiel Audio. I have a clear vision and a strong group of significant upgrade offerings. What I lack is critical mass to attract capital for the key ingredient. That is new drivers. Without that key ingredient, classic Thiel’s are dead men walking. I won’t itemize the disappointments, but I will say that my commitment continues.

First offerings will be ‘universal’ applicable beyond Thiel speakers. Cable and a family of suspension products plus a new capacitor family are in this group. Manufacturing start-up is the order of the day.

jafant - we do have a robust stable up upgrades that address issues beyond classic Thiel's scope. None of Jim's work is being altered. The jujitsu is attracting serious talent to form a viable company. 

I will no-doubt have relevant products for all of you. The big deal is to develop replacement drivers to keep these products (and more) viable into the future. 

Stirring the pot.

CS5s. The difference between the 5 and its 'improved' version is that Jim's newly developed woofers weren't ready when the 5 had to be released. The improved woofers incorporated copper shunt rings for more stable motor response. Those i woofers are not available (as far as I know). Nearly all 5s in the field are 5i conversions. The 'i' drivers have MDF mass plugs instead of the 5's rubber cone mats.

In  my recent minimal recordings I used CS7.2s as site monitors. Very nice. My studio has the CS5i, which are overall less articulate and nuanced, but their coherent bass alignment makes them more real to me. My invisioned CS5.2 will have a sculpted baffle for proper driver placement, thereby eliminating 32 elements for analog delay on the 2 midrange drivers.

tat - a geometric problem deserves a geometric solution. Since the CS5 baffle was cast, the complex curves only had to be created in the pattern. I was perplexed that Jim never went there.

TT

unsound - I have remembered that I also tried 'your' configuration in my Middle Crossing studio where we had a fairly large, well-proportioned, well tweaked room. I believe that duramax has two pair of CS5is, but I'm not aware that he has done this experiment. I had two pairs of CS2.2s, back to back and unitized, each channel driven by a stereo Classé DR9, one channel driving each speaker, with another identical amp driving the other two back to back speakers.

Side-step to Thiel's conceptual model - to have each channel act as much as possible like an omni-directional microphone. That causes extra trouble for set-up because the wide dispersion interacts more with the room than narrow dispersion designs. Adding the back-firing speaker exacerbates that set of problems.

On the other hand, the psycho-acoustics favor the 2-speaker arrangement since they are driving the room (as seen and aurally interpreted by the listener) more like real 3D instruments in that room, more like that mythical omni mic. This configuration will add more power to the sides and back than to the front-firing energy. So, more space and/or critical wall treatment will be needed.

My room was 16' wide x 24' long with porous-resistive walls that acted like a much larger room. In that room my standard spacing put 5' from the front (solid) wall to the tweeter plates. Since the back wall was porous, I could pull the speakers into the room without bounce problems from the back wall. I recall bringing them forward to around 9'. I lacked room to spread them wider than their 9' ctr to ctr. That tuning operation is a combination of physical experimentation and experientially gathered positioning data from decades of setup work. Tedium that pays dividends.

Regarding bi-wiring. I put considerable effort into that proposition due to its popularity in the field. I dislike it, like Jim disliked it. In Thiel's coherent milieu, some bonded point must be assumed as all the circuitry and drivers act as a unified system from top to bottom. The only point that we get full control of that unified system is with all drivers driven from a single point of entry. I also found that in the real world of cost-benefit, a 'better' set of cables provides more value than two 'lesser' sets. But even if you could get two identical 'better' sets, their working parameters would be different than those of the speaker as designed due to their considerably longer length and reflection parameters. My best results (half-century and counting) have been with single runs from a stereo channel (not bridged) through a single pair of speaker cables. By the way, in those trials my best bi-wire results were with internally bi-wire in the same cable rather than separate home runs between amp and speaker.

Phase-time coherent speakers like Dunlavy, Thiel and Vandersteen may present a best case scenario for this bi-polar proposition. Their radiation field is already propagating in phase and in time from top to bottom as though it were a single driver. Another fully integrated radiating field would form the other half of a spherical radiation field. You may know that Jim was contemplating a spherical solution when he died. Among our pre-Thiel Audio experiments, we all loved the spherical driver he made out of dozens of headphone drivers. But as green 20-somethings pursuing that idea was a bridge too far. 

Regarding Outriggers - Floor coupling is an important dimension for all speakers. Thiel’s outriggers broaden the base of support / footprint, with built-in adjustability for plumb and tilt. Their aesthetic matches later Thiel models nicely. Nice upgrade.

I have examined most of the market solutions in this arena, including the Gaias, and found room for improvement. A major problem, as unsound says, is that all flooring systems are not created equal  . . .  so one solution doesn’t fit all situations.

Thiel Renaissance has designed a family of interface products, which we call ’suspension systems’, in the form of sets of feet and a monitor stand that houses an outboard crossover. They create a  mechanical path rigid enough to keep the speaker anchored in space, while supplying an adjustable energy path to tune-out return-energy from the floor. The system is user-adjustable to match everything from bare concrete to carpet on wood, etc. There are 4 separate legs, in 3 sizes for small, medium and large speakers. Each leg anchors to a corner of the speaker base with its inboard end anchored to the speaker bottom to quiet its vibratory behavior. The outboard end accepts a threaded capsule (foot) with an interior bore for a reversible pin (toe) with a pointed or flat end. That toe rides on various washers and greases to tune the suspension to its unique work.

With so many balls in the air, it is unknown when we might bring this or other products to market. I feel no conflict with wisinskt’s proposal. Thiel outriggers are part of classic Thiel’s solutions that do their job well.

Stay tuned for news of Thiel Renaissance’s Speaker Suspensions.

Unsound - outboarding the XO produces significant improvement itself, plus it allows component orientation options independent of the field effects of the drivers, and larger capacitors. All good. Later Thiel speakers often had the XO in the bottom of the cabinet, which is a big improvement over placement directly behind the woofer, but doesn't address microphonic degrade from the vibratory environment or thermal management inside the sealed enclosure.

I have made and some of you have tested a stand-alone cube in placed behind the speaker. It works nicely, but raises issues of placement and cabling that disqualify it as a first-choice solution. The SCS series is a special case. It and all other stand mount monitors benefit from a stand that incorporates a suspension system and houses the crossover. That's the Renaissance Monitor Stand.

For floor-standers, we need a simpler solution that does the same things well. Our speakers target ear height is 3'. That standard is often hard to attain. I am allowing up to 1 meter target height, since down-tilt can accomplish the trig for proper signal integration. We have created an underslung crossover housing using that extra headroom. That cavity houses the XO in still air with ventilation potential, without the need for XO - enclosure umbilcals for each driver. All good.