Thiel Owners

How do I post a picture from my phone here?​​

Hi everyone.

I've been reading this thread for some time. I was encouraged to improve the performance of my beloved Thile C2.4.
I started working on XO and I thought about putting them externally. This is the preview of my work. 

Soon, I'll be doing some listening sessions

From Rob Gillum:

“The [Cs2.4] crossover can be accessed through the passive radiator opening. The base is not removable, as it is screwed, and glued. To access the crossover, you must remove the passive radiator screws and let the passive radiator drop into the cabinet. It can be rotated 90 degrees, and removed while servicing. To re-install the passive radiator, you can place your fingers at the surround, pressing outward to hold in place while re-installing the screws that hold bit in place.”

It is not glued but it is a bit of a puzzle to orient properly to get it out (and back in).

...

How hard can I push the radiator on the 2.4?

It seems to be a bit more than I've already applied and I don't want to push too hard ( I've the feeling it's glued tight..)

@tomthiel 

The pure by clarity caps is not being produced in 14 and 28uF.

I've sent an email asking if they would do custom made caps and will let you know if they do... 

On a somewhat sombre note.. I've managed to kill one of my coaxes (SCS3-N) 🤦🏻‍♂️

I really do hope Rob at coherent sound can either fix it (those units were 700 Euros a piece at the time) or fix me up with a new unit as he already has with the SCS's.. 

All the parts are ordered and/ or one the way, but this little accident is going to delay things a tad.. 

@beetlemania 

I'm not concerned with how big the capacitors will turn out to be, as I'm not going to stick them back in the cabinet. They will be fixed on a board, outside the speaker, with a bi-wire coming from the board into the 2.4: for this I'll need to put two more terminal posts at the back..

Cheers

Pieter

Imhififan,

For fun and a further learning experience you should try replacing what certainly appears to be steel fasteners holding your crossovers in place. I would do only 1 at first as my guess would be an imbalance left to right. Probably need to settle  in for 12 or more hours. If you do hear an imbalance or change in response then do the other speaker to match.

My preferred fastener is brass a non ferrous material.Steel will bend the intended field of flux.

I did this 20 uears ago replaciing steel fasteners with brass in and around the crossover of my Dunlavy SC4.. Then replace the cast resistors for Mills or Path for simple and quality upgrade. TomD.

jazzman - you should be fine. It seems most of the "difficult period" might have been 2003-2004. Thiel probably found better sources, plus China definitely improved its development and manufacturing chops year on year. 

The the tell-tale test is looking at your boards for the winding quality of the coils.

The pictured XO looks just like mine. If 2951-2 look like that, they're from the same era. Those black caps are polyester-mylar (one down from polypropylene), the coils are well-made from CDA-102 wire, which is high-end regulation wire, one step down from Thiel CDA-101, which is the best available. I tested these resistors and found them to be the non-inductive resistors that Jim had designed and made by ERSE. Although they look like normal sand-cast, but are better. Note that these PCBs are actually point to point layouts with no traces that can cause troubles. This wire has Thiel signature teflon insulation. All in, I would be happy with these boards, unlike some we have seen with obviously poorly wound coils and unknown insulation.

That said, if you're DIY-inclined, you could elevate the sonics by upgrading all resistors to Mills MRA-12s and all film caps to CSAs with the 100uF electrolytics to some upgrade recommended on this forum. I have eliminated all electrolytics and have developed an affordable CSA-type 100uF cap that works well. Not ready yet. 

I don't want to open Pandora's Box regarding product iterations and quality levels. I'm told that all 2.4s were assembled in Lexington, approved by Jim and tested to the historical standards. I have expressed my personal disappointment that some particulars of parts quality eroded after my watch. But, compared to competitive products in design and execution, I suspect Thiel stayed way up on the value charts.

Additional factoid: On my Thiel Warranty Registration, date of sale to original owner is listed as July 6, 2006.

@tomthiel

My Thiel CS 2.4s are serial# 2951 and 2952. Purchased pre-owned from Audio Consultants. Speakers were approximately 5 years old at time of puchase in April of 2011, with 5 years remaining on the warranty.  So presumably manufactured some time in 2006.  So with respect to the boards and parts, where does that leave me?

My CS2.4 serial number 384X, the last digit faded out unreadable, this is xover photo taken 5 years ago before modding.

About the CS2.4 serial numbers . . . I’ve been piecing together the history puzzle. What seems clear is that the transition to Asian inputs such as CS2.4 crossover manufacture was far from smooth or steady. Even though Rob says Lex 2.4 XO manufacture ceased around #220-230, that’s only part of the story. We have evidence from participants on this forum that later XOs were Lexington-built and that some later Asian XOs were decidedly inferior to some earlier ones. One key is that FST, the "best" supplier wasn’t the first supplier and that the road was pretty rocky to arriving at well-made units with top grade parts.

The Lexington XO department was not disabled until New Thiel moved to Nashville. While it was operational, runs of "old Thiel" crossovers could be and were made in Lexington with classic Thiel parts to fill in until acceptable units arrived from Asia.

With the records gone it seems the most reliable test is whether a board is built on masonite or not. If yes, then it is from Lexington with classic Thiel parts and QC - which means very tight performance assurance. If fiberglas, then more is unknown. Some Asian boards that I’ve seen are quite poor and some quite good.

Another potentially confusing element is the SE designation. The Signature Edition had a special cabinet with red Birdseye Maple veneer, SS bolts and outriggers, and larger, signed back plate. The only electronic upgrade was the ClarityCap SAs in the coax feed replacing the standard Solen caps. I think that run had its own serial numbers (1-300?) However many regular 2.4s have had the SE cap upgrade or better and some designated (red BE, etc.) SEs use Asian boards with SA caps. So, there are more variants of the 2.4 than might be assumed. I now have a pair on loan from a collaborator (#3729-30), in mature-Asian form with clean coils, polyester (MPT) caps and PP 1uF bypass caps, rather than classic polypropylene caps and tin-styrene bypasses. This is a de-spec iteration which I predict would sound inferior to a classic Thiel build. But it does sound delightful. Despite its somewhat shady history, what a wonderful product!

@pieper1973

The thought of putting Dueland caps into CS2.4 is wild to me. Even if Dueland makes the proper capacitance values (I don’t see anything close at Parts Connexion), the price would staggering. Multiples of the original price of the full speaker. But I would love to hear the outcome!

I suggest taking Tom Thiel’s advice, go with Clarity Cap CSA. Ideally, get full capacitance in single caps. 14 and 28 uF are tough to find but I would avoid going with 13+1 and 27+1 as in the original CS2.4. Running caps in parallel, I would go with something like 10+3.9+0.1 and 18+10. Try to get a more even balance among the two bigger paralleled caps. The 0.1 uF bypass is where you might go crazy and install a super-ultra bypass like a Dueland or Jupiter (even those are expensive!). You could add a 0.1 bypass to the 28 uF position as well.

Tom pointed out that the higher voltage models (eg, 630 V) have thicker film which is desirable, especially in the coax feeds. But I heard a difference even in the woofer shunts with 250 V version sounding more impactful than 100 V version of an otherwise identical cap. If your budget extends to Dueland$, definitely you can afford to replace the electrolytics in the coax shunts to film caps. Clarity Cap is a great choice for these, although be warned that their size is far greater than the electrolytics. That is, you might be challenge to fit everything within the passive radiator chamber.

Definitely upgrade the sandcast resistors to Mills MRAs or, if your pockets are Dueland-deep, maybe try Path or Dueland graphite resistors. Again, those ultra re$i$tors are hard to find in the proper values for the CS2.4.

To tomthiel and pieper1973.  We had discussed this some time ago, but a reminder that my CS2.4, bought from the original owner after one year, are SN 611 & 612, and have the entire Lexington masonite XOs and best parts of the era.  Seems unlikely they'd use Asian XOs at 250 and switch back to Lexington XOs at 600.  My 2.4s were nearly brand-new and certainly unmodded when I bought them.

Speaking of modded, I revisited what I had done around 2010.  I used 250V Clarity Cap ESAs, a 27uF, and a 10uF || 3uF.  For the 1uF bypasses I kept the existing Thiel bright yellow Elpacs in place.  And added the then-recommended Vishay MKP-1837 10nF bypass across both cap combos, improving the ESA sonics that smidge more.  The CSA versions were not yet available at that time AFAIK.

I'm not losing sleep over not using 630V, subbing in CSAs, or keeping the Elpacs instead of using a much-better 1uF bypass, but by now others have done more and may suggest improvements.  My guess is finally getting to Mills resistors would be a better use of my time.

ESA Sound: Similar in overall character to the Clarity Cap SA [used in the 2.4SE] but with more clarity and therefore a fraction more spatial. Like the SA they could still do with a bit more transparency but with a small capacitor placed parallel to the ESA this can be improved. The ESA also has a slightly warmish presentation and also benefits from making a total value using about 90% Clarity Cap ESA and about 10% Mundorf Supreme. This opens up the top end just nicely without altering anything else. Good overall qualities and an upgrade from the standard Clarity Cap SA.

CSA Sound: The tonal character of the Clarity Cap CSA has in common with all Clarity Cap capacitors that is well balanced and never fatiguing. The CSA shows a pleasent intimacy combining the clarity (pun intended) of the ESA with the smoothness of the larger MR. Relatively speaking, I actually found the step up in sound quality from the ESA to the CSA to be greater than from an MR to a CMR. Both the CSA and CMR use Clarity Cap's Copper Connect Technology but it seems to have a greater effect on the SA range than of the MR range. Maybe it's easier to improve lower down the scale than further up it, I don't know, but that is how it cames across to me. Anyway, in direct comparison to the CSA the ESA sounds a little rougher, the CSA seems to produce a more civilized image that is at the same time more neutral. "S" and "T" sounds that were first maybe a little bit rough around the edges with the ESA (I am being very nit-picky here) become free from grain with the CSA. I also found the CSA to mix extremely well with the Jantzen Audio Alumen Z-Cap. A mix of a minimum of 20% Alumen Z-Cap with the rest Clarity Cap CSA enhanced realism of space and lushness of tone. They blend together seamlessly. All in all the Clarity Cap CSA is a well balanced, neutral capacitor that is a welcome addition to capacitors in the lower price range.

@sdecker - wow also. I didn't know about the wayback machine!

pieper1973 Nice work. Your CS2.4 serial numbers @253-4 are right near the transition from Lexington-made original boards with American / European parts, point to point on masonite boards - to FST-supplied clones. If your boards are printed circuits, they're from Asia, but your parts may be original, which I consider higher quality. What I know from Rob is that somewhere around 220-230, production went to Asia, and parts sourcing gradually migrated toward Asian parts.

Regarding your cap question. I've corroborated Jim's migration to single caps rather than the 1uF bypass. A single value is superior when the cap is of very high quality, which you are proposing. FYI: Jim tested all the high end caps and chose ClarityCap. I did also, landing on the ClarityCap CSA, which is considerably superior to the original SA. CSA has (or will soon have) an improved version called Purity or Purity+ with thicker copper end caps and even better performance than CSA, at lower prices than your targets. You might put them on your radar. Keep us posted.

@jafant 

My serial number on the two 2.4's: 253

Music taste... About everything. As in writing this in listening to Mozart.

I bet much like Pink Floyd, Led Zeppelin, Joe Bonamassa, symphonies.. I'm not so much a liver of piano music, is rather hear violin, cello or oboe. Jazz.. older from Evans I really like (even if it is with quite a lot of piano).. 

My system at the moment had been thinned out, because I needed the money for the Atmos upgrade: the four SCS from Rob, all the components to build the XO's and the cabinets.. I also had to expand my amplifier section: I have the Arcam AVR 850 for a couple of years now for cinema and have recently bought the accompanying Arcam AVR P429 to power the SCS's..

I should my Omtec system (I'm not sure if this brand is known outside Germany, but over here they are very highly regarded under enthusiasts). I sold my two mono blocks, the pre-amp and the phono pre-amp (which is really loved and which I hadn't planned on selling.. somebody in eBay asked if somebody had one and I said yes.. which leaves me now on the search for a phono pre-amp; and there I have my eyes set on an amp which you have to build yourself, and is apparently very good. This comes down to the same thing as building your own speakers or at least upgrading the components where possible.. To be bought @ phelektronik.de.. 

So I'm not gonna be listening to my records for a while to come.

My record player is a Linn LP12 with an external lingo 4 power supply, Tiger paw sub Chassis, under plate Foundation and to plate Orpheus both from Vinyl Passion also replaced.. I have a Naim ARO with a Dynavector XX 2, MK.II.

Planned is a Creek Voyager i20. I used to have the destiny 2, before I sold that to buy the Arcam.. the Arcam does a great job of producing a lot of sound for home cinema ( I could have opted to buy a newer home theater system, but none in my price range have the sheer power which the Arcam produces.. and I need a monster to drive all these Thiels ☺️), but for good stereo reproduction or sucks. I need a dedicated amplifier for this.. hence the Creek... 

Further I have an Oppo 203, Arcam CDS27 SACD Player and Arcam rHead amplifier for my Sony mdr1000 and AKG K702 headphones and za Denon DCD-2500NE SACD Player.

@sdecker  

I've made four of these one point coherent speakers (nothing as fancy as in the pictures though) with the Thiel SCS3-N coax. Love m to bits.. 

@vair68robert 

"Moving the crossovers out of the speaker cabinet has interested me ever since I saw an Italian speaker for sale at Echo HiFi in Portland , this is was and is the only speaker that I've seen with external crossovers .  I'm still wondering why this isn't more common on higher end speakers , but me doing it is just beyond my ambition and capability ."

This is what I have done for the speakers I have already built and the others to come. I'm not even going to build the module for subwoofer into its cabinet and I'm definitely thinking about externalising the XO of the 2.4's.. but then I'll also have to remodel the terminal of the speakers.

I'm really looking forward to getting started : I'm waiting for all the parts, which are all in transit from USA/ UK and from Germany... 

Once I have all my parts I will keep you guys up to speed.. 

I'll be back.

Pieter

Wow @sdecker , great find!

   For years I've been lamenting that "New Thiel" seemed to have entirely thrown out all the info on "Real Thiel's" comprehensive website.  For me, that included the page of zilllions of links for every speaker made: technical supplements, reviews, owner manuals, marketing brochures, all the way back to the Model 01.  I don't know why I didn't do this years ago, nor have I seen anyone else on this forum bring it up.  I simply brought up archive.org ("the wayback machine") and looked for Thielaudio.com. 

Everything has been saved!  I just picked this one url and I can get to every pdf, paper, review (that's still on the web), even five open positions for hire.  There were many dates of different updates, but rather than crawl through the whole website history I'll offer up this link that seems to recreate the 4/12/2010 capture of the entire website.  Hope it works for the rest of you via this this.

https://web.archive.org/web/20100412030537/http://www.thielaudio.com/

  It's like finding out a long lost friend isn't dead after all...

pieper1973

Welcome! Good to see you here. Stand by until one of our DIY guys chimes in to address your query. The CS 2.4 loudspeaker is a Honey. Even better once upgraded to "SE" status. I look forward in reading more about your Musical taste and system.

What are the Serial Numbers (S/N) on your pair?

Happy Listening!

Hi..

Im new here, have posted some posts on another thread, but no one there..

I am the owner of a Thiel collection for home cinema..

I have two Thiels 2.4 which are going to be upgraded to SE, but I'm not quite sure on what for brand capacitor/ coils.. Miflex (kpcu) or Duelund..

But before it get around to them I'm going to replace the resistances on my four SCS3-N coax speakers with mills.

And I've just ordered four SCS coax units from Rob Gillum which makes a total of five.. I've just ordered resistances for all these speakers (mills) and the coils (in all my own built speakers I only have copper foil coils from Mundorf) and the center speaker will be fitted with clarity caps and the other four, for Dolby Atmos, with Mundorf.. 

And then there's the subwoofer... Thiel TSW 12.1.. 

I'll post some pictures when I'm done..

Just a question on the 2.4 upgrade to SE.. is it preferable to use a single capacitor with 14 and 28 uF (when I go for Duelund, I'll be ordering these values if that would be better..) or the combinations of 13+1 and 27+1, like it is now. And if I go for 14 instead of 13+1, would I have to change anything else (coils/ conductance or resistance values)?

Have a nice day

Pieter

@jchussey , I didn't realize that the original tweeters were also in short supply. I'm so sorry to read that you had such difficulties with "High Performance Stereo". Your reporting of it is a service to us all. I'm confident that your warning will be heeded. 

unsound - thank you as always for chiming in. Indeed a replacement driver is really the beginning of a redesign project and not the end. To elaborate: as you say, Jim considered all aspects as a system. Each driver has its Thiele/Small parameters carefully chosen for its tasks, plus its particular resonances and anomalies which he carefully modeled and corrected in the crossover such that the net acoustic roll-off was 6dB/octave with very flat impedance characteristics to realize very flat frequency, phase, time and impedance characteristics. Note that the only way he could get by with necessarily low impedances was by engineering an extremely resistive load. Changing a driver will change all or nearly all those parameters to defeat the subtleties of the design.

All that said, Madisound is a very knowledgeable distributor and they know a lot about their drivers. Rob has worked with them to choose the most appropriate available replacements.

Note also that Morel's inception was to pirate the Dynaudio designs, complete with international lawsuits, etc. So, the Morel replacements are quite likely the closest available replacement for the D28-AF.

Worth mentioning is the D28-AF was used in the CS2, CS3 and CS3.5. That 28mm driver has 20% more radiating area than 25mm domes.

As a generalization, I had hoped to endorse replacements by this time, but haven't gotten there yet. A real product update requires not only new drivers, but redesigned crossover networks. As a DIY, you can get pretty close with what's available, but a professional undertaking requires more diligence.

unsound

Rob Gillum recommended the Morels. I looked high and low for the Dynaudios and placed an order with High Performance Stereo, but ended up having to get PayPal involved because they took my money and never shipped and would not respond to my inquiries. I advise everyone here to be cautious dealing with them. 

tomthiel

I did in fact remove the 5.5" lag bolt and used a (perfect fit) 3" hole saw to remove the back of the cavity. The piece that came out was 1/2" deep. The Morel MDT32S are both in and I have the speakers playing for the first time in 20 years as I type. The fact that you were very likely the one who shaped the baffles on these in the early eighties is pretty special. 

Thank you for the recommendation on the bass equalizer repair. My uncle kept all of the documentation with these speakers and I see that the equalizer was repaired (at no charge!) on 3-8-93 for "popping and static noise on output". The RCA jacks were replaced with the CS3.5 gold type.

Jim

Tom D - the whole matter of bass is deep and sticky. I have spent considerable attention on the problem, and am still in the dark. But here are some thoughts. Put your boots on because we're going in over our heads.

At Thiel we did tons of (non-marketable) work on subs. There are so many issues  that we avoided the area until Home Theater required something. I think Jim's subwoofers deal with the issues extremely well. I have some now and agree with you that stereo subs are the way to go. There high enough frequencies for specifically directional cues. But of course its far more complicated than that.

Part of the problem is that there is no practical way (within budgets) to solve the bass phase issues which are so fundamental to Thiel designs above the deep bass. The (pre CS3.6) Model 3 family (plus the 01) had sealed enclosures which produce a perfectly damped low roll-off at 12dB/octave (second order) which mimics real acoustic instruments in real unrecorded spaces. Very satisfying bass. That bass roll-off introduces progressive phase shift that sounds natural because it is. Jim added active equalization to apply more amplifier power where needed in the bass without exceeding the power already required for clean midrange peaks.

However, when  a subwoofer (any subwoofer) is added there is an electronic crossover between the sub and the normal woofer, plus some unknown physical space offset injecting unknown time smear. Best case is a discontinuity that launches sub sound a full cycle behind woofer sound - albeit in-phase (I prefer "polarity") for augmentation. The ear-brain sorts out the temporal discontinuity, but not without consequences. What you do get is a pressurized environment (especially with stereo subs positioned closely) where the woofer "sees" a better physical impedance match between its force-motion and the air-space it is working into. Woofer distortion drops and articulation increases. 

Notice that on Jim's passive sub crossovers, you rarely actually hear the sub-bass. But it measures properly; it's there in the room. My fairly extensive auditioning and measurements corroborate his solution. Run the woofer full range for best placement and decay cues while using the sub just below audibility to create a better working environment for the woofer. The question arises as to how 'correct' the woofer signal is. In the retrospective work I am presently doing, and knowing intimately Jim's keen interest in 'the meaning of bass', I see Thiel's migration to reflex bass as a sell-out and know that it wasn't easy for him to accept. The transition from woofer to "port" (or passive radiator-same result) occurs at 4th order - 24dB/octave which puts the reflex fundamentals a full cycle behind the body of the bass coming from the woofer. Many folks (I'm one of them) hear that discontinuity as "slow bass" and less than natural, because it isn't. Reflex bass gets you an added octave (more of less) at extremely little cost, permitting overall system sensitivity to remain (twice) more efficient. Hard to side-step when nearly every peer does it even with speakers costing $6 figures.

Back to the question of how / why the laminar flow enhancements add so much sonic value - beyond understanding. Having spent the better part of the last couple years working on this problem I can offer some hints that may be gradually moving toward understandings. Let's examine some issues through the psycho-acoustic portal. We under-appreciate how much of what / how we hear is synthesized, including neural sub-circuits to enhance sonic recognition . . . we build models based on sonic inputs, not just from our ears, but also the mastoid process, and (lower than that) the solar plexus and skull and abdominal flexion and resonances. Saying that we don't hear below 20Hz is like saying we don't see outside some old-fashioned video frequency limits, or we don't smell unless we consciously identify what we're smelling. I know of weaponized sound at 3-6Hz, and euphoria-inducing sound at 7-12. Everything matters. Let's call it 'infrasonic' and pay attention.

Greg Lukens, the legendary inventor-audio engineer, evaluated an early version of DP's laminar flow technologies and hypothesized a sonic building-block explanation. The ear-brain builds its sonic conjectures (synthetic hearing) from the bass up. All harmonic structures are built on the foundation of the fundamentals. When those aren't there, the ear-brain "creates" them as phantom fundamentals. We don't know we're not hearing them. I posit that process of imagination to be quite benign. However, when we add that missing fundamental (as through a subwoofer) and that fundamental arrives at best a full cycle behind the upper harmonics and the upper harmonics of the subwoofer (or port, etc.) are a cycle behind the natural sonic structure coming from the woofer, we don't like it. We come to terms with it - we're quite excellent at accommodation - but nonetheless a lot of processing power is burned to get a less-than-satisfying hearing outcome.

We've gone pretty far here, mostly to address some of the difficulties of explaining a very complex subject. What I propose is that part of the reason we have such difficulty finding relevant measurements for the problems of "fake bass" or the bass-upper integration, or the unexplained imaging improvement, etc. is that these phenomena don't exist quite in the realm of the measurable. They exist in the realm of ideas and understanding, of epistemology - the study of how we know what we know, in this case what we hear. Let's posit (which I believe) that the surface-flow rectification contributes to fundamentally better organized leading-edge wavelaunch transients which produce substantially more lucid and interpretable fundamentals on which to build a harmonic stack that can be deconstructed into its component parts to sound like a musical event. Imagine that by removing significant chaos from those interacting onset transients, the auditory cortex can grasp the sonic event clearly whereas previously the event was dubious. A profoundly interesting aspect of my measurements is that "treated" laminar flow systems possess significantly better information from 0 to 20Hz than their untreated control system.  A very interesting aspect of all this is that we the listeners (controlled settings) do not necessarily attribute the sonic improvements to the bass, but more so call on qualitative observations such as "clarity, realness - accessible, involving, sweet, delicate, etc..  

So to your initial question regarding soundstage enhancement, I believe more brain power becomes available to deconstruct more spatial subtlety than when it was preoccupied with figuring out the basic harmonic structure of the sounds. Rather than technical measurements of the sound, we might come to greater understanding through brain activity monitoring.

That's all for now - For the Love of Music.

@jchussey , The Thiel's are a complete speaker "system". The baffle angle was determined by the depth of the specific drivers chosen at the time. The crossovers were designed to compensate for the specific driver anomalies used at the time. And, time is the operative word here, in that is the very thing that most separates Thiel's from the very vast majority of other loudspeakers; their almost unique ability to preserve accurate time. Any changes without further very specific modifications will undermine that quality.

While I was aware of the scarcity of genuine Thiel CS 3.5 midrange drivers, I was unaware that that extended to early CS 3 tweeters. Does Rob at Coherent Source have any? Perhaps @tomthiel can comment if something like this might be a suitable replacement:

Thiel CS2 Tweeter in original Thiel box Dynaudio D-28AF - Speakers (highperformancestereo.com)

and there's this:

THIEL CS3 ELECTRIC BASS EQUALIZER | eBay

These are listed as pickup only, but as this pair's woofers need replacement, I'd hate to see two pairs of these classic speakers ruined if one pair could be sacrificed to save the other pair. Perhaps the seller would consider parting out:

Thiel CS3 80s Real Wood | Dan's Shop | Reverb

Though there's something to be said about modifying these old classics to be improved, but I find it an anathema to see these old beauties bastardized Willy Nilly to undermine them to be compromised versions of what they once were.

Good luck with the project, I do hope you can save them.

Jim - Memory develops holes at 40 years out. This morning I pulled a tweeter on a CS3 I have in storage. Yep. The tweeter cavity has a 1/4" thick back with a lag bolt to the cabinet back. (No dodging - I did it!) That isolated the tweeter, plus was a quick-assembly method to clamp the baffle until the glue dried. And yes the bolt does add some structural stiffness for the tweeter mount.

But meanwhile, we learned about eddy-current distortions. On that front, that steel bolt is in line with the donut hole of the tweeter magnet which is the worst place for saturation distortion. I suggest that you'll get cleaner highs with the steel bolt gone. Best is no metal there at all (better than non-metallic which is better than what you have.)

That baffle is 2" thick. Deepening that pocket will remove the back, which is OK. The tweeter cup is sealed. I suggest adding some BluTac to the back of the tweeter cut to quiet any surface noise.

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

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.

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 

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

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.

I understand Tom Thiel has been working with surface treatment of a speaker baffle to enhance laminar flow while also reducing interfering energy. This energy migrates back and forth on a vibrating surface and causes a pile up of noise that does return back down the speaker cone colliding with the next wave launch. Everything vibrates and everything that does generates shear waves of many types. Shear waves travel in 2 or more directions and their collision create an infinite amount of more collisions.  These shear waves only travel in solids and all materials have a different shear velocity. The music we hear is the result of air affected by the shear generated in these solids. The air contacts the solid surface, so the air vibrates, and we hear those vibrations as sounds. Shear wave velocity passing thru any carpet will be changed by the material and the density. Hardwood and glass both have their own unique velocity. Look at your room materials and shape that is why they sound different. The compressive wave upon impact creates shear wave and those in turn travel and impact other solids and make more shear and compressive waves. And the beat goes on...This is a regenerative process. Because these vibrations generate sound you don't want to kill them all. It's tough to be selective without causing more harm than good. 

The early work of Jon Dahlquist and his use of spray materials. Spray flocking on the baffle and spray Nextel on the cabinet was the first surface treatment that ever made a profound impact on the sound of a speaker cabinet with no woof tones just more refinement and clarity. I know this impact as I heard the same cabinet untreated and then months later returned to me as treated.

Bud Purvine's patent on the Enabl process probably achieves much the same but applied directly to the driver surfaces His method launches away polarities of shear and Raleigh waves so they reduce collisions with the next wave launch..Bud now considers these waves as Rayleigh waves. 

standingwaves (positive-feedback.com)

Over the last year I implemented laminar flow devices I have built and placed in strategic front locations of my 27/21/9 ft room. I also have for years used now 3 Natural wool panels on the front wall 1 each at the side reflection points. The laminar devices are inexpensive to make and are the biggest acoustic improvement I have made over the last 49 years. They are a wow factor.  Small in stature they seem to comb bass frequencies making my dueling 12s enhance the mid frequencies. With placement the vocal clarity now coming out of the rear mounted ports is nearly as clear as what comes out of the front mounted drivers. They clarify the instrument location all along the watchtower. The sound stage is panoramic even more so when the active device is engaged. Pretty much the room boundaries and its contents are gone. Looking forward to seeing and hearing the Pauley and Thiel front baffle treatment..Tom D

tomthiel

Thank You for the history lesson on Model CS 2.4 and follow up to my query.

I am certain that 50 pair of Renaissance Monitors is highly achievable. Good to read that you are well and making progress. Have fun!

Happy Listening!

Happy Friday! All

tomthiel,

At some time there will be a stand-alone short run of perhaps 50 pair of this re-imagined monitor. No promises or projections as to when.

I'll be waiting, with interest!

Tom T & Tom D

Thank you for your guidance , now I don't have to agonize or worry about making a bad decision with inductor guage .

I had looked into the foil inductors after beetlemania's positive experience, but they are to large in diameter and they don't come in the smaller guages that are used on the Thiel crossovers .  

As for resistors , I already have about $100 worth of Mills mainly because of having to parallel resistors to achieve value and wattage .

Moving the crossovers out of the speaker cabinet has interested me ever since I saw an Italian speaker for sale at Echo HiFi in Portland , this is was and is the only speaker that I've seen with external crossovers .  I'm still wondering why this isn't more common on higher end speakers , but me doing it is just beyond my ambition and capability .

The simple and rewarding act of changing mounting screws has remotived me to start replacing componets on the crossover boards .  Rob

JCHussey- I would like to address your CS3s. This model is the de-facto watershed that put Thiel on a solid road to success. The CS3.5 gets more respect, but it is essentially the same speaker with a better midrange driver.

Taken together, the CS3/3.5 were designed before we adopted CNC machining, so more of the cabinet stiffness is in the walls with far fewer braces. The woofer and tweeter are the same and the cabinets have the same volume. Only the baffle angle is a little different due to different midrange acoustic centers and bringing the upper drivers closer together.

The CS3 & 3.5 are fraternal twins; any upgrades developed for those products will apply to both.

The sculpted baffle is a sharp point of Thiel history, and arguably responsible for Thiel’s survival. In the model 03a we had developed thick wool felt around the midrange and tweeter to attenuate diffraction. It worked well, was affordable; but looked less than elegant with the grilles removed. The curved baffle of the CS3 solved the problem elegantly but cost more. In 1982 we were a garage-shop operation. Our sell prices were cost-plus over an unrealistically low dirt-floor low overhead production cost. We needed to break out of me-too boxes to attract more sophisticated customers. My solution was to sculpt these 3-D baffles with ordinary shop tools, some ingenuity and lots of grunt. (We took an 8mm home movie of the process, which may emerge someday.) It goes like this.

Laminate MDF, route the driver mounts with templates, saw 3 x 45° facets with a progressive fixture on a tablesaw. Finish the conical roll-overs with a hand plane, rasp and sandpaper, then apply a wood-flour x drying oil slurry to fill the pores. I sculpted every baffle with one assistant.

One reason the CS3 put us on the map was timing. There was a deep recession in 1981-2 which killed many companies, and most of the survivors came to 1983 CES with re-warmed makeover products. We showed up with the CS3 that looked pretty high-tech / high-investment. It really got noticed.

From behind the curtain of time: Jim wasn’t convinced that "the market" would pay the price for that sculpted baffle. He co-developed an 03b using the same CS3 drivers, but with the 03a felt block diffraction-control baffle. Its introductory price would be $1150/pair @ 15% above the $990 03a. CES pre-show setup day response to the CS3 was so enthusiastic that the 03b never saw daylight. Jim, Kathy and I struggled till the wee hours to settle on the target price of $1850/pair, which J&K rolled back to $1750 at market production. We had broken out.

I consider the CS3/3.5 as the most lucid embodiment of Jim’s vision. This is the model I most want to recreate applying the technologies he continued to invent and refine through the rest of his career.

JAFant - what I meant to say is that the stock CS2.4 has its crossovers positioned quite optimally - more so than most Thiel models. Here's some background.

Although we were aware of sonic degradation when the free-form / bird's nest development crossover was compacted onto a board and mounted in the cabinet, Jim's approach was to cause the least damage while incurring the least expense.  In many models there is very little room between all those shelf braces, and the XOs got even more compact(ed).

By the time of the CS2.4 development in 2002, the cabinets had much less bracing. Not being there, I could only speculate about rationales, which I won't. But there is plenty of room in there to mount two separate XOs away from each other and from the drivers. I believe that geometry aids the 2.4's clarity and openness.

To your previous question about Renaissance offerings. What has developed is going way back to the 1976 model 02 - bookshelf / stand-mount monitor, mainly for pragmatics. They're cheap, simple and easy to ship. Mine have morphed from second order to first order / coherent source topology, being used as workhorses to compare passive parts, xo layouts, drivers and new technologies. Of special note is Doug Pauley's twin patented technologies that tame wave-launch turbulence. Progress is being made.

At some time there will be a stand-alone short run of perhaps 50 pair of this re-imagined monitor. No promises or projections as to when.

tomthiel

What can I say? Thank You,  for initial reports on the new-and-improved CS 2.4 by re-positioning the XO panel. This is the Model closest  to my Audiophile heart.

Keep up the excellent work!

Happy Listening!

vair68robert

Always good to see you here. I hope that your 2022 is off to a great start.

We have quite a DIY community here. Something for every Audiophile.

Happy Listening!

theaudiotweak

Thank You for sharing your DIY tips with the Panel. I am certain that tips help Tom in his endeavors.

Happy Listening!

68 Robert,

Thank you for your positive comments earlier today. I was so excited by what I heard today I forgot to answer you.... Tom D

jchussey

Good to see you here again. Nice score on those CS3 loudspeakers. Thank You for citing the Serial Numbers (S/N).  You could very well be the only Panel member that owns this Model.

What other gear is in your system?

Happy Listening!

I get it. Too bad Thiel XOs are so complex. But that's what it takes to control a driver over 7 octaves without having detrimental effects on frequency, phase and time response.

One of these days I'll find the opportunity to put a Path in the critical tweeter feed.

TT

The Mills are a great value at $5.00 but the Path are much better at $25.00.Maybe the Path's are not 5 times better but for me the difference is significant depending on how many are needed. The Paths are closer to the Vishay bridge builds. Tom

Tom - I admire your deep-end solutions. I bet they sound good!

For my part, finding cost-effective upgrades that fit the general (albeit stretched) value proposition of Thiel Audio has landed me on Mills 12 watt audio resistors, quite good for $5.

I agree about removing the XO from the enclosure. Not only is there head-banging, there's gradually rising ambient temperature and proximity to driver magnetic fields. The CS2.4 got the XOs pretty far from the drivers, but better is better. I have two forms of exterior mounting. Full-blown is a separate cabinet about 2' behind the speaker that facilitates air-flow and allows more space between circuits. The first-tier upgrade puts the XO on the back of the cabinet. With vibrational isolation tech, we get pretty far along that road. We also get airflow and spread opportunities. I'm pleased with the improvements over stock - especially when the music gets dense, loud or long - the presentation stays much cleaner and more relaxed.

I would not change the inductors but would change the resistors to the Path brand or with the Vishay nude resistors and build a bridge so you can reach a 5 to 10 watt power rating..Cost for the Vishay product would be over $100 per position. Other improvement would be to remove the crossover from the box so as to avoid the head banging it receives when internal. If mounted external then you have it at hand and can experiment at will. I have my boards mounted on 1.5 in. Audiopoints 1 in each corner away from the 2 inductors.Tom D

Hello to everyone on this forum. I have recently taken possession of a pair of CS3's that my late uncle purchased new 3/17/1984, serial numbers 0275 & 0276 and am in need of repair advice from this wonderfully knowledgeable group.

1) I am in the process of replacing the non-functional original Dynaudio  tweeters with Morel MDT 32S. The Morels are deeper by approximately 5mm so I need to remove material at the back of the cavity to accommodate. What is the best tool for the application?

2) The bass equalizer has a noisy (hissing, popping) right channel and I want to have it repaired. Does anyone have a recommendation other than the venerable Rob Gillum?  

Thank You,

Jim