Good work. I should comment that lowering the RF in itself hurts things. However, it is likely that you also decreased the resonances for net gain in quieting the cabinet.
Thiel Owners
Guys-
I just scored a sweet pair of CS 2.4SE loudspeakers. Anyone else currently or previously owned this model?
Owners of the CS 2.4 or CS 2.7 are free to chime in as well. Thiel are excellent w/ both tubed or solid-state gear!
Keep me posted & Happy Listening!
I just scored a sweet pair of CS 2.4SE loudspeakers. Anyone else currently or previously owned this model?
Owners of the CS 2.4 or CS 2.7 are free to chime in as well. Thiel are excellent w/ both tubed or solid-state gear!
Keep me posted & Happy Listening!
13,529 responses Add your response
I got good result tweaking my loudspeaker (Diapason Adamantes MKI in my second system) enclosure taping the inner with thick lead plates (two millimeters) coupled with polymer glue in order to get a sort of sandwich that allow to lower the resonance frequency, actually it works well, the bass extension, focus and and solidity is audibly improved. |
I don't think one has to forgo classic Thiel virtues to attract the HT crowd. The concentric drivers lend themselves to it.The more recent models might be adapted to the more recent HT formats. Imagine another concentric driver mounted on top of the 3.7's dome? Some of the most expensive budgets spent on sound is by Hollywood. I believe one of the reasons HT hasn't attracted that many audiophiles ( expense aside) is the fact that most of them realize that properly placing two channels is challenging enough adding another 3 to 5 or more is daunting, if not impossible. I've touched upon this before, but let me bring it up again. If like Thiel the objective is to get everything off the recording as accurately as possible to the listener, no matter how much attention is paid to the system chain the room itself will ultimately impose the biggest hurdles. One way to help ameliorate the problem is with DSP. I suspect that one of the problems with using DSP in the past is that direct sound from the loudspeaker to the listener and the reflected sound from the loudspeaker to the room to the listener has been convoluted. While is it has been estimated that 80% of the sound one typically hears is room reflected (and therefore corrupted), we know that given sufficient time delay (estimates vary from about 5-8 milliseconds, which loudspeakers placed well away from the walls will provide) listeners ear/brains will prioritize the initial direct sound from the loudspeakers over that of the reverberated room influenced sound. That might(?) be fine for symmetrically placed two channel systems, but such symmetry might well be impossible in typical listening environments for multi-channel (and perhaps preferably so for other reasons) but what was once not much filtering/processing on the ear brain has now become greater in amount and more complex from varying room influences. The problem with DSP in typical room set up is that when correcting for the secondary distorted room influence, one ends up correcting the primary direct sound from loudspeaker sound as well. That can become quite unnatural to the listener and especially more so to those listeners not in the sweet spot! Keep in mind that many recordings already have their original room influence on the recording, now with typical loudspeaker setup we're adding/superimposing more. That might be best be described as distortion. And with HT/multichannel setups distortions that varies from channel position. That's a lot of ear/brain filtering/processing, which might become fatiguing. One way to offset this myriad of convolutions is to minimize them. If the loudspeakers baffle is very close to room walls, then direct sound and reflected sound become more of one, and then the DSP room corrected sound and the reflected sound become more of one and the same, with no or little imperceptible timing issues. The advantages of such loudspeaker placement becomes more evident in multichannel and HT, especially so now that flat screen monitors/screens are fairly standard with their lack (or close to it) of projecting boxes that previously added side reflections. Placing five to seven channels 3-5 feet will into the listening room with 16-20 feet across from themselves (which would provide 8-10 feet from loudspeaker to listener) would require huge rooms (and perhaps a bevy of potential tripping speaker cables) not readily available to the typical consumers. Obviously having the loudspeakers close to the room walls could have decorating advantages that can't be undervalued in the marketplace. With such wall placement, perhaps less labor and money(!) might be placed on cabinet beauty. The downside might be an increase in baffle area to compensate for box volume losses. I have some ideas for such a baffle box, but I've probably taken up to much space already. Still, I suspect that such box reduction costs might be somewhat passed on to the consumer for ultimate multichannel affordability and commercial competitiveness. On some level Thiel has been doing just this for years and with great advantage with their concentric drivers(!), think Powerpoint, Dewdrop, etc.., just without the DSP possibilities.
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Regarding theater: I know a universe where the audio dimension of theater adds a profoundly deeper and more complete involvement to the video. As coherence enters that total immersion world, serious magic happens. (Little known factoid: Thiel worked with IMAX and Skywalker Ranch with hugely promising potential. But, Thiel was not a collaborator in that league. My daughter Dawn grew up inside the company. After Jim's death she said "Thiel Audio wasn't a real company, it existed so that Jim could design speakers and have a life." (Same girl who defined the 'leaf effect'.) Bottom line: Coherence is huge in theater playback and Thiel has technologies and know-how to take that niche over the top. George Lucas et al spend untold resources keeping every ounce of phase/time relationship intact through triple digit track counts and processing paths. I vote that we shortchange ourselves by saying it's OK to scramble it at the end. Now, imagine the CS4 (ever notice it's absence?) |
Great ideas, guys. jon - I highly recommend checking out USG Hydrostone instead of concrete, for reasons I've previously enumerated. rule - someone has to pick up the ball, I'll do my part. andy - good ideas. I suggest that Thiel's present driver technologies are world-class and viable. The likely buyers for those patents are FST, Thiel's Chinese supplier and Meiloon, New Thiel's Taiwanese supplier. Whoever buys those patents would have a big jump on the kinds of products you envision. I would add pro-audio to the mix. Create the music with Thiel monitors. By the way 24bit x 192kHz digital is now feasible and wow does it work. Also, active crossovers are readily executable in analog for the purist products. A visionary partnering company capable of producing the controlled amps is key. New Thiel also developed some seminal digital technologies. For the right buyer, the Thiel intellectual property is likely to be a huge bargain. |
I think having products for home theater and also some very expensive, high margin products is a good idea. Home theater especially should be active and the crossovers should be digital. that would allow for user selectable crossover slopes which would be cool. You want to watch an action movie, select 4th order and crank it up. For drama you bump it down to 1st order for maximum realism. There would need to be preprogrammed EQ overlays of the crossover to handle driver response imperfections. Keep the traditional Thiel line for people who prefer analog or who already have electronics and just need speakers. I definitely agree that there were some directions the company could've been taken that would have had a far greater chance of success than trying to charge 6k for 3k worth of PSB speakers. I think I'm ready to dive in and attempt to build a speaker box for a kit. I'm planning on buying the Zaph|Audio SR71 kit from Madisound. What I want to try is make the back and sides out of strips of 3/4" mdf. They will stack on top of each other in the corners, leaving horizontal 3/4" gaps along the flat parts of the box. I'll drill holes in the corners through all of the boards and run 1/4" threaded rod to hold them in place. The sides and back will connect with an effective hinge at this point so I can lay the whole thing out flat and pour concrete in the gaps. That will result in the walls being half concrete and half mdf. I'll hold it together by tightening bolts to the threaded rod running through the corners and also through the sides in places. It's hard to explain and I can't find an illustrative picture. Ultimately I hope to have no wall flex typical of mdf, minimal high frequency ringing from the concrete, reasonable weight, and low materials cost. This is my first try so we'll see how I do. |
Anyway, in a parallel universe where Thiel still exists with the sound that we have come to love. But what if just for fun ... I would partition Thiel into three distinct product lines that can leverage the driver technology from the time-coherent designs. There needs to be a Thiel house sound which is based on its magnesium/aluminum concentric drivers so people know what to expect. I assume the cost of designing the drivers is pretty high so it makes sense to spread the cost to more product line. Also having more products will improve growth and revenue. Here is how I would position three product lines that buyers can easily identify with. 1. Home Theater 2. Luxury 3. Time - Coherent For Home Theater, sound quality is not as critical so first order is not needed. This will shorten the design cycle but still use some variance of Thiel magnesium/aluminum or even existing drivers but matching drivers are not as critical due to the use of high order (which also should lower cost). The product will include a two way, three way, four way with the fourth being a self power subwoofer with some type of room correction. The styling language will be similar to that of the time-coherent product line. The sound should have the same musical clarity that is known of Thiel. You can use 2nd 12db roll off which is not bad. It has the clarity of the higher order filter but can retain most of the musicality of the first order design. For Luxury, this is where Thiel can lavishly throw everything at it. The price will be in the 30 - 50K range. It does not have to have first order so that you can have a freedom of selecting different driver configuration. Think of this as Thiel own version of Dynaudio Confidence. You can have two midrange drivers, multiple bass drivers. I can think of having the concentric driver cross over at around 1000hz to a pair of midrange then cross over at around 200hz to a pair of bass drivers. Higher order can be employed. The drivers and styling should have some unity with the time-coherent product line. This is where Thiel can showcase its aristocratic side for the rich. I think this is where the new Thiel was trying to do but the problem is they abandoned all previous Thiel signature thus having absolutely no brand recognition. This would only work if you can tie in with the rest of Thiel products. Not only it will save cost from sharing the drivers and styling, but buyers will recognize them as Thiel products. And last but not least, the Time-Coherent will remain the same as before, but it will also serve as a corner stone for other product lines in term of designing the driver and developing a styling language. |
Your confusion may come from the SE availability. Years ago, Jim developed a Signature Edition for the CS2.4. Most of the upgrades were cabinet related, but there was and is a crossover upgrade which replaces the 2 feed caps (bypassed with styrenes) with 2 ClarityCap SAs, unbypassed. SAs were best of form at the time. The sonic improvement is noticeable. Some folks buy those caps from Rob. Our upgrades are considerably more extensive and expensive and not yet finalized. |
Note that any replacement driver would necessitate crossover changes since all parameters affect the various resonances which are compensated and corrected in the XO. Also, that driver had some level of Thiel proprietary magnet geometry and so forth; that motor came after we were developing sophistication beyond normal
industry offerings. So, let's try to keep the motor and find or create a replacement coil system. Motors are forever. Cone systems with their surrounds and spiders are for pretty long term precluding damage. It's the voice coil and lead braids which burn out or fatigue. It is possible that we could source that voice coil, on its former or not, and devise a replacement protocol, essentially rebuilding the driver using its own motor and cone system. What d'ya think? |
rule - I would need some prompts to address the lack of braces. The 3.5 development dates from around 1987 - I am unclear exactly when. That's after our first CNC which is when the pierced shelf braces became feasible. I remember front-to-back lumber braces as well as the structural midrange tube enclosure which handle the heavy lifting. The baffle was 3" MDF laminated cross-direction. I remember a lumber transverse cross-brace in the lower area of the sides, but don't remember whether that made it to production. Memories fade. As a side note, the O3 and O3a & b had birch ply cabinets, but I think the CS3 &+ went to MDF. If I saw one I could reconstruct the picture. The 3.5 pre-dated Stereophile's review analysis (or Thiel's ability to do so) so we don't really know the nature of its resonance behavior. |
Please keep exploring options to improve the 3.5 including sourcing a durable mid range driver. As Tom reported before, it's only time before we run out of replacement kits. Several options have been indicated in the past but the specs of the 13m1852 are unknown for comparison to my knowledge. Anyone tried an substitute driver? |
Removing portability opens many options. There's a whole world to explore. Study before you play. Don't be fooled by heavy and hard. Concrete can ring like a bell. Etc. Etc. Etc. In the metals I would look at magnesium. Similar mass to stiffness as aluminum but higher damping - and much more expensive, of course. I really like the hydrostone / fiber thing I developed and was used on some Hales models. Tension skins on a different & multi) core has lots to recommend it. Remember that the air (acoustic) resonances are only part of the cabinet vibration problem. The drivers must mechanically couple to the shell for rigid launch. They bounce and propagate energy into the shell. Excellent idea is to oppose each driver with an identical one across the cabinet (as in front and back). Bummer is that you then have a bi-pole radiator instead of a point source, which rules out time & phase alignment. So I am opposing the drivers against a rigid vertical spine up the cabinet back. In a new design, that might be quite large. In extant Thiels it will be 1"x 1" and connected to every brace shelf and the cabinet back to damp it. A rod-strut connects each driver magnet to the rod for cooling and mechanical rigidity. I am exploring an outer shell for extant cabinets. Take a Thiel cabinet, add a few strategic braces if necessary, set the spine, screed non-hardening Permatex type 2 goo, add wood exterior to taste (3/8 x t&g strips). Viola! Inner structure keeps high integrity driver mount x acoustically stiff enclosure volume, and outer shell decouples surface resonances for less sound transmission into the room. No magic bullet. Plenty of room to play. Let us know your success! |
I'm curious about the ultimate performance speaker box. There's no way I'd ever spend 50k or more on a pair of speakers but I wonder if there are other, far cheaper ways to build the ultimate box out of readily available materials. There was a company that made their boxes out of layers stacked on top of each other with gaskets in between. The material used was some sort of epoxy I think. There were rods that ran from top to bottom that held it together and were screwed tight. It seems like something along those lines could be made fairly easily and the pieces could be made as thick as necessary to control vibrations. Heck, you could build the baffle and then make the rest of the box out of bricks. Put a platform with wheels on the floor and hire a mason to build the rest to spec. It could be curved or whatever shape you want. There'd certainly be no low frequency vibration there and higher frequencies could be managed fairly easily I'd think. Might end up looking really cool too. It wouldn't be very portable but might very well achieve ultimate performance. I have too much stuff floating around in my head and not enough time to play. |
tomthiel Never lame in any reply! The 3.5 is still beloved in 2018 and your hard work, labor of love, proves this fact. I must report that spending all of these years in the Audio forums, (2) models are at the top of the Thiel catalog. The 3.5 and CS 2.4 loudspeakers. And for excellent reasons- I can certainly vouch for the 2.4, not having heard, the 3.5 model. I concur about sealed Bass enclosures, when executed the right way, very musically pleasing than any other cabinet design. Natural Bass is the flip-side of this particular coin to me as well. Nothing like it. Keep up the commentary and correspondence here as your time permits. I value your input, always! Happy Listening! |
This answer may be a little lame - but here it goes anyhow. Note that I have been away for decades and my personal experience listening to music through a robust system ended with the 3.5 and the following 2.2. Now I have PowerPoints and 2.2s and have heard a few systems when visiting folks. So my experience is rather dated. But it was full-emersion / intense. So my reason for loving the 3.5 is personal. I was intimately involved in its development, parts sourcing, voicing, manufacture and tweaking. Those 3D baffles were all hand-carved by . . . moi and an assistant, in an amazing hand of man effective method . . . and then tooled on a vintage inverted router (souped up with an 8" diameter forming tool that I designed. You get the picture, full frontal engagement. The fiber (silk, paper) upper drivers do not have the resolution of metal, but they are more forgiving. The woofer was our first polypropylene and we custom designed the cone profile for significant breakup improvement. The caps in the 3.5 were Solen when Solen was using their own best-in-world French film. The micro bypasses were 1% styrene x tin foil. Lots of tweaking and voicing and audiophile sensibilities. Later products lost that last level of detail due to cost / value engineering. There just wasn't enough improvement for the considerable extra cost. Also the newer metal drivers changed the cost / performance equation again and caps suffered - inserting a little vague jangle, in my opinion. I have always locked on bass authenticity from my musician and recording days of youth. The 3.5 sealed bass has a rightness from the very bottom that just doesn't quite bloom with reflex bass. OK, the reflex bass hits all the adjectives better - tight, punchy, etc. and plays more than twice as loud. But the sealed bass of the 3.5 and 5, digging lower than the recording, somehow lights my fire more naturally. To your question. New Thiel models and generations always mitigated the problems of the previous generation and improved everything they addressed, within the limits of balanced performance. I think a newer, bigger model would almost always please more people more often. Try to audition some. The gist of my quest is to resurrect some of the old models which can be had at bargain prices and apply lessons and technologies to make them shine brighter than they ever did, and brighter than so many other contenders that don't deliver the full, broad, complete parameters that Thiel brought to light. I hope to conjure those last ineffable nuances of music. Love is a personal thing. |
Hi Tom, I managed to track down the previous owner of my 3.5’s, which I bought from a vintage audio dealer/repair shop. He was the second owner, having moved on from them to 3.7’s. He is also the original owner of CS5’s that make up his big-room system. He’s also has a pair of 2.3’s in his basement. He’s a frequent lurker of this thread. Anyway, you’ve professed quite a few times of your love for the 3.5’s. The reason I bring this up because this gentleman also told me that he misses very much the 3.5’s sound...that, to him, they have a different character from other Thiel designs/models. He likened it to the 3.5’s having a wide tolerance for genres...it was a speaker that played everything very well. If I may ask, what about the 3.5’s make you love them so? Because, while I LOVE my 3.5’s and have built my system around them, I often wonder what I would get by moving to a bigger Thiel? Thanks for all your wonderful input on this thread... Arvin |
"There's a thousand ways to lose a horse-race". New Thiel knew lots of them. Yesterday I spoke with Bob Brown, an industry veteran who was brought in as COO at the beginning to help navigate the new waters. He remains frustrated and somewhat angry today. His tenure was 2013. Regarding class D amps: In the mid 80s Jim began working with a very talented design engineer at Vifa who made all our custom-designed-from-the-ground-up drivers at the time. They co-developed the 1000 watt amp for Thiel's first subwoofer. It was class D before B&Os and other patents. At that time switching distortion was significant enough to relegate its use only to deep bass. But, I confidently speculate that Jim would have continued to improve that form of amplification for powered speakers, if Thiel had successfully cultivated internal design talent. Remember that Thiel's first Model A speaker in 1975 was an active 3-way with 3 amps and active xos. We never marketed it due to our internal limitations, and bucking the established passive topology paradigm. Rob says Jim's sub amps sound better than the subsequent BASH-Canada amps which are dubbed x.2, as far as I know. Anyhow I have collected an SS1 and three SS2s. A pair, broken and working, is being evaluated by my new tech partner for possible reverse-engineering to become a repair station for those amps. I'll report more when I learn more. Similarly, this forum led me to a reverse-engineered schematic for the CS3.5 equalizer. Thank you unsound. The repair shop will also evaluate a borrowed EQ for potential improvements. For starters, I see plenty of caps and resistors plus the phono jacks and switch points which could be upgraded for cleaner signal, short of the fully balanced option. That project is in incubation. I suggest that merely separating the woofer from the upper drivers (as in the CS3) would keep the boosted bass amp out of the detail range. Cleaning up the EQ components would bring life to the woofer. Remember that at 6dB/octave the upper end of the woofer makes contributions through the entire midrange. I suspect that Rob can help with the dual binding posts. Cardas and others supply good jacks. The cut switch may be good or may be upgradable - DIY project for someone here. Also, someone here might report on resistor and/or cap brand or type. Investigation required. I will explore these areas with my tech shop, but input is welcome. While we're at it, can anyone supply a schematic and/or photos or other information re the 3.5 XO schematic? But, but I'm not working on that model. But, I do love it. Oh the conflicts of the head and heart. |
There's a much sought after, classic Conrad-Johnson Premier 350 (350w) amp for sale right on on Agon! A number of Thiel owners over the years have thought this was the best amp they ever tried on Thiels. They don't come up very often and if timing were better for me I probably would have snatched this one up! |
I think the new owners may not have understood the nature of the speaker market. In speaker designs, there are a lot of good brands. If you want something, most likely there are ten brands will compete to offer you that "something". So it's not like there is a shortage of speakers out there. And each brand already has its own loyal customer base. The new Thiel attempts to build speakers that may be good in themselves, but they are no more special than what already available out there which themselves already has its own followings. Why would the existing customers have to take a chance to purchase the new Thiel speakers while they already know their current preferred brand fairly well? It's hard to build up a brand image that people can identify with, especially in the speaker industry where most stuffs are more or less a commodity especially at the price point the new Thiel was trying to compete. It's tough to compete in that segment. Someone once told me that if want to go into doing business, target either the very high end or the very low end. The middle end is very tough. It seems like the new Thiel strategy was going for something in the middle in both price and technology - just another headwind for them. The old Thiel although in term of pricing, it is somewhat in the middle but it's technology was at the very high end of the market. I've seen some very successful brands such as Dynaudio, B&W, Spendor, Sonus Faber and so on ... I think part of their success are as much on life style as their sound. People buy them for decorative purpose as much as the music. Seems like the new Thiel was trying to position themselves into this market but I guess it didn't work out for them. |
Can you imagine if they would have taken the cs5 and did the improvements tom talked about removing the bucket brigade resistors, up shimming the woofers and setting them up for bi amping! Using the new speaker material technology! How would that Have been for a flagship model ! Oh What could have been! |
I'd guess the reason the 2.7 didn't get a Stereophile review was because Wes Phillips had stopped writing. He reviewed the 3.7 and I think bought them. He reviewed a lot of Thiels over the years. I think by the time the 2.7s came out he was in poor health. He died a couple of years ago. The Thiel TM3 stand mount and the aurora portable speakers have been on Amazon for a long time. Overpriced, though. No reviews on any of them so I don't think anybody is buying. If they really have a big inventory of all of the newer Thiel lines I'd bet those will be real bargains at some point. Overpriced at 5k is probably great at $1,000. It's been a while since a lot of gear ended up on the market at crazy low prices. Maybe not since Tweeter closed. |
Judging from the Stereophile review and measurements (never heard on for myself), the New Thiel TT1 seems like a competent design. But why buy one? If I want a competent (but still sourced from the Far East) speaker using "conventional" engineering I would just go with something like a Revel (better yet, the Canadian made Bryston). It is not surprising to me that the New Thiels were duds at the dealers. On an alternate timeline, New Thiel continues to make CS1.7, 2.7 and 3.7, perhaps increasing the parts quality in the XOs much like Tom Thiel is proposing for the legacy Thiels. But even this would eventually need an engineer to keep advancing the product line . . . while staying true to Jim Thiel’s basic design principles. That said, we Thiel owners are fortunate to have Rob Gillum available with service and parts, as well as a potential upgrade path via Tom Thiel’s mods. |
In my opinion, there was room for Classic Thiel to improve and grow dramatically within the parameters of the original design thesis. Imagine coherent offerings designed around the last-generation coincident drivers with additional coincident lower midrange, active throughout or an amplified woofer section - higher impedances through improved drivers requiring less compensation - carbon diaphragms with integral voice coils, and so forth and so on. Expand the niche to include high-end recordists and ultra performance luxury goods for the elite and perhaps . . . who knows what. All could be done on the shoulders of Jim's work and in harmony with tens of thousands of extant customer base. |
prof - When Rob bought the Thiel service department earlier this year, he saw the New Thiel inventory and they said that 3 pair had been sold. Perhaps a few more since then. New Thiel missed the mark, failed to identify the narrow Thiel niche, and that extant conventional speakers covered the other bases completely. Three was not a typo, it may be incorrect, but it is in the ballpark. Lots of stock remains. The 3rd Avenue towers got 5 stars from a Stereophile reviewer. New Thiel had design and engineering talent and resources to do the job well. Their crossovers are assymetric/variable pitch as required. They may stand up well against other non-coherent offerings on the market. That stock will be liquidated by the court at probable pennies on the dollar. |
Tom, It’s helpful to read what you wrote about my turntable base. It represents the ideas I vaguely grasped while putting together the base, so it’s nice to see it gain some confirmation from a pro. I’ve always been curious how many of the post-Jim speakers (e.g. Mark Mason designs) Thiel ended up selling. (And if they had any stock left). I think they were designed to order. It's interesting no owner of those speakers have found their way to this thread. Though I'd have to guess they wouldn't be the typical Thiel fans to begin with. |
The side walls of the 2.7 are a smaller clip of the actual 3.7 panels, composed of multiple woods in assymetric layup with constrained layers - a technical tour-de-force for some high-buck brands to drool over. Thiel vacuum bagged the finish veneers, which they laid up in-house, onto those panels in-house. Past tense seems a little weird. Curved walls geometrically resist standing wave resonance. Great idea, very difficult to make work. Imagine aligning everything for assembly! The 3" baffle is MDF - which is nicely internally damped and pretty ideal except for the less than rigid driver recoil-launch characteristics, which I am addressing with penetrating hardener in and around the driver-mount recesses. No end to the fun. Thanks for the 2.7 review leads. It is peculiar that Stereophile never reviewed it. The Thiel Audio company was sold within months of the 2.7 release, which may have broken the long-running history of mutual appreciation between Thiel and Stereophile. From the very beginning, Stereophile appreciated our efforts and consistently validated our results. I consider the review journals as among the best allies one could dream of. prof - congratulations on your turntable isolation. Speakers add to the difficulty of managing isolation, the control of driver recoil and reflection-vibration, but without the luxury of isolating them from the cabinet which also serves as their spatial reference. Driver bounce reduces sonic incision. You picked good materials for your isolation bases. Among woods, the maples have high internal damping which increases as frequencies descend, which is unusual and helpful in your situation. If your annual rings were running vertically (turntable-floor) then you minimized the sonically transmissive structures in the wood. As I mentioned, MDF is nicely damped. Two different thickness is a very good idea. By adding the SS bottom, you set up a wildly different resonance scheme, causing an impedance mis-match which serves to damp transmission. And because of the high tensile modulus of the steel, you turned the whole sandwich into an assymetric beam in bending (assuming the SS is fixed to the MDF.) Materials with very different characteristics and dimensions works wonders. Cheers |
@prof thanks for those links. No wonder I never saw those reviews. I haven’t read TAS in years, their credibility is near zero, IMO. And hometheaterhifi is not one I look for. I didn’t read all of those links but they do say that the sides are plywood (that veneer job must be interesting) and that the baffle is 3” but without specifying the material. Hard to imagine that thickness would be any other than MDF. Tom has an idea to identify cabinet surfaces with resonance issues but I was unsuccessful at helping him with my setup. |
beetlemania, Thanks. Yes the 2.7 was reviewed in a number of magazines, in the USA, Europe and Asia. Some here: https://hometheaterhifi.com/reviews/speaker/floor-standing/thiel-cs2-7-floorstanding-speaker/ Absolute sound (made the cover): http://www.hificlub.pl/sites/default/files/marki/broszury/cs_2.7_the_absolute_sound.pdf Europe: http://www.hifitimereview.com/thiel-2-7-english/ Asia: https://translate.google.ca/translate?sl=auto&tl=en&js=y&prev=_t&hl=en&ie=UTF-8&...= Owner manual, info: https://soundapproach.com/pdfs/CS2.7.pdf |