Good to see you again. Thank You for the comparison and update on your 3.5 loudspeakers. Rob is the man when it comes down to our beloved speakers. Also good to read that your amp project turned out well.
Happy Listening!
Thank You theaudiotweak I've already ordered some Mills resistors for the tweeter to test to see how difficult it will be to remove the old ones from all that glue . I'm doing the wire first so I can install fastons for the wiring so the boards can be taken out to work on easily , I'll remove the fastons and solder the wiring last . Plus it will give me more time to gather information and advise . |
Well you would have 2 conversions when really only none is required..And you would have many more component parts including the probable use of a couple of noisey switching power supplys. Other than that it would work. I have run digital eq and xo on my system once and only on the subs which I quickly removed. Tom |
vair68robert..Just saw the exposed crossover you posted. The single easiest most dramatic improvement would be for you to replace all the resistors shown with either non inductive wire wounds from Mills or Mundorf. I would replace the resistors first before the wire..You will always hear the resistors shown and their low level noise will still be present in any wire you try. Change the resistors first/next.. Tom |
Get it all out here..When I did a remodel of my power amps I took the main board Nichicons off and chassis mounted 4 of the Clarity Cap TC's these are hard mounted to the metal bottom with Audiopoints. You could do the same in a speaker when replacing a large value cap. These caps a very nice up grade. Flys high now with the Vishay nude metal films in every position.Tom |
Question can you run a cap and resistor in series to equate the the esr of the original ? @theaudiotweak Yes, you can, though ESR is not exactly a constant at all frequencies, you can definitely compensate with a little eye balling of the relevant graphs. :) 0.1 Ohm difference isn't as important as going from 1.5 Ohms to 0.3. That in shunt can really drop the impedance of the next range. Not as fancy, but I love Mills. Small, very high power, extremely accurate and thermally stable. Remember the same thing with inductors. Keep the DCR the same, or you are changing the speaker. There are a number of designs (including my own) which use the DCR as part of the baffle step compensation. Best, E |
Question can you run a cap and resistor in series to equate the the esr of the original ? The best sounding resistors are the Vishay nude metal films. When I rebuilt my long gone Dunlavys years back..I had to build resistor bridges with several of these low wattage resistors to meet the power requirements. The improvement was almost staggering well that and sealing all the pores of the MDF inside of the cabinet with Cascade Vbloc..the formula now is a little different. Kinda like troweling on concrete. Sucks in and seals and kills the glue..Much more dynamic and open. I sealed 1 and kept quantity measurements, let dry for a few days and reassembled and compared..The treated one sounded like it went out the door and down the street..the other one was still in the box. The pair was amazing. My experience tells me not to replace inductors..go gently with the caps..and replace all the dime store resistors. Tom |
The 400uF electrolytic is in series feed to the midrange.Oh, wow! Welp, on the plus side there is more room for sonic improvement. But 400 uF of film caps will certainly need a new layout/board. And it looks like one of the other ELs is 220 uF. And not only much bigger but also $$$. My new boards were much larger. I compensated in the passive radiator chamber by removing a similar volume of the fiberglass batt. But I only had two 100 uF ELs to replace. 400+ is probably still doable but complicates the issue and makes the upgrade spendy. Clarity CSA 250V is available in 100 uF for $68 each. PulseX 250V is more affordable and should be sonically superior to ELs. Lean on Tom’s Knowledge, Robert! |
Rob and Erik - The 400uF electrolytic is in series feed to the midrange. Bummer Doh, then consider the Mundorf electrolytics: https://www.partsconnexion.com/capacitors-ele-mundorf-e-cap-ac-series.html or Axon film: https://www.partsconnexion.com/axon-true-cap-film-capacitors.html In either case, measure ESR of the original and be aware that reducing it significantly can result in more midrange output. :) Best, E |
Hello all, returning with an update on my 3.5 mids. I received them back from Tom this week and was able to do an A/B test with the original mids, rebuilt by Rob, and the
Scanspeak 12W/8524G00 speaker, which has been floating around on the web as a suitable replacement for the original Scanspeak mids. The replacements were in my 3.5's when I bought them, I was able to score the mids from a fellow Audiogon contributor and had Rob rebuild them. Anyway, I wasn't expecting much of a difference, if all, simply because I don't consider my ear terribly critical. I replaced on of the mids, put my preamp on mono, and played some ZZ Top (I am originally from Texas, so....) and did a close up comparison as well as sitting position in my listening room. I was surprised at the difference! The original Scanspeak obviously worked better with the crossover, the difference being that the rebuilt original was much clearer and articulate, where the replacement was subdued sounding. So what I thought was an excellent listening experience before the replacement has turned into an exceptional one. I kid you not. So I would say this particular Scanspeak (
Scanspeak 12W/8524G00) is not a good match for the original. I think Rob is recommending another one, and Tom may have something to say soon as well. Amplifier update, my last post was lamenting on the binding posts on my Yamaha M85 and Denon POA 1500. I replaced the posts on the Denon to 5 way, and sold the Yamaha and bought a Denon POA 2200, which I now need to replace its binding posts as it used the exact same one as the Yamaha. My only comment on replacing the bindings is I was scratching my head on what to use to replace the strip of metal between the old posts and the PCB. Then I remembered I had some romex wire from my basement finish work, so I stripped sections of the solid copper wire and used it. Worked perfectly. |
Hey @vair68robert Given the cap sizes you are talking about I'm assuming these are in low pass sections, and going to ground. The Solens, or their cheap brand, Axon, will be great choices, BUT, you must maintain the original ESR + R of that portion of the circuit or you may suffer unexpected impedance issues, which causes your amp to suffer, along with changing the crossover points. Save the top-end caps for caps that are in series with the drivers. Best, E |
@beetlemania You have seen one of my obstacles , one possible option is 2 Solen 200uf 400v large but the 400 is at the bottom of the board , Another is a Clarity TC 400uf 400v very large . I'm going to have to do a lot of measuring this project is going to take a lot longer than anticipated as well as way over estimated budget , but after rehabbing 2 100 year old buildings with 5 apartments I'm used to being over on time and money . |
Let me chime in as some one with relatively recent experience with Clarity and CMR in particular, but not with Thiel rebuilds. The CMRs are excellent caps. I honestly don’t know if they are better than the previous generation. I’ve swapped them out in my application and they sounded equally excellent. What I have found in both cases (CMR and MR) is that Clarity caps above 5uF benefit from a small bypass copper cap. This was a suggestion passed onto me at DIYaudio by Speakerdoctor before he passed (RIP). Though he did not suggest it above a certain uF value, I have found this to be about the break point. Below this value, a bypass cap did not help, but above it certainly did. Based on his suggestion I’ve used Audyn 0.1uF TrueCopper bypass caps, and they worked really well. Anyone who wants to ship me Jupiter caps instead please do so! :) I wish I could afford them. Best, E |
Jim never went over 100uF.Pic of @vair68robert coax crossover has a 400 uF EL. I know this crossover was designed after Jim passed. I imagine he will need to use an entirely new board if he chooses to replace that cap (plus a couple of other ELs visible in his pic, presumably >=100 uF). That would be quite the volume in film caps! But possibly worth it . . . |
I was at least able to verify that the original caps are indeed Clarity Caps SAs as I am almost certain that this is the first re-cap these 3.6s have ever experiencedYou must have very late production 3.6s. I would have guessed Thiel stopped making those before Clarity introduced the SA. Interesting. The SA is a good cap but, as Tom Thiel wrote, the CSA is a step up. The CMR is supposed to be even another step up. But those are much larger, possibly requiring a new board to accommodate their size and much more expensive. My new boards have 630V versions of CSA on the coax feeds. It would be interesting to compare 630V CSA to 400V CMR. There is a 630V version of CMR but those are bigger still and more expensive with a smaller range of available capacitance values. You probably have high quality coils but I would replace any sandcast resistors with Mills MRA-12s. |
Thought I'd pass along my rudimentary update on my exploration journey yesterday. I managed to remove the woofer with much labor. I ended up removing the 6 screws and placing the cabinet, baffle down, on the carpet propped up with a book on the top side. Then I ran a 40 hz tone from a generator at about 90 db to vibrate the woofer from the cabinet. It took about 20 seconds! Not sure if this is text book operation and hopefully not damaging to the components... Anyway, I was at least able to verify that the original caps are indeed Clarity Caps SAs as I am almost certain that this is the first re-cap these 3.6s have ever experienced. As I am a musician by trade and quite the amateur with regard to electronics, I continue to welcome experiences, anecdotes, and any tricks you may have as I continue on my journey. I am handing with a soldering iron though. I would image that the bulk of the laborious work removing the remaining drivers and components will need to wait for a few weeks while I finish up my online spring teaching schedule but have plenty of time to dig in later in June. I did have a chance to look at the Carity Caps website and found the CSAs with ample information. I also found a next gen CMR: http://www.claritycap.co.uk/products/cmr.php Have any of you guys had experience with these? Also, while I have the crossovers out, what other electronics should I consider replacing that may need replacing? |
Beetle - I suspect the "don't do it" is because the spuriae introduced are evidence of non-linear behavior which can cause problems for some amplifiers. Rob - the only resistors that benefit from upping are those carrying current, which are in your stock pair. Plus a couple that I can advise on a PM. |
Tom & Beetle I am Happy to hear that you hear positive affects from the parallel configuration , I will try seperating them more than the 2"s I have them now . Thank you Tom for your advise on placing resistors parallel , there will be 18 resistors per speaker ! I'll have to do some similar parallel configurations with the electrolytic caps . Ons step at a time , espeacailly with all the glue they used on the componets . |
Rob and Beetle - I have also gone back and forth between wire configurations. My observations are similar to both of yours, the parallel configuration seems to add dimension and space. I hear more lucid harmonic detail such as obviously double strings on the mandolin or transient fingerings within electric guitar chordal work. And more lush and detailed (at the same time!) mid-bass. Such observations hold true blind. I have also done some measuring. The only obvious difference is the presence of large, broad "bloating" of sub-sonics, perhaps 10+dB at 10 to 20 Hz with frequency sweeps beginning at 0 Hz, with accompanying group delay anomalies. I am in conversation with Steven Hill of Straightwire as well as a knowledgeable physicist, plus my reading. Those expert opinions concur that whatever pleasant effect we are hearing, the technicals are more problematic. In other words: "don't do it". One interesting trial was controlling the separation of the ++ and -- cables. Consistent separation is a technical requirement. Separating at 1.5" (my convenient wood blocks), served to lessen the "effect". Also spiraling the two cables lessens the effect. And, conversely, the effect is pronounced with widely separated runs (1' to 3' along the 10' run.) I am getting some double helix wire from Straightwire where 4 conductors will carry the signal in star quad (opposite corner) configuration. This configuration is standard practice in studio cables, house wiring and industrial practice. For my own listening I would choose the separated parallel conductors. Thank you Rob. However, my upgrade work requires science based solutions. I'm still working on the problem. |
tomthiel Thank You for the confirmation regarding Clarity Caps. Hope that you are well and having fun splitting duties between Hot Rod garage and Studio time. If you guys require more specific(s) relating to Clarity Caps, reach out and touch Dave Garrettson, whom represents that brand here on the 'Gon. Happy Listening! |
@vair68robert I switched back to the parallel ++/- - configuration a few days ago. I do hear this as more open and dimensional, less bounded. Could I pass a DBT? I dunno and I don’t care. If I were more motivated I would compare in mono. But that requires removing the outriggers and spikes and a couple of hours of swapping speakers back and forth. I’m not saving the world here, just maximizing my enjoyment. Now, I need to decide whether to resolder the binding posts so that the cables are not off the ground as much. I will not be enjoying anything if a house guest trips over the elevated cables. |
@stspur I built completely new boards for my 2.4s last year, with guidance from Tom Thiel. Excepting for a few bypass caps, everything is Clarity Cap CSA. Higher voltages on the coax feeds. Even the big 100 uF shunt caps are now CSA (low voltage). Jim Thiel and crew picked the Clarity SA for the 2.4 SE out of several compared. The CSA is an upgrade from the SA. Also, the CS2.7 includes some Clarity caps, maybe ESA which is between SA and ESA. |
Hello again fellow Thiel 'Goners! Glad to have your continued advice and experiences with our beloved speakers. Always a joy to catch up on what's being newly discussed. I'm considering updating my original CS3.6 crossovers and was thinking about starting with caps. Would you have some recommendations for me? I was thinking along the lines of Infinicaps or Obligatos. Thoughts? |
CS3 lovers - just saying that the CS3.5 is really a CS3 with more sophisticated drivers. Same concept, functionally same cabinet. Any future life we develop for the 3.5 will apply to the 3. We have a good midrange replacement candidate. A replacement tweeter will be easier to find. The woofers are battleships and repairable. The real issue with the equalized sealed-box 3s is that the boosted bass can bottom the woofers, and also puts real strain on the midrange. I am working toward keeping the sealed bass as-is (unequalized) and augmenting with a subwoofer crossed over to match the natural second order bass roll-out. That frees the 3 drivers to operate in their natural range for lower distortion and longer life. I now have a pair of CS3.5s, and they really are quite good, especially for 1983 (CS3) and 1985 (CS3.5). |
utrak glad to hear that your 3.0s are now back to full life, as they deserve. I guess that Rob Gillum at Coherent Source Service is the only one that can provide the right spare parts nowadays. I purchased a full set of spare driver for my 3.6s because my intention is to keep these speakers lifetime, no other Jim Thiel in the view for the moment, he was not one among others, he was a unique talented engineer that we miss, a lot. Luckily we still have Tom, his brother as part of living history of this amazing brand, thanks Tom being so active here, thanks Tom being so active here, your competence is great as your humility. Even if I gonna to buy another pair of top speakers in the next future, something based on trasmission line with 18" woofer Thiel will remain with me. |
Hi Everybody, About a year ago, I posted about a problem I was having with my Thiel CS 3.0s that had not been used for many years. The soundstage was off and it seemed to follow the speaker. It wasn’t obvious whether it was the crossover, midrange, or tweeter. Well, after a lot of help from Rob Gillum at Coherent Source Service, I was able to determine that it was the tweeter. I also verified that the 36-year-old crossover was in great shape and all of the caps were in spec. The rest of my system now consists of a PS Audio PWD II w/bridge, Dodd battery tube preamp, and a Pass X150.8 amp, which replaced a pair of ASL Hurricane tube monoblocks. My acoustically treated room is small (11’ x 16’ x 10’) so I’m not using the bass equalizer. I also use REW room correction software. After installing the tweeter that Rob sent, I think that my CS3.0s sound amazing, especially considering the fact that they are 36 years old and 5 of the 6 drivers and the crossovers are original. I also wanted to thank whoever brought up the OCOS speaker cables earlier. I have a 30-year-old triple run pair that I wouldn’t have considered using had it not been for this thread. I installed them and they are definitely better than the off-brand cables I was using. I guess that I’ll have to throw in the Magnan Vi interconnects next 😊 I was trying to find a pair of 2.4s but the 3.0s sound good enough for me for now. Thanks again everybody, utrak |
dsmarschall welcome into Thiel's family, you will be pleased by your "new"fantastic 3.6 as I daily do. If I can, and whether you plan to keep these jewels for long time, I suggest to purchase some strategical spare driver as I did, one tweeter and one mid, they are the most critical parts in this wonderful project and the "real" original drivers start to be very hard to find due to the poor stock available nowaday, furthermore keep in mind that only the original part number will assure the sound performance as intended by Jim Thiel. |
@beetlemania I have thought of a way to connect the wiring with faston connectors , I'll attach the female end to a 14 gauge solid wire that is soldered in/on the soldering rings and the male on the wire . This will allow me to install the wires first and be able to remove the boards as I replace componets . I'm also thinking ( again ) of using the 15.5awg , partconnexion has Cardas wire on sale $1.95/ft ( I buy it from Michael Percy with price matching ) . you can contact me by e-mail ( from page 155 ) . So far it looks like the total cost would/should be $600 max to be spread out over 3 or 4 months , not bad considering that over 8 months I spent $1300 on the amp . Rob |
@vair68robert Sounds like you have a solid plan for an upgrade path and Tom might have some ideas for you. Here’s my two cents. Do you have the schematic? If you’re on a budget you should target the parts in the feeds, rather than shunts, and prioritize the coax filters over the woofer (CS2.7 has electrical XO for the coax, right? CS2.4 coax is mechanical). That said, I was able to hear a difference among two voltages of otherwise identical capacitors in the woofer shunts, so *everything* should be assumed to make at least some sonic difference. I recommend replacing as many resistors as possible on both boards as this makes a nice sonic difference for relatively little cost. Some of the CS2.7 values cannot be matched directly with MRAs, you will have to get creative with parallel and series replacements to get the correct resistance and power ratings. I noticed that PartsConnection has better pricing than Sonic Craft right now. Clarity Cap CSA is a great sounding cap and a good value. Higher voltage has thicker film and this is desirable for the midrange where our ears are most sensitive. The downside is higher voltage caps are larger and more costly. CMR is said to be a step up from CSA but I haven’t heard these. You might also consider a bypass (1% or less total capacitance) on coax feed caps. I used Multicap RTX and heard an improvement in transients and, maybe, improved resolution. I was curious to also try CMR (Tom offered that as an option), Audyn True Copper Max, and/or Jupiter copper foil as bypasses. I dropped those plans after I put in the Cardas which just put the “cherry on top” of all the sonic improvements I heard along the way. A couple of other things you might consider . . . 1) electrolytic capacitors will drift with age and this type is sonically inferior to film type, even if in a shunt position. The downside is replacing ELs with film is costly and requires far more space. You would need to make an entirely new board to replace that 400 uF EL with film caps. 2) Foil inductors are said to be an improvement over coils. I have ERSE FoilQ in the feed paths for both the coax and woofer boards. I did not make this particular sonic comparison, however, because I replaced the caps and inductors together. Finally, Tom had cautioned me that such wholesale replacement of parts could upset the sonic balance in unpredictable ways and that one check was to compare the total resistance of the circuit before and after. I didn’t do this until after I replaced all the resistors but my final boards are within 2% of both the OEM boards with Mills MRAs and the values on my copy of the CS2.4 schematic (the CS2.4 woofer filter is almost a flow through, <1 ohm). |