Thiel Owners

Hi everyone. I have been following this thread with great interest - thanks to Tom and the other very knowledgeable posters! I just brought home a beautiful pair of CS6's that I bought from a friend in Georgia (I live in Washington State) which tells you something about how much I wanted these speakers.

They sound amazingly good and are in near mint condition except for one problem. One of the woofers has a dented dust cap. About 1/3 of the dust cap is dented in. I contacted Rob Gillium (what a nice guy) and he can rebuild the woofer for $600. Again, the speakers sound great but my OCD makes me want to fix the woofer because it just bugs me. Will this damage make any difference to the sound? Could it cause the woofer to fail prematurely? Is there a good reason to spring for the 600 bucks and bring these speakers back to near perfect condition?

Any advice will be appreciated. Also, if there are any CS6 owners on the thread I would love to hear any advice you can share about setup or use of these speakers.

jafant - Thanks for starting a long and interesting thread. I'm driving my CS6's with a Krell KSA 300S amp and Krell KRC - 2 preamp. The amp is a perfect match for my Thiels because of their low sensitivity and difficult impedance curve. My other components include a PS Audio PerfectWave DAC and transport, a Marantz SA 8005 player for SACDs, A Krell CD 250/2 for HDCDs and I play vinyl with my vintage Denon DP 47F, Hana SL cartridge, and Krell phono preamp. I just bought a vintage Denon 3800 Blu Ray player so I can play DVD-Audio disks (I'm kind of a format junkie).

Good credible information in this thread about cables. I run a mishmash of cables including Audioquest, Emotiva, and Blue Jeans interconnects and Tara Space and Time speaker wires. I've just never been able to hear much difference in cables. One of these days I'm going to spring for a fancy power cord (probably Shunyata) to see if I can tell the difference but it's not a priority. One thing that has actually made a very audible difference is the addition of a BSG Technologies qol processor. This thing improves the imaging, particularly the soundstage depth, without causing other audible problems. It's one of the best investments I've made and it works great with the Thiels, which already image fantastically.

tomthiel - Thanks for the vacuum cleaner tip; I'll try it. Rob suggested using painter's tape but I couldn't get it to pull out the dent at all.

thielrules - This pair of CS6's came from Cumming and they weren't advertised. I bought them from a guy I met at the 2017 AXPONA and we have since become good friends. He upgraded to a pair of Legacy's and when he mentioned that he would sell me his Thiels for a good price I enthusiastically took him up on it. I had to drive to Rochester, MN for another reason which meant that I was only two days away from Cumming. If you ever need to know this, it turns out you can fit two Thiel CS6 speakers in the back seat of a Dodge Charger. No, it wasn't easy.

Hello again. My last post was in August when I talked about my newly acquired CS6's and the fact that one of them had a woofer with a dented dust cap. Tom and a couple other members gave some advise about using a vacuum cleaner or tape (Ron G. recommended the same things) but none of that worked. Whatever material that cone is made of is very stiff and didn't want to move. Due to my audiophile OCD I was seriously considering getting it repaired even though it sounded OK.

Well, through sheer stupidity and carelessness, I solved the problem. I was hooking up my Denon Blu Ray player to my PS Audio DAC and didn't mute the preamp. I sent a few seconds of loud digital hash through the speakers and blew one of the woofers. Fortunately the woofer that fried was the one with the dent. I called Ron at CSS and he patiently helped me through the process to get the woofer removed and sent in for repair. When I finally got it sent to him the turnaround was very fast. My speakers were out of commission for the last few months but last week I reinstalled the rebuilt driver and my CS6's are back in action!

In the meantime I worked my way through this entire thread and I have to say that this has been like a 400 level course on speaker design and construction (not to mention amps, cables, etc). Virtually all of the discourse has been constructive and based on first-hand experience. Thanks so much to Tom and the other knowledgeable participants in this forum. This has made me appreciate my Thiels (and Thiel owners) even more.

BTW, SNs are 1537 & 1538, Morado finish.

I will make some subsequent posts regarding my amateur speaker surgery and other relevant observations but again, thanks to all who have generously contributed your experience and knowledge. This is hands-down the best audio discussion I have ever seen in my 40+ years of this hobby.

Re: CS6 Woofer Rebuild & Replacement

I thought I would document my experience of removing and replacing my CS6 woofer in case there might be any useful tips for other Thiel owners.

When I figured out that I had blown my woofer I called Rob and basically asked, "What now?" Rob was very patient and helpful but I also learned a few tricks myself. Here are the steps I went through.

1. Lay the speaker on the floor on its back. Do not try to remove the woofer with the speaker standing up. Rob suggested it would be easier to do the operation if you can put the speaker on some sort of stand but I had to make due with the floor because I had no way to lift a 170 lb. cabinet onto a table, nor did I have a table that would support it. When you lay the speaker on its back it is really helpful to put a pillow under the upper cabinet so that the upper part of the cabinet is slightly off the floor. That's so that you can get your fingers under it to stand it back up again. I learned this the hard way the first time I laid the speaker down to hook up the spades to the terminals.

2. Have a thick cotton towel handy to lay on the face of the speaker over the mid/tweeter so that when you remove the woofer you have a place to set it without scratching the baffle.

3. The 9/64 allen wrench required to remove the screws is an odd size so you will need a complete set of SAE allen wrenches that include that size.

4. There are screws for the trim plate and then seperate screws that hold the woofer to the baffle. In the case of the woofer they are the same size. However I strongly recommend placing the trim plate screws along with their washers in a separate baggie with a label. The reason for this will become evident below. Remove the screws for the trim plate and be careful to remove and keep track of the tiny thin black washers. They like to fall into the cabinet and bury themselves in the insulation. If you lose some of these washers it is extremely difficult to find replacements. There are also tiny black rubber O rings which can also get lost. Those are easier to replace but still rare. Of course I would never be so stupid as to lose any parts like this but I'm pointing this out just in case.

5. Take a photo or two to document where the rubber o-rings go. Once you remove the trim plate and account for all the hardware you can remove the screws holding the woofer to the baffle. According to Rob I should have been able to get my old fat fingers to grip the edge of the rubber surround where it meets the basket and lift the woofer out of the cabinet. Forget it. Ain't happenin'. I was afraid I would damage the rubber surround so I called Rob back and asked if I could pop it out by removing the passive radiator and reaching around to get under it. Rob complimented me on my speaker repair ingenuity and agreed that would work.

6. To remove the passive radiator you need to remove the trim ring and then remove the radiator. The screws for the trim ring and the passive radiator are different lengths. IMPORTANT: Keep the screws separate and label them along with their respective washers (both metal and rubber). Steve put them all in the same bag. Steve used the wrong screws to reinstall the passive radiator. Steve broke the passive radiator. Don't be like Steve.

7. Even when I had access to the bottom of the woofer I could not lift it up out of the baffle. It was stuck. Fortunately there is a brace that goes under the woofer with a inch or so clearance. I used a plastic scraper to apply some leverage between the brace and the woofer magnet and popped it loose. Then I figured I could lift it out as Rob had recommended. No effin' way. That sucker is heavy and it didn't want to budge. I was able to push up the bottom of the speaker from inside with one hand and get my fingers between the basked and the baffle with the other. Then I could get both hands under the baffle, lift the speaker up and out, turn it over, and set it on the towel face down. There is enough wire to be able to do this.

8. I am an absolute novice when it comes to soldering so I watched a couple of Youtube videos and got myself a 25 watt Weller soldering iron at Lowes. Rob had noted that they use silver solder which has a higher melting point so when I went to desolder the wires from the speaker terminals it took a little time before the solder melted but when it did the wires came off readily. The wires from the crossover were crimped around short wires that were attached to the speaker terminals in a simple arrangement.

9. I followed Rob's directions about packing the driver because if it breaks in shipping it could be very expensive to fix. The repair was $600 on a sound driver - I would hate to know what it would cost to fix a broken one.

10. CSS had the driver fixed in several days and sent it back. Rob sent some silver solder to reconnect the wires to the speaker terminals. I cut off the ends and stripped the wires, crimped them around the woofer wires at a 90 degree angle, and soldered them in place. With a low wattage soldering iron you have to be patient but eventually you heat up the wires enough to melt the solder and make a good connection. At least I took a photo and noted which crossover wire goes to which driver terminal. C'mon, I'm not that stupid.

11. Replacing the woofer back in the baffle was pretty simple. There are metal inserts in the baffle material for the screws but I suspect you have to be really careful to not overtighten them. Hopefully you noted where the washers and rubber o-rings go so you can put them back properly.

12. When I replaced the passive radiator I used the long screws to fasten the trim ring. I heard what I thought was a couple of cracking noises so I stopped and took it back out. The screws bottomed out and stressed the soft wood of the radiator and cracked it. The unit was still intact but there were cracks. I gathered up a bunch of clamps and carefully applied wood glue to the interior of the cracks with a toothpick and clamped it all the way around. I'm comfortable that it's as good as new, but damn, I was pissed at myself for making such a dumb mistake. My mood changed considerably when I fired them up and they sounded wonderful. I think they sound better than they did before but that's probably my imagination.

The moral of the story is that we are very fortunate to have support for decades-old highly custom designed speakers for which the manufacturer is out of business. I'll add my voice to the chorus of shoutouts for Rob - he was an absolute pleasure to deal with and I wish him a long, happy, and profitable career in giving extended life to these amazing speakers.

Re: CS6 Data Point

I wrote Rob a short note and asked him what he could tell me about my CS6’s - SN 1537 & 1538. Here’s what he said.

The CS6 was in production from 1992 through 2009. My pair was built around 2005.

There are a few versions of drivers and crossovers for the CS6 but mine are the latest version.

I asked Rob if he had developed any "hot rod kits" for the CS6 and he said that changing any parts to the crossovers have proven to reduce the performance. He added that he felt that Jim had pretty much optimized the design of that particular model.

I’m surprised that the CS6 had such a long manufacturing run (17 years). It seems to overlap somewhat with the 3 series but obviously it held its niche in the product line.