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I have been an avid fan of Quad electrostatic speakers since I got my ESL-63 back in 1989. I could not understand where all this negative words about broken panels came from, my 63's had no panel problems under the more than 20 years I owned them. And I haven't heard any speakers that sound better, apart from the of lack sub-30Hz bass and high SPL:s we all know are the limitations of Quad ESL:s.
Enter the 989.
I upgraded to the larger version in 2014 after having used the ESL-63 with Gradient SW-63 (2x12" woofers) for some time. I wanted a less "complex" system, and did not need the bass performance of the Gradients for our music tastes. But these 989 was sent of for bad panels three times in a short time! I was beginning to see where all the bad reputation came from...
Out with 989, in with 2912!
I got angry enough to go on the phone and order a new pair of 2912, after having sent the 989 back and forth to the doctor just too much. Happiness entered our living room! The new speakers sounded perfect! But... a faulty panel showed its ugly face after some months. It was fixed under warranty. A couple of years everything was fine, and it happened again. This time they were repaired again, but paid by myself. No big deal, I thought it probably should not happen again.
But it did!
Here we go again. Same low level swooshing sound and silent pops from the other speaker! If somebody came around with just the tiniest amount of money I would let them go!
Why, oh, why?
Why can't Quad design speakers that I can thrust? Are there any speakers out there with very low distortion, but using ordinary dynamic drivers, that I can buy instead? I want to leave the world of Quad ESL!
Follow Ups:
To OP.
It disturbs me but I can't help myself...
Try easing back on the distance and/or pace. A hot bath with Epsom salts. Elevation and rest.
Sorry.
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I can now inform you, my friends, that a faulty bass panel is replaced by your truly (Yay!) and the speakers play just fine!
The hatred will probably fade away...
Thanks to Mrs S for helping me handle the fragile dust covers; they are really scary to move around!
PS. Our wizard, Mr Kentaja, told me that I can prolong the life of the panels by lowering the high voltage to the panels. I will follow his advice, it is a matter of a rather simple modification of the circuit.
I followed my study at a conservatory from 1975 until 1982. Since then I have been working every day with acoustical instruments. As a young boy I already hifi shows. After listening to speakers costing more than a sports car I always drove to my home thinking: If one buys a Magnepan 3-series you have all you need. Good luck.
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I have started my journey with the goal to repair my faulty 2912!
In order to practice, I removed the cover of the other, healthy, speaker. This speaker has a somewhat loose dust cover, which i would like to fix. I brought out all the tools, including a heat gun, and set off. Some time later, it was fixed! Yay!
But this is a risky manoeuvre, too much heat and you can say good bye to the dust cover!
Now it's time to assemble. And have lunch.
Until next speaker!
Per
Increase the value of the resistor in the HT bridge to lower the HT voltage a bit?
Yes R13 to be specific. The stock value is 61K in the 12 series speakers and this produces a bias voltage which is much too high IMO about 5.15kV.
110K-120K will drop the voltage to about 4.5-4.6kV which is the voltage that is found on early production ESL-63.
Yes I know the schematic states 5.25kV but in reality early production ESL-63 was much lower.
The lower voltage will reduce efficiency slightly, perhaps 1dB, but it puts far less stress on the panels.
QUAD raised this voltage over the course of the ESL-63 production to make them slightly more efficient in the hope they would ultimately play louder. This is speculation on my part. It doesn't really work for several reasons and the result is premature panel failure.
This increased voltage carried over to 98 series with the same result premature panel failure. With the 05 series QUAD reduced the voltage back down to early ESL-63 levels and I don't see panel failures due to drive voltage. Typical failure is glue issues which QUAD solved over a decade ago. I never see glue problems on late production 05 or current 12 series speakers.
Unfortunately and I don't know why QUAD has raised the voltage again on the 12 series speakers. This is a mistake IMO and the results are quite predictable.
Every speaker I service be it 63, 98, 05 or 12 series gets the bias voltage set at 4.6kV. And before I ship any new 12 series speakers that I sell I drop the voltage. After doing this simple change I have had zero issues with panel failures.
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"Yes R13 to be specific. The stock value is 61K in the 12 series speakers and this produces a bias voltage which is much too high IMO about 5.15kV.
110K-120K will drop the voltage to about 4.5-4.6kV which is the voltage that is found on early production ESL-63."
The stock value does not seem to be 61K, my schematic says 100K and on the PCB sits a resistor that seems to be 120K!
R13 is from 56k to 180k in schematics. 180k must be an error. Think I've seen 82k, too.
None of the schematics are correct for the HV bridge.
I have my 988s on the way for service in Germany. Are you 100 % sure of the 4,5-4,6 kV HT. Did you measure it?
Yes I have done hundreds of pairs and sold hundreds more EHT boards for DIYer.
I used to flip the board up to get to the backside to remove R13 and install a new resistor but that is a pain.
Now I just cut R13 from the board. R13 is located next to VDR1. The board has silkscreen component numbers.
Install a 1/4 watt 110K resistor to the yellow EHT wire from the transformer that is closest to the front of the speaker. The other end goes to the ground connection rivet on the board.
I had never heard of Quad increasing the voltage on the panels and that contributing to their lowered lifespan so thank you Kent for your information.
I was always under the impression that the main mode of panel failure on the ESL63 and later models was due to adhesive failure between the diaphragm and stator, even with the newer models. Can you discuss this failure mode and has it been alleviated over the years?
The ESL63s are my favorite speakers of all time but I gave up on them after getting panel failures maybe 10 years after I had all of them replaced. If your refurbs have long term reliability then I will be on the lookout for a pair done by you.
Yes the primary reason the panels have failed in the past is the glue not holding up long term. How long the glue lasts has been a bit of a moving target over the decades. Fortunately QUAD solved this problem 12-15 years ago. I have seen zero issues with glue failures from speakers produced from say 2010 to today.
The glue holds up nicely for ESL-63 production from the mid-80s to early 90s. Rarely do I see problems with speakers from the period. Before that and after I can guarantee the glue is shot even if the speakers are still working. 98 series had major issues with glue failure as well as early 05 production.
The secondary failure mode was excessive bias voltage on the diaphragm. ESL-63 production from the early 80s to early 90s rarely suffer from this issue. Once QUAD started to raise the voltage in late 63 production through 98 series production this has been an issue.
I use a high performance glue that holds up well I haven't seen any issues with panels I have rebuilt nor have I seen damage to the diaphragm from over voltage. I use a high performance glue and drop the drive voltage. I have rebuilt about 3,000 panels.
The current production QUAD panels are excellent the best they have ever produced. I am confident enough in their quality I now offer them to my customers as a service option.
Building an electrostatic is a tough business the reason few companies have succeeded in the long term. And the QUAD ESL-63 design is a particularly difficult speakers to build. QUAD made changes over the decades to ease production and in some cases the changes they made did not work well in the long term. The glue in particular is a challenge since that is probably the most labor intensive part of production. The glue is manually applied to the stator support matrix and this is a lot of glue and a lot of time to get it done.
A lot of good information, thank you.
I just sent a response. Please let me know if you don't receive the email.
As an authorized dealer and service center I never like hearing stories like this. I don't think it needs to be this way. But I never discount anyones experience.
I've been a huge QUAD fan since 1981 when I heard the original ESL. I was just a dumb 19 year old kid but wow I had never experienced anything like that before I was smitten instantly! I was working at the local high end dealer and we had all the top flight equipment of that era. Naturally that included QUAD.
I've been selling and servicing QUAD speakers for 20 years and have probably 700+ pair in the field after all these years. Have there been problems? Yes but very few. Thankfully. I think my failure rate is around 2%. I don't like that but failures are inevitable. I just had a pair of ESL-63 in for inspection that we did in 2008. They worked perfect. Many times when the speakers change hands the new owner wants to have me go over them. It's great to able to see how things are holding up over time.
Why are your speakers failing? It could be several reasons. I'm always happy to discuss by email or phone. It's a much too complicated subject to get into with on-line forums.
Thanks, kentaja!
I wrote you an e-mail with some thoughts.
Per
Your ESL-63's seemed to work fine for you. Do you think it was because you didn't run them full range?
Alternatively I wonder if something in your system is pushing your panels to fail prematurely.
When you transitioned from the ESL-63's did you change anything else in your setup?
Owning my Quad's since the 80's I've read and experienced some interesting things.
I've read they do not play well with some amps and to avoid certain cables because of their capacitance or inductance properties.
My Quad's can play louder and cleaner after I have cleaned all compoonent connections, contacts, tubes and sockets. Better signal and stability is a healthy thing. Maybe similar to how low wattage amps under distress can actually do more speaker damage than a more stable higher wattage amp.
Recent household purchases like appliances and HVAC have been affecting my system's overall sound. I did a few tweaks and nicely cleaned up what turned out to be electrical interferences with some of the components. I blamed panel failure in the speakers at first. Perhaps they would have been damaged if I let things go on longer.
Back in my early days of dynamic speakers and turntable rumble you wouldn't necessarily notice the flutter of a woofer unless the cloth grills were removed. I guess the point being that some things can be doing wear and tear may be going on unknowingly.
Jonesy
"I know just enough to get into trouble. But not enough to get out of it."
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I've owned several OBs starting with Accoustat 2 + 2s (with both 4 OTLs, and 2 interfaces), Magnepan 3.5Rs, and for 3+ years Emerald Physics 3.4s. Clayton Shaw recently introduced Caladans an open baffle for around $3000 that's well worth checking out
Edits: 03/06/24
Hi, Jonesy!
Thank's for your ideas on how to look for problems that has been detrimental for my later Quad speakers.
I have run all my Quad speakers from my Quad 606; it should not be a problem, I think. We have very few, if any, of electrical appliances that could affect the stereo system. They have not changed through the years, at any rate.
I think I just was very lucky with my original ESL-63!
Per
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You will never have panel problems again (15 years I've owned them, total age closer to 35 years, still sound awesome)...-...-
Panels in my Monitor IV's are 44 years old. I've owned them for the last 14 years and never ever any issue with them. I'm pretty sure the term "bulletproof" was coined to describe Acoustat panels.
is comparatively stout at 17 microns.
The Quad 63 is 3 microns while Sound Lab is 2.5.
I've got three pairs. Two pairs I've had for close to twenty years, the other pair for two. I've never had an issue with any of them. Fantastic sound and I suspect better than Quad.
Your interest may vary but the results will be same. (Byrd 2020)
I can't compete with the dead. (Buck W. 2010)
Cowards can't be heroes. (Byrd 2017)
Why don't catfish have kittens? (Moe Howard 1937)
No need to preach to the choir having owned them since '77, but availability isn't the same in Sweden.
What he needs is a Nordic kentaja!
nt
Thank you that is very kind!
Hi I hear your pain. I still have my US monitors after 30 some years. Also the full 66/67 system. I recently tried a dynamic speaker (PMC 25 26i) after having replaced a 9th panel in the speakers. Sadly I have found I could not live without my Quads despite their reliability problems. There is just something so right and natural about them. I have concluded despite my age I will keep trying to source and replace faulty panels. Perhaps QC is improving, we hope, and the panels will last longer. Best of luck in your new search. Gary
That in itself would be quite enough to turn me off.
Good alternatives are Magnepan, Martin Logan, Sound Labs (if you have the
money) and Sanders Sound Systems. There are others including the newer French company named Diptique which is apparently making some well received gear.
My sympathies as re: your problems.
Lack of skill dictates economy of style. - Joey Ramone
Thank you for your kind words about my situation and all tips on alternative speakers! As Roger points out, I have had thoughts on downsizing and buy smaller speakers with conventional drivers. The reason being that we plan to move to an apartment. But this is not happening just yet!
At any rate, there are certainly service organizations here in Sweden that can repair my Quads, it is just that I am a bit tired of sending them off; either by courier or stuffing the speaker in the family estate car. Instead, I have decided to cut a corner by disconnect the faulty panel!
Our very well informed forum colleague kentaja, answered my question "Can I just disconnect a bad panel in my Quads? " here back in 2016 (when I had problems with the 989) with yes, you can! Kentaja also noted that if it is a single bass panel, I probably will not notice any difference.
Also, a gentleman from Australia, Mr Christopher Mogford, has published a brilliant instruction video on how to disassemble the 2912 on YouTube under the name "Moggy's HiFi Antics". Perhaps Mr Mogford writes here, too? This helped me to understand how the speakers are designed, mechanically.
So I will try this! But don't hold your breathe!
I've had ESL63's and sold them when panels started failing. Then on to Apogees, sold them when they started buzzing.Now, running Acoustat 1+1 and Model 1. One can't believe these are 30 year old speakers and still in excellent condition.
Although these would be ideal for you (assuming you have 8-foot high ceilings), I know they are rare in Europe. Fortunately, there is an alternative: Audio Exklusiv ESL's. I understand these are easily available and inexpensive in Europe. They also have more modern technology than Acoustats. As for reliability, I would not say they would as reliable as Acoustats. However, they may be very reliable, certainly better than today's Quads.
Look them up.
Edits: 01/30/24
Dear Sir,
You have my sympathy. I have Quads (ESL(57) and ESL-63), and know they are certainly wonderful speakers. What you have gone through would certainly frustrate anyone.
Here in the U.S., we have excellent Quad service provided by specialists. I don't know what to tell you about restorers or service people in your country or any place to which you could drive or ship your Quads. Perhaps someone in Scandinavia will respond with a link to a useful restorer who can solve your problem.
If that doesn't work out, I suggest, as have others, that a pair of Magnepans might suit you. If you want something small their LRS would be a good choice. I had a pair of 1.6 QRs for a long time and really liked them. They are not too huge and their current iteration, the 1.7i, have been well received.
All the best to you!
I had the Ascents for almost 20 years and never had a problem. I washed the panels once a year and they sounded as good as new.
I now have 13a's and they are in a different league. I've only had them for a year but I doubt I'll have any issues with them.
My favorite ML was the Monolith IIIs. Also owned a pair of Prodigy's but couldn't wait to get rid of them
I had the original CLS model. For the first several months they were wonderful, if failing to provide much bass. Then suddenly they lost dynamics and detail, sounding somewhat "flabby".
The dealer could not repair them and took them back. Sometime later I read the mylar could stretch with use but could be repaired with a heat gun. I don't know if that was true but mine were gone by then.
I also owned Acoustat 2+2, two different speakers with the ESR-6 tweeters, and current the Janszen zA2.1, all trouble free. I've admired but never owned Quads.
"The secret of life is honesty and fair dealing, if you can fake that you've got it made." Groucho
There is an interview with Gayle Sanders where he says that the whole first production run of CLS started buzzing in the field after a couple of months and he had no fix! He did come up with something at the last minute but ML nearly failed before really getting going.
Those were RTR-6 electrostatic speakers. I had a pair of large RTR floor standing speakers which included a box on top with six (I believe) electrostatic panels. Also two pair (at different times) of Infinity 2000A which included those.
Some fairly expensive speakers utilized the RTR-6 for tweeters, including the Wilson WHAM and the Fulton J-Modular.
That was all years ago. Now at my age I might not hear them at all. :^(
"The secret of life is honesty and fair dealing, if you can fake that you've got it made." Groucho
Loved those RTR speakers too! I too had the RTR-6 tweeter add-ons as well as the Infinity 2000As.
ML speakers have come a LONG way since then.
I'm using BACCH4Mac processing with mine. Amazing.
The Quad speakers I owned happened to by present in my livingroom at the same time in 2016, before I sold the 63's and the 989's.
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Sad to hear this! Is the quality of Quad that bad nowadays? If you want to stay with planars, maybe Magnepan is an alternative for you? Some used 3.6, 3.7 or similar.
that is a "full range" electrostatic, it's hard to go back.
But the Maggies are at least a reliable alternative.
Maybe Sound Labs? Possibly Acoustat?
Sound Lab are far to expensive in Europe and very rare. Acoustat is very old and extremely hard to find. I know that Per also is thinking about downsizing, maybe not planars at all.
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