Quad ESL Question

Jazzman53 · « **Reply #60 on:** 17 Aug 2015, 06:57 pm »

Great news Steve,
Those speakers are so directional you have to hear it to believe it (and beaming isn't a bad thing!).
I have no doubt your 10C's sound fantastic, properly setup.

I relied heavily on Sanders’ design principles for my beam-splitter transmission line hybrid ESL’s and they are pretty amazing too. When tweaking mine I also did exact physical measurements for distance and aiming and also used the DSP’s digital delay to exactly time-align the woofers to the panels. It was Roger who talked me into tossing my original analog active crossover and going full digital-- and wow!

steve f · « **Reply #61 on:** 17 Aug 2015, 07:23 pm »

Jazzman,
I have to tell you about how I ended up with the Sanders speakers. Roger is a great guy. I wrote to him about my AXPONA experience of his room. My son and I had just walked in. An orchestral piece was playing. I told my 35 year old son to sit down and listen, that's what an orchestra sounds like. (Ever the dad telling my kid what to do.) When I started getting into the failing Quad 989s, I found out that nobody who did repairs, wanted to share their 'secret sauce' recipes with me. Roger wrote back about my rave review, and kindly offered to answer any ESL questions I might have. We exchanged a couple of emails about the Quads, and talk about enlightenment, I was now pointed in a good direction. He added a ps that there was one pair of 10C speakers left, and would I be interested in giving him a bit more warehouse space? We made a deal, thanks Roger, and I am a happy camper. Too bad I couldn't afford a Magtech amp. I'll have to save up for one.

Who knows, perhaps one day I'll get a chance to listen to your speakers. I'm sure they sound fantastic.

For anyone on the ESL fence, you have to try them. As good as planar magnetics are, and open baffle too, I find that only ESLs and some horns have that jump factor live music has.

steve

AKGman · « **Reply #62 on:** 9 Dec 2018, 02:07 pm »

I have a problem with the ESL-63 (on only one of the speakers). There is continuous scratchy/static extraneous noise after it is plugged in and turned on (but the speaker still sound good otherwise). But there is no noise when the power is unplugged (as is normal for the 63, the sound coming from my CD player, via the RCA cables, continues for a while, even after power has been unplugged, but there is no more extraneous noise once the power is unplugged). The orange neon light is flashing quickly, which would indicate a bad panel (?)

I have taken the fabric cover down, and shined a torch on the inside, and the only unusual thing is a black 1cm in diameter on the stator (I assume the bronze mesh with round holes is the stator). It looks like a burn mark. Can I keep using the speaker for the time being without making it worse? Can anyone please tell me what is going on?

Jazzman53 · « **Reply #63 on:** 9 Dec 2018, 05:13 pm »

If the scratchy sound occurs when the speaker is plugged in, with no music playing, it's the bias voltage arcing, either around the contact, somewhere along the panel periphery, or anywhere on the panel.

Since you have a black mark, which is no doubt a burn thru, the scratchy sound is most likely emanating from there, and is probably accompanied by a hole burned through the diaphragm. A hole (or even several holes) the diaphragm isn't a big deal per-se, as long as the diaphragm tension is maintained. It's the increasing arcing damage to the stator that's a potential problem.

There is bound to be at least some charge loss on the diaphragm, so I would bet the output is down a bit compared to the non-scratchy speaker, even if it still sounds OK. And it will get worse over time. Were it not for the and very high resistance of the diaphragm coating preventing the full charge from shunting to the burn thru area faster than the bias supply can maintain it, the burn through would have already killed the speaker.

If the burn thru progresses to arcing between the stators, rather than just diaphragm-to-stator, your amp will see it as a dead short. If you start to hear any high-amplitude pops, shut it down immediately or risk shorting out the speaker's step-up transformer and/or your amp.

AKGman · « **Reply #64 on:** 9 Dec 2018, 11:49 pm »

I don't know what would have caused the burn-through. I recently put the speakers in a cupboard for about a week, maybe that meant more dust got into them, and I was also moving the speakers around a bit to get them in there. But the speakers had been reconditioned by a professional earlier in the year (not long ago).

Thanks for your help. Do you think it would be possible to fix it myself? Or would I need to take it to a speaker repair shop? Should it cost a lot of money for them to do it?

Jazzman53 · « **Reply #65 on:** 10 Dec 2018, 04:07 am »

I've never disassembled an ESL-63 and I'm not familiar with its power supply, so I suggest you seek other advise, besides mine.

I have built DIY ESL's and I understand generally how they work. I suspect you have a panel going bad. And I believ the 63 has two bass panels plus a mid/treble panel in the center.

I think it's unlikely that putting the speaker in storage caused the problem, unless it was a very damp environment. Quad may have even enclosed the panels inside plastic dust covers like they did in the ESL-57.

A burn thru starts small and gets progressively worse; eventually causing the panel to fail. I've heard of people repairing a burn thru by overcoating the burn area on the stator with paint or even clear fingernail polish-- but you would have to disassemble the panel access it, and then you would have to replace the diaphragm, spacers, and the diaphragm coating. And to do that you would also have to know how much to tension the diaphragm.

To confirm that the panel is arcing, you might try I removing the outer fabric dust cover and playing the speaker in a darkened room. In the dark, you should be able to visibly see any arcing and locate the burn thru, if that in fact is the issue.

There's a company in Australia that may have a rebuild kit; although I can't recall the company name (senior moment). And there's a very sharp guy here in the states named Sheldon Stokes that rebuilds ESL 57's -- maybe 63's too. You can find Sheldon's website by Googling his name.

jaywills · « **Reply #66 on:** 10 Dec 2018, 12:11 pm »

I have a pair of 63's and Jazzman has diagnosed your problem correctly in my experience. My burn came from an overly enthusiastic, alcohol assisted listening session.

Try running them in the dark without socks to confirm. Mine looked like a miniature thunderstorm. Panel will need rebuilding/replacing. Mine was done ~ 10 years ago. If I can find the fellow (in Florida, IIRC), I'll pm the contact info (no affiliation other than being satisfied customer). Ran around $300, IIRC. Good luck.

Mr. Big · « **Reply #67 on:** 29 Mar 2023, 09:52 pm »

Cannot go wrong with Kent and Electrostatic Solutions, for repairs and total rebuilds. He is the best one and is located in KC so good for shipping them to him no matter where you live.