Text just a few posts back by Sheldon: "Quad LOVED (and I mean loved) thermoset glues, they are all over all the quad speaker designs".wtf they hotsnot them ? i know they prob used the hotsnot for fabricit comes in really nice woven mesh. but i wonder how this holds and what happens to the resonance. its is not how it was done before
How do you know your's are originals and not already re-applied? Did you buy them new? How many "originals" survive these days? Very little I guess.
Other question: How would they use hot melt on the mesh? It would clutter up all the tiny openings!
If the 63's are perfect, why then did they introduce the 989 with extra panels and are now bringing out an 8 panel ESL ?
My subs are open baffle (dipole) to mirror the Quads and are DSP controlled.
I can switch them on/off from my laptop so it is easy to see whether filling in the bottom Octave is beneficial or detrimental.
All things being equal, the rather suppressed top two octaves will make the Quad sound somewhat mellow, The speaker becomes very directional above 8kHz or so, which will exacerbate the rolled-off top octave in medium to large rooms.
Read more at Quad ESL-2912 loudspeaker Measurements | Stereophile.com
I use Adam Air Motion Transformers for the top Octave (supertweeter) these are positioned in the centre of the delay rings.
Sounds familiar ? these are as fast and distortion free as the Quads IMO.
ADAM Audio - The X-ART Tweeter
Last edited:
This is quickly devolving into a quad discussion, and is pretty far off topic. I'm sorry to readers about that, but I'm going to continue to go off topic, so feel free to flame me mercilessly.
Thermoset glues in quads: Until late in the 2805 production, the diaphragms were held in place with thermoset glue. The easiest way to remove a diaphragm is to use a heat gun and soften the glue. Likewise the stators are held to the nylon frame with thermoset glue as well, but that glue turns to powder over time (thank you quad for all the business). A little heat,(like just a whiff of the heat gun) and the stators come free of the support structure.
The newest panels have changed glues (thanks for that, it's only been thirty years) and hopefully stator de-lamination is a thing of the past. But now there is a diaphragm rot, where the diaphragms split in lots of little places and ultimately split.
Quads and Subs and SuperTweeters: That's not my cup of tea, I like simplicity. But lots of people use subs with the quads, and with the right crossover and a low crossover point, it can be a reasonable thing to do if you NEED the bottom octave (I don't; it just angers my wife). The nice part is the wavelengths down low are really long, and it's easy to make it phase coherent. I have never played with a super-tweeter because I've never felt that I needed one. I suspect that it would be tricky to integrate into the quads and maintain phase coherency due to such short wavelengths.
ESL-63's vs larger Quad ESL's: I am a big fan of the 63's, the size of them is really optimum for sound reproduction (if you are not obsessed with the bottom octave) and living with them in a way that doesn't take over the living space. I own a set of 2912's (as I said earlier in the thread), and while they offer more presence and a bit more bass authority, they are really quite imposing, especially in a smaller room. Also it appears that quad did effectively nothing but tack on the extra two panels, with no changes to the crossover circuit. The one thing that the 6 panel models offer is enough bass output to make me not consider a subwoofer with any type of music.
However, super-tweeter or sub or whatever, audio is about music enjoyment. And if some folks love the sound of the quads with extra do-dads tacked on (there's a ton of stacked quad HQD maniacs out there too), I'm all for it.
A lot of folks don't find the quads to be their cup of tea and that's fine with me too (I call those folks "deaf people"), it's all about enjoying the music.
Sheldon
quadesl.com
Thermoset glues in quads: Until late in the 2805 production, the diaphragms were held in place with thermoset glue. The easiest way to remove a diaphragm is to use a heat gun and soften the glue. Likewise the stators are held to the nylon frame with thermoset glue as well, but that glue turns to powder over time (thank you quad for all the business). A little heat,(like just a whiff of the heat gun) and the stators come free of the support structure.
The newest panels have changed glues (thanks for that, it's only been thirty years) and hopefully stator de-lamination is a thing of the past. But now there is a diaphragm rot, where the diaphragms split in lots of little places and ultimately split.
Quads and Subs and SuperTweeters: That's not my cup of tea, I like simplicity. But lots of people use subs with the quads, and with the right crossover and a low crossover point, it can be a reasonable thing to do if you NEED the bottom octave (I don't; it just angers my wife). The nice part is the wavelengths down low are really long, and it's easy to make it phase coherent. I have never played with a super-tweeter because I've never felt that I needed one. I suspect that it would be tricky to integrate into the quads and maintain phase coherency due to such short wavelengths.
ESL-63's vs larger Quad ESL's: I am a big fan of the 63's, the size of them is really optimum for sound reproduction (if you are not obsessed with the bottom octave) and living with them in a way that doesn't take over the living space. I own a set of 2912's (as I said earlier in the thread), and while they offer more presence and a bit more bass authority, they are really quite imposing, especially in a smaller room. Also it appears that quad did effectively nothing but tack on the extra two panels, with no changes to the crossover circuit. The one thing that the 6 panel models offer is enough bass output to make me not consider a subwoofer with any type of music.
However, super-tweeter or sub or whatever, audio is about music enjoyment. And if some folks love the sound of the quads with extra do-dads tacked on (there's a ton of stacked quad HQD maniacs out there too), I'm all for it.
A lot of folks don't find the quads to be their cup of tea and that's fine with me too (I call those folks "deaf people"), it's all about enjoying the music.
Sheldon
quadesl.com
Are you sure the higher humidity isn't just increasing the removal of charge from the diaphragms and not really changing the coating at all?
That blinking rate seems perfectly acceptable to me. You'll also notice that the blinking rate will increase a lot with a musical signal.
For anybody who is interested, the blink rate can be used to determine the leakage current as follows:
Current vs blink rate for ESL63’s:
Q = C * V
Q = 47e-9 * 90
1A = 1Q/sec
Rate = 4.23e-6 amps / 1 sec blink
(I'm assuming the Neon turns on at 90VDC)
Sheldon
well love the explanation but i think you are wrong .one of the things about most thermo setting glue is that they remain rather thick. i dont even see a glue layer in my old quads and they rip like polyurethane. like rather good sideways grip but hardly any in the upward direction.
( Likewise the stators are held to the nylon frame with thermoset glue as well, but that glue turns to powder over time (thank you quad for all the business)[QUOTE/]
i am rather sure quad did not wast money on getting there frames made out of nylon.
nylon frames would be a ******* bitch to glue anything to as well as it is conductive depending on humidity. so no!!!!! just feel anything nylon and you know straight away it is not nylon!
Last edited:
well love the explanation but i think you are wrong .one of the things about most thermo setting glue is that they remain rather thick. i dont even see a glue layer in my old quads and they rip like polyurethane. like rather good sideways grip but hardly any in the upward direction.
How many have you seen to make such a blunt statement?( Likewise the stators are held to the nylon frame with thermoset glue as well, but that glue turns to powder over time (thank you quad for all the business)[QUOTE/]
i am rather sure quad did not wast money on getting there frames made out of nylon.
nylon frames would be a ******* bitch to glue anything to as well as it is conductive depending on humidity. so no!!!!! just feel anything nylon and you know straight away it is not nylon!
I have seen only about 80-100 frames the recent years, so certainly not as many as a professional ESL repair guy would have, and yes quite a few of my examples had melt glue both for the stator and the Mylar. I also guess that not many of the lot were originals that weren't tempered with. Most of the ESL's have been repaired one way or another over the last decades.
Agree on the nylon. The white frames are probably ABS. Cheap? Maybe, but also very durable, light, form retaining and it is and isolator, so why call it c***p? You're not a fan that's obvious, but using these words doesn't help.
Put the whole concept and it's quality in the period, the sixties-eighties. Always easy to look back and point at what was wrong. But it had to be mass produced and affordable for the general public. It's not a million dollar / pound / euro speaker. Luckily that was one of the major goals that Peter Walker had when developing the ESL's. That came with compromises and challenges that had to be met.
Granted that I'm very partisan towards Dayton-Wright equipment. But early Quad speakers always looked to me as if they were made by some kids in their parents' garage. Dayton-Wright gear, by stark contrast, always looks "MIL-SPEC" (military grade).
Mockery aside, below is a picture of the type of cell D-W used. It is cast plastic of some kind quite rigid, deep ribs. The stator is formed by spraying conductive paint to the inner face. There are cavities at both ends that hold 25-megOhm (?) resistors.
I couldn't say what structural differences matter. Just illustrating difference in construction.
BTW, based on the D-W example I've often though that DIY ESL panels might be built with egg-crate "lenses" from ceiling fluorescent luminaries.
B.
Mockery aside, below is a picture of the type of cell D-W used. It is cast plastic of some kind quite rigid, deep ribs. The stator is formed by spraying conductive paint to the inner face. There are cavities at both ends that hold 25-megOhm (?) resistors.
I couldn't say what structural differences matter. Just illustrating difference in construction.
BTW, based on the D-W example I've often though that DIY ESL panels might be built with egg-crate "lenses" from ceiling fluorescent luminaries.
B.
Attachments
Granted that I'm very partisan towards Dayton-Wright equipment. But early Quad speakers always looked to me as if they were made by some kids in their parents' garage. Dayton-Wright gear, by stark contrast, always looks "MIL-SPEC" (military grade).
are you sure you talk about quad. you mean like 57 that might even won a few design awards and might win them on this current day as well if they would re- release them
I agree 100% about the original quads looking like they are a science fair project. There is a good changes of getting cut or splinters when picking them up by the bottom too. No fuse in the power supply either. The back grille cutouts for the power supply and input are never in the right position. I can't believe that they sell for as much as they do.
I'm speaking from ignorance, but needing their own internal atmosphere to operate correctly isn't really such a great design for a home speaker either. Not that I have any grounds to talk since I fix quads, but those D-W molded parts also look a bit cheesy.
These are all crappy consumer goods, so it doesn't surprise me that they have issues.
Partly on-topic
The gas atmosphere concept provides monumental sound benefits (particularly by lowering the low freq horizon) along with some acoustic problems. Not to mention the expense of building such a speaker and maintenance issues and climate change (greenhouse gas).
But, it allows greatly increased bias voltage, which has consequences for the diaphragm coating, drive voltage, and because of increased efficiency, the demands on the amp.
B.
Last edited:
Do you refer to to the ESL 60S that was presented at Munich in may 2017? I don't think it's an 8 panel system. But I wasn't there so I might be wrong. Looks like a 6 panel system with the panels rotated 90 degrees. Look at the width in resemblance to the 2912. Will it ever be produced? After Munich I haven't seen or heard anything about it from Quad.
It appears that the stator to frame glue was changed late in the 2805 run. But all the Chinese made quads also suffer from diaphragm rot. My 2912's had 5 panels die in 4 years. So the stator glue isn't the only problem they have.
Sheldon
quadesl.com
What is the diaphragm rot ? never seen one or i dont know what i am looking for maybe
Though you have to factor in the time constant. .1957. . (Before I was born - just)
Few homes had central heating, you had to light a coal fire and wait for it to heat the room.
Consequently humidity levels would have been far higher, I believe Quad took this into account with their resistive coating and actually recommended an in room humidity level of 40-90 % for correct operation.
This reflected the times.
They only sold them. one .at a time, as Stereo, like central heating and air conditioning were things for the future..
Here is a car from 1957.
Would you use this as a daily run around now ? With drum brakes all around no power steering or servo assisted brakes.
I think we sometimes take for granted what we have, if you mentioned 'stereo' in 1957 people would think you were nuts..
Last edited:
I doubt he's trying to impress anyone, just share how he has approached getting them to sound the way he wants. Given that he's using dsp and powerful amps to drive his subs I think it's far to assume the acoustic match is very good. After all there's no deep instruments producing square waves at 20hz so i imagine his subs are more than capable of timing correctly, the same goes for his ribbon tweeters which are placed at the centre of the treble panels retaining the coincident source for those frequencies which are directional.
Though you have to factor in the time constant. .1957. . (Before I was born - just)
Few homes had central heating, you had to light a coal fire and wait for it to heat the room.
Consequently humidity levels would have been far higher, I believe Quad took this into account with their resistive coating and actually recommended an in room humidity level of 40-90 % for correct operation.
This reflected the times.
They only sold them. one .at a time, as Stereo, like central heating and air conditioning were things for the future..
Here is a car from 1957.
Would you use this as a daily run around now ? With drum brakes all around no power steering or servo assisted brakes.
I think we sometimes take for granted what we have, if you mentioned 'stereo' in 1957 people would think you were nuts..
That ain't just any old car... that's a 57' Nomad. It's worth a small fortune today. I had a 56' Nomad when I was a teenager and I made the mistake of leaving it parked in my I mom's back yard with a blown engine (for several months) and she had it towed away. I tracked it down to a local junkyard and they had already crushed it into a little box. Now, you would think that anyone working in a junkyard in the early 70's would know the value of a 56 Nomad, and not crush it... but NO... there are idiots everywhere (especially me for leaving it in mom's yard for months on end).