I've replaced both EHT boards on my ratty ESL 57s, and now both treble panels have a delightful fuzzy noise and a bit of arcing... I completely stripped one of them and put new dust covers on bass panels, but didn't touch the treble. In the second one I just popped in the new OTA EHT board without touching anything else. My question is - were the treble panels likely dodgy before I started, but because of the old EHT boards this didn't reveal itself until I put the new parts in? Or have I just somehow damaged the treble panels in the process?
Well, you shouldn't have any noise from them for sure. The prevailing wisdom is that the treble panels are the ones that get damaged by being overdriven, while this rarely enough hits the bass panels. On the other hand, it seems the dustcovers on the bass panels tend to need replacement more than the treble panels.
not being insulting but are you sure you connected the HT back up the right way around? The treble panels get 1.5kv, and the 6kv goes to the bass panels and not the other way round....
not being insulting but are you sure you connected the HT back up the right way around? The treble panels get 1.5kv, and the 6kv goes to the bass panels and not the other way round....
Paul R
pfm Member
Two sources of arcing in an ELS, between the stators, driven by the amplifier, this is bad as there is lots of power available. On the Quad this is really a treble only issue since the conductive surfaces on the tweeter are on the inside of the panel, and the stators are close. The bass units have the conductive surfaces on the outsides of the conductive panels and the panels are more widely separated. So an arc has to travel through the perforation, across the gap and through the other perforation. I think this is very unusual. You can drive the diaphragm into the panel with no damage. If this happens in the treble you probably blow a hole in the diaphragm and that's game over. The other source of arcs is EHT leaking. This is unlikely to cause damage since there is no power behind it, it's more in the nature of a static discharge.
As fran suggests, are you sure you connected the new EHT up correctly? There should be two outputs, one for the tweeter, and one for the bass panels. The former is probably nearer the input than the latter since it involves fewer stages of voltage doubling. Post a photo if in doubt.
As fran suggests, are you sure you connected the new EHT up correctly? There should be two outputs, one for the tweeter, and one for the bass panels. The former is probably nearer the input than the latter since it involves fewer stages of voltage doubling. Post a photo if in doubt.
I see there's a pair of 2805s on eBay for £1400. If I had the space I'd snap them up. My last house had a larger lounge that could just about accommodate ESLs, though they dominated the space. I trialled a pair of demo 2805s at home and they made the best sounding hifi I've ever had. In the end I opted for a pair of B&W 803D2s, a BIG mistake as the treble was so exaggerated it practically lacerated my ear drums. I've ended up with a pair of Harbeth M30.1s, which are very good in many respects but flawed in others. If I move to a large enough house, the Quads will be on the hit list.
And we have a winner! Fran, you were right! The photo on the EHT board eBay ad has the labels for the bass and treble wires the wrong way round!! You've just saved me £280 and a lot of faffing about, thanks so much!
tonerei
pfm Member
Yes a great result. Fran has a knack of resolving these issues ( I have plenty of experience in that area where Fran has saved the day and the money 
)
But it is not all positive. I am currently enjoying 'stacked' (Side by side) 63's because of Fran's experiments and in my room which is approx 15x15x10 (Feet) sound incredible.
Like Fran I am surprised many more haven't tried this out. The level and depth of detail is just unreal to my ears anyway. Huge soundstage and added body and hugely coherent. It is in no way disjointed. Highly recommend to people especially UK folk as it is a fairly cheap experiment to nirvana. Minus the look in the room!
Found this nice review of 57 and 63's yesterday.
)But it is not all positive. I am currently enjoying 'stacked' (Side by side) 63's because of Fran's experiments and in my room which is approx 15x15x10 (Feet) sound incredible.
Like Fran I am surprised many more haven't tried this out. The level and depth of detail is just unreal to my ears anyway. Huge soundstage and added body and hugely coherent. It is in no way disjointed. Highly recommend to people especially UK folk as it is a fairly cheap experiment to nirvana. Minus the look in the room!
Found this nice review of 57 and 63's yesterday.
herb
brain's right hemisphere
Yes a great result. Fran has a knack of resolving these issues ( I have plenty of experience in that area where Fran has saved the day and the money
But it is not all positive. I am currently enjoying 'stacked' (Side by side) 63's because of Fran's experiments and in my room which is approx 15x15x10 (Feet) sound incredible.
Like Fran I am surprised many more haven't tried this out. The level and depth of detail is just unreal to my ears anyway. Huge soundstage and added body and hugely coherent. It is in no way disjointed. Highly recommend to people especially UK folk as it is a fairly cheap experiment to nirvana. Minus the look in the room!
Found this nice review of 57 and 63's yesterday.
Comparing them on a laptop through Grado LS1s.
Wow I heard echoes of my ESL 57s new in 1974 for 14 years. They had to go through room issues after that. The differences between the speakers were rather obvious. I prefer my Harbeths with classical music to the 63s. The 57s showed up the nonsense which was digital music in the early eighties. Just sayin'
Sorry to be nosey but I am really intrigued by your reference to side by side “stacked 63s”. Is this like a fan of 63s in front of the listening position? If so how are they connected to an amplifier? Is there a daisy-chaining or similar?
I use 63s at home with a Neurochrome amp.
I use 63s at home with a Neurochrome amp.
Yes a great result. Fran has a knack of resolving these issues ( I have plenty of experience in that area where Fran has saved the day and the money
But it is not all positive. I am currently enjoying 'stacked' (Side by side) 63's because of Fran's experiments and in my room which is approx 15x15x10 (Feet) sound incredible.
Like Fran I am surprised many more haven't tried this out. The level and depth of detail is just unreal to my ears anyway. Huge soundstage and added body and hugely coherent. It is in no way disjointed. Highly recommend to people especially UK folk as it is a fairly cheap experiment to nirvana. Minus the look in the room!
Found this nice review of 57 and 63's yesterday.
misterdog
Not the canine kind
Although the ESL-63 (and, before it, the ESL) had been well received by audiophiles, many felt it could be improved by judicious modifications. The easiest and simplest modification involved stands that elevated the speaker and stiffened its frame, the best known of which was the Arcici stand (footnote 2). (Sadly, Arcici and its founder, Ray Shab, are no longer with us.) Removing or lowering the speaker's cloth "sock" has been widely regarded as effective in improving its transparency—and producing a singularly ugly loudspeaker. The most radical modification of the ESL-63—by Alistair Robertson-Aikman, founder of SME—was described in Ken Kessler's excellent book, Quad: The Closest Approach. The mod dispensed with the sock, metal grille, and Mylar dustcover, without which—as Robertson-Aikman warns in the chapter he wrote for Kessler's book—"there is high risk of electric shock which can continue for some time after the unit is switched off." The structural modifications included transverse brass beams weighing some 70 lbs and a metal frame, the effective weight of the entire assembly further increased by a 100-lb billet of steel attached to the top of each speaker. Elements of the Robertson-Aikman mod can be seen in the current ESL-2912 ($13,999/pair).
https://www.stereophile.com/content/quad-esl-2912-loudspeaker
Perhaps the all time record holder in the Quad Stacking field was Alistair Robertson-Aikman, the owner of SME. He had a stacked pair in each corner of his (massive) listening room. It is rumoured that he also experimented with up to 16 of the speakers arranged in an arc across the sound stage - money no object!
http://www.quadesl.org/index.php/hard-core/stacked-quads
https://www.stereophile.com/content/quad-esl-2912-loudspeaker
Perhaps the all time record holder in the Quad Stacking field was Alistair Robertson-Aikman, the owner of SME. He had a stacked pair in each corner of his (massive) listening room. It is rumoured that he also experimented with up to 16 of the speakers arranged in an arc across the sound stage - money no object!
http://www.quadesl.org/index.php/hard-core/stacked-quads
tonerei
pfm Member
No bother at all, they are side by side with the outside one turned in. Sweet spot is narrow aka 57's. You can just experiment with various positions till you are happy. Both sets raised using stand and deliver stands and a platform and a timber wine box to bring the second pair to the same height. Wiring is in parallel. Two sets of speaker cables on each side. So wire up the speakers as you normally would you just have an extra pair of connections at the amp end. You could also loop on from one speaker to the other. My amp is a Jadis DA88S and I am using a CJ preamp.
As I said Fran experimented with this and I heard the results in his place. Whilst I wanted to ignore it as my room is just not as easy to fit two pairs into, I had to give it a go since I currently own two pairs. One pair are OTA done about 4 months ago and the second pair were completely refurbed circa 10yrs ago.
When you're doing this, its important that the speakers are at the same height (and yes, getting them 10-15" off the ground helps a lot). They are just wired in parallel, and I suppose some amps might not like that, but none of mine had an issue. As Tonerei said, stacking (well, siding really?) the 63s means that they will go a little louder for the same amp volume setting, but if you level for that difference, what you get is much more impact and heft without losing the soundstage and high frequency sweetness. I really can't quite understand why more people haven't done this.
If you and a friend have a pair of 63s, you owe it to yourselves to try this out. They aren't going to be room friendly, but you probably too worried about that if you have quads already!
BTW - on the socks/dustcovers..... definitely removing the socks, grilles and dustcovers opens up the sound. Ugly as hell though and you don't want to be sticking fingers in there, or have pets/kids. There is a material called "powermesh" that a lot of fabric shops will have that makes a very good sock. Its available in a good range of colours, and gives quite good protection against dust while being acoustically neutral. Its not opaque though, so you will still see the panels through it although it masks them quite a bit. Its quite stretchy, so I left mine extra long and covered the stands I used as well.
If you and a friend have a pair of 63s, you owe it to yourselves to try this out. They aren't going to be room friendly, but you probably too worried about that if you have quads already!
BTW - on the socks/dustcovers..... definitely removing the socks, grilles and dustcovers opens up the sound. Ugly as hell though and you don't want to be sticking fingers in there, or have pets/kids. There is a material called "powermesh" that a lot of fabric shops will have that makes a very good sock. Its available in a good range of colours, and gives quite good protection against dust while being acoustically neutral. Its not opaque though, so you will still see the panels through it although it masks them quite a bit. Its quite stretchy, so I left mine extra long and covered the stands I used as well.
misterdog
Not the canine kind
Removing all the panels from the flimsy aluminium angle and frame, then fitting them into a box steel frame makes a huge difference, As Alistair Robertson-Aikman with his brass and steel billets.
I made some steel frames to hold a sock for aesthetic reasons, they can be lifted off as they are only held on with Neodymium magnets.
When Quad 'stretched' the 63's to create the 989's they merely extended the length of the 10x10 aluminium angle, making it even more flimsy.
Same with the dust cover, allowing it to flap like a sail when/if it looses tension.
I made some steel frames to hold a sock for aesthetic reasons, they can be lifted off as they are only held on with Neodymium magnets.
When Quad 'stretched' the 63's to create the 989's they merely extended the length of the 10x10 aluminium angle, making it even more flimsy.
Same with the dust cover, allowing it to flap like a sail when/if it looses tension.
tonerei
pfm Member
I have come across photo's buried somewhere on PFM of yours. They look great. No doubt your mods will yield good results but probably not for the faint hearted or most folk who want to just buy and listen
. In my set up the OTA pair with their more open grills sound very transparent to me. It could be my ears but I don't notice any huge improvement running those 63's naked. My room is well damped and I have a hotchpotch of bass traps and acoustic panels unscientifically placed in the room. 989's would be more acceptable in my room space. I saw a pair that went for £1250 on ebay with all panels done by Quad about 18months ago. Timing and the location in the UK prevented me pursuing them. When he reduced the price they sold within a day.I think if I was to ever pursue your ideal I would still want dust covers and some form of protection. I could see deeper frames in timber or steel providing a bit more comfort or maybe using the OTA grilles.
Thanks for pointing out the size of the dust cover on the 989's. I had wondered if they had divided it in two which would be sensible but the sail analogy I could visualize as very true.
Thanks for the extra advice.
At the risk of making a fool of myself I’ll admit to having often wondered whether using 2 pairs of 63s opens up the opportunity to use one pair as (modest) subwoofers for the primary pair. By that I mean having some kind of simplified filter that directed the music output above a certain frequency to the primary pair and all the lowest frequencies to the second pair. At this point I have to stress I have ZERO technical background/understanding and therefore I am very likely to be describing something unbelievably stupid. However it occurred to me that doing this would relieve the primary pair of 63s from the “stress” of dealing with the lowest frequencies and the second pair acting as (modest) subs would at least have the matching fast bass that I have seen other people citing as a problem in matching traditional moving coil subs to ESLs. Equally I would have thought that the crossover between the 2 sets of quads could be much simpler than a typical unit for subs. Against that, I imagine that the crossover would have to sit ahead of the power amps so a second power amp would be also needed.
What am I missing in theory? Please be gentle!
At the risk of making a fool of myself I’ll admit to having often wondered whether using 2 pairs of 63s opens up the opportunity to use one pair as (modest) subwoofers for the primary pair. By that I mean having some kind of simplified filter that directed the music output above a certain frequency to the primary pair and all the lowest frequencies to the second pair. At this point I have to stress I have ZERO technical background/understanding and therefore I am very likely to be describing something unbelievably stupid. However it occurred to me that doing this would relieve the primary pair of 63s from the “stress” of dealing with the lowest frequencies and the second pair acting as (modest) subs would at least have the matching fast bass that I have seen other people citing as a problem in matching traditional moving coil subs to ESLs. Equally I would have thought that the crossover between the 2 sets of quads could be much simpler than a typical unit for subs. Against that, I imagine that the crossover would have to sit ahead of the power amps so a second power amp would be also needed.
What am I missing in theory? Please be gentle!
misterdog
Not the canine kind
Internet nonsense, though with my 989's they dig lower to start with.
I do feed the Quads full program though and use separate amplification and DSP for the subs.