Bad panel ESL X

[maverick3n1]

I bought a pair of ESL X’s from Audiogon a year ago that were supposed to be new in box. They were in perfect condition, piano black in factory packing and worked perfect. There was no question about their age.

Now however, one has a bad panel. If you hold your ear up to it and move your head from the top to the bottom, there are 3 or 4 dead spots, and if the volume is turned up fairly loud, vocals will crackle here and there.

I’ve swapped panels from one to the other to verify that it was in fact the panel, and the problem follows the panel. That’s when I found the mfg date of 2016

I’ve removed the panel from the frame and inspected it. There isn’t a scratch in the coating, no dings or warps to the panel, no tears in the material. The 3 conductors are soldered on tightly.

Unfortunately, I can’t afford to buy a replacement panel, and it’s not under warranty. Does anyone know what would cause this issue and if it’s DIY repairable?

 

[JonFo]

Now however, one has a bad panel. If you hold your ear up to it and move your head from the top to the bottom, there are 3 or 4 dead spots, and if the volume is turned up fairly loud, vocals will crackle here and there.

If it's limited to a couple of areas, and those are horizontal (go from left to right edge), then the most likely problem is that the panels have separated at these side edges. That could have happened if uneven pressure was applied during transport or if they were knocked over (falling on the panel) and the panel slightly warped and separated.

Post a pic of the sides of the panels highlighting the dead zones.

A possible fix would be to clamp those edges to ensure contact with the copper strips on the inner edges of the stators against the diaphragm. Those copper strips are how they distribute the 3Kv evenly to all areas of the diaphragm, and if an area has weak contact (or a short), then you wind up with a dead zone.

So find clamps that can apply a good amount of force, place them over the suspect areas of the edges and re-test the unmounted but clamped panel. Adjust clamps and locations until you get rid of the dead zones.

To make this permanent, glue will be involved, but that is not my area of expertise (I can glue two of my fingers together, done that), so I'll let others chime in. Paging @Brandon Hartwick

 

[maverick3n1]

So I just setup a measuring tape and went down precision listening.. it’s an obvious pattern of dead panels. I’ve marked the dead spots in the image. I think the top single section is bad as well but it’s hard to tell. If it is, that would complete the pattern.

The red spots are the dead spots. So it seems 1 good, 3 bad, 1 good, 3 bad.

 

[maverick3n1]

With this new finding, I just shot an email back to ML to see if they ever had a recall on panels for something like this. For it to be such a consistency in pattern, it makes me wonder if they had a batch where the whole roll of film had a flaw in it, which would make sense to be a consistent perfect pattern as the flaw would have likely been created by a machine, which would be repetitive in nature. To have it randomly fail in this perfect pattern just seems odd to me.

 

[maverick3n1]

With this new finding, I just shot an email back to ML to see if they ever had a recall on panels for something like this. For it to be such a consistency in pattern, it makes me wonder if they had a batch where the whole roll of film had a flaw in it, which would make sense to be a consistent perfect pattern as the flaw would have likely been created by a machine, which would be repetitive in nature. To have it randomly fail in this perfect pattern just seems odd to me.

ML said no recalls.. it’s just how the panels fail.

 

[Tosh]

A possible fix would be to clamp those edges to ensure contact with the copper strips on the inner edges of the stators against the diaphragm. Those copper strips are how they distribute the 3Kv evenly to all areas of the diaphragm, and if an area has weak contact (or a short), then you wind up with a dead zone.

I'm just emphasizing this part of the construction of the ESL sandwich. I'm guessing what's happening is the copper strip is warping and/or corroding and making poor contact to the film, so the sandwich needs pressing together somewhere along that edge.

2016 is quite young and not ready for a shower...

 

[JonFo]

The red spots are the dead spots. So it seems 1 good, 3 bad, 1 good, 3 bad.

And that's a good percentage of the total panel, but being distributed like that is interesting.

It still is most likely the diaphragm is not making good contact with the copper strips, so the clamping advice is your best bet.

 

[maverick3n1]

And that's a good percentage of the total panel, but being distributed like that is interesting.

It still is most likely the diaphragm is not making good contact with the copper strips, so the clamping advice is your best bet.

If I attempt this, is there any part of the panel I have to be careful about not touching, since I’d be testing it without it being in the frame? It’s low amperage so I’m not really so worried about being injured. More so worried about getting an unexpected shock while holding it on it’s edges and dropping the panel/possibly having it hit the piano black base unit it’s attached to and damaging it.

 

[pinoyboy]

Any updates on your esl? I have the same issue got mine 2nd hand and on of the panel has a dead spot on the bottom.

 

[Jazzman53]

If I attempt this, is there any part of the panel I have to be careful about not touching, since I’d be testing it without it being in the frame? It’s low amperage so I’m not really so worried about being injured. More so worried about getting an unexpected shock while holding it on it’s edges and dropping the panel/possibly having it hit the piano black base unit it’s attached to and damaging it.

I would advise placing some small clamps at the edge areas in question, and then NOT holding the panel while testing it-- just lay it on the floor.

If you much touch the panel while it's playing, only use one hand, so if you receive a shock, it can't travel thru your heart. The bias supply current is limited by a mega-Ohm charging resistor, so it's pretty safe. The current on the stators is not so limited and more concerning, as even a small amperage traveling thru the heart can interfere with its rhythm.

Please just clamp it and put it on the floor.

 

[Nuri58]

Maybe wear some sort of rubber gloves. That would also prevent grease from your hands to end up on the panels