Is it safe to use a compressed air duster on my panels?

[Jules_S]

Hi all

As-per the thread title really. I'm noticing what I can only describe as like a breakup distortion on female vocals and similar-pitched instruments, with my early Summits. It's not terrible, but it is definitely noticeable. I do vacuum the panels from time to time but I wonder if I'm not getting it all off (I usually end up doing it after they've been recently used because I forget to turn them off and leave them to discharge)

I wondered about using one of these compressed air canisters to aim more directly between the holes in the stators to see if I can dislodge any more dust perhaps? Yeah I know it will take ages. I think the diaphragms are meant to be pretty robust. Has anyone else tried this and did it help? I'm wondering if it's just an accumulation that's creating this sound or if the panels themselves could be on the way out. I used the rest of my system (amp & SACDP) at a friend's house over the weekend so I know there's no issues there. Speakers are from 2005 - I was informed by the seller 18 months ago that they had been "serviced" (most likely just inspected) by the UK distributor Absolute Sounds and got a clean bill of health.

 

[Rascal]

Hi. Here's some advice I received from Martin Logan support a while ago when one of my panels lost output and sounded muffled. I've reported it elsewhere. I have Montis, which is just one generation newer than the Summits. Here goes:

To get rid of the dust from the ESL panels -- soft vacuum or high-pressure (which I'm not sure is such a good idea -- more on this soon) -- you MUST discharge the particles or else the dust just won't leave the membrane surfaces. Unplug the speakers, disconnect the speaker wires, and leave the the ESLs alone. ML support called for at least 4 hours, but my experience is a good solid 24 hours. After that, a good vacuum (I use a tank-type Dyson with the upholstery attachment) will readily remove the dust that remains. Vacuuming has been so effective for me I just don't think a a powerful air hose (such is used to clear drum brakes) is really necessary. And, while fairly durable (according to Service), the membrane is thin and not certainly not built like a brake drum.

So, in summary, the key is to discharge the panels thoroughly before trying to get rid of the dust.

Once the panels are vacuumed, reattach the speaker wires and the power cord, and off you go.

Just my two cents.

 

[twich54]

furthering what Rascal said, back when I had my Logans my preferred way to vacuum was with the use of a horse hair brush attachment for it did not promote static electricity like a synthetic bristled brush would yet still got in the perfs.

Also, I was fortunate to have a limited dusty environment

 

[rpokuls]

I would leave the speakers unplugged for longer than 24 hours.

A while back, I unplugged the speakers and then after 24 hours, proceeded to vacuum them. I forgot
to plug them in again. Was surprised that when I started to play music, you could clearly hear music
coming from the panels which must mean that there still was some residual static charge on the panel.

The volume was of course nowhere near normal, but still there.

 

[sgordon10]

Another issue with forced air...
where will the dust settle?

 

[Jules_S]

I had thought of taking them outside to blow the dust off, but point taken if doing it indoors.

Speakers have been switched off for around 18 hours now so hopefully by the weekend I should be able to give them a good vacuum. Hoping that doing that is enough to restore some clarity, if not then I guess it may be time to think the unthinkable, and replace the panels...

 

[sleepysurf]

I would leave the speakers unplugged for longer than 24 hours.

A while back, I unplugged the speakers and then after 24 hours, proceeded to vacuum them. I forgot
to plug them in again. Was surprised that when I started to play music, you could clearly hear music
coming from the panels which must mean that there still was some residual static charge on the panel.

The volume was of course nowhere near normal, but still there.

After unplugging for 24 hrs, you can quickly dissipate any residual charge by playing music until they are silent, then clean them.

 

[Russr]

I had thought of taking them outside to blow the dust off, but point taken if doing it indoors.

Speakers have been switched off for around 18 hours now so hopefully by the weekend I should be able to give them a good vacuum. Hoping that doing that is enough to restore some clarity, if not then I guess it may be time to think the unthinkable, and replace the panels...

Yeah, no, I don't think outside is a great idea... the vortices formed by the compressed air streams/blasts would bring all kinds of objects into contact with the membranes... at least indoors is somewhat filtered.

And in this context, always better to suck than blow...

 

[Rascal]

it’s not clear taking the ESLs outdoors is really necessary or even an advantage.

it’s not clear to me that playing music through an unpowered ESL dispels charge. It could in fact charge the membrane and dust particles instead. By disconnect I meant no power and no speaker connections (both) for 24 hours. I don’t think 4-6 hours (Service suggestion) is enough (not according to my experience). Longer than 24 hours can’t hurt.

My suggestions have come from exchanges with Martin Logan Service. Contacting them has been productive and is highly recommended. I would especially consult with them before contemplating disassembly or panel replacement.

 

[Robert D]

Yeah, no, I don't think outside is a great idea... the vortices formed by the compressed air streams/blasts would bring all kinds of objects into contact with the membranes... at least indoors is somewhat filtered.

And in this context, always better to suck than blow...

Thats what she said.

 

[Russr]

Thats what she said.

THANK YOU!!! AFter lobbing one out there like that, it would've been a cryin' shame if no one converted it!

 

[sgordon10]

You may consider using a Walker Talisman or other device to demagnetize your panels, while they are unplugged. Can't hurt!

 

[rpokuls]

After unplugging for 24 hrs, you can quickly dissipate any residual charge by playing music until they are silent, then clean them.

Good idea!

 

[Leporello]

After unplugging for 24 hrs, you can quickly dissipate any residual charge by playing music until they are silent, then clean them.

Some people say this could damage the signal step-up transformers, but I don't really buy that. However to discharge the panels you can disconnect the lead to the diaphragm then short the diaphragm lead to either, or both, of the stator connections.

Also, if you hear audio even after discharging for 24 hours it doesn't necessarily mean there is significant charge, at least not enough to draw dust. The field generated by the stator input will polarize the material of the diaphragm to some extent.

It probably wouldn't hurt to use relatively low pressure compressed air, like "Dust-Off" (which at one time I used regularly to blow dust off photo negatives), perhaps simultaneously while vacuuming (so you know where the dust is going). I wouldn't be comfortable with high pressure auto service station type compressed air.

However, if you've dusted them thoroughly and you don't see dust, it's probably not the issue. The next thing to try may be shower cleaning, as is described in many postings on this forum. I would only try that as a last resort, after being almost resigned to new panels.

I've never tried shower washing, never had to. If I were to do it, I would eschew any cleaning solvents--some of which, apparently, loosen the conductive material. For that matter, I wouldn't use the shower at all. Use distilled water, and a large spray bottle. Obviously, make sure they are thoroughly dry before powering them up again.

And no, taking them outside to attempt cleaning is a bad idea. The potential exposure to dust of all kinds is much greater than inside, where even if you haven't vacuumed recently, the dust tends to settle on surfaces and stay put unless disturbed. Outdoors there's soil, pollen, gravel, seeds, etc. blowing all over the place.

 

[Mirolab]

Wow.... several people here are really afraid of the great outdoors!
I have an air compressor, and I absolutely would NOT be blowing out my panels IN the house!
I would do it on my outside patio. I HAVE done it on my patio!
About 10 years ago, my SL3's were in a hopeless state with low efficiency and rolled off highs. Vacuuming and blowing no longer helped. I had nothing left to lose, so took them apart and sprayed the panels down with the hose!
YES!! that brought them back to life.... about 75% of the way anyway. I used them for a couple more years, and finally decided to commit to new panels. Now I'm enjoying my SL3's that are possibly better than when they were new, with new panels and X-over caps.

 

[Jazzman53]

I would use vacuum-- but blowing the panels out with compressed air won't hurt them if you crank down the pressure a bit and don't place the nozzle closer than about a foot away.

I've used compressed air on to blow out speakers with 6 micron diaphragms, and ML diaphragms are twice that thickness so; no worries there.

To extend the life of the diaphragm coating, the newer MLs have a music sensor that de-energizes the bias supply whenever there is no music signal detected.

My ESLs don't have a music sensor so I have their bias supplies plugged into a switched receptacle that's only energized when the amps are on. I would do the same, even if my speakers had the sensor circuit.

Also, my speakers have acoustically transparent front & rear magnetic grills which effectively keep the dust out.

MLs don't come with grills of course, but grill cloth is cheap and it wouldn't be a bad idea to have some socks sewn up to cover the panels, at least when not in use.

 

[Leporello]

ML ESL's have had music sensors for decades. The bias supply does not shut down, though, it reduces to a standby value. Like many things, this is what ML decided is the best compromise. For best results, you should let the charge drain at least overnight before dusting, even if they've been in standby mode.

 

[Tosh]

I'm noticing what I can only describe as like a breakup distortion on female vocals and similar-pitched instruments, with my early Summits. It's not terrible, but it is definitely noticeable.

This sounds more like an ESL panel separating or cabinet structural problem than a low HV problem. All your highs are still there, from all over the panel?