enilsen
Well-known member
I own a pair of CLS's that were weak in sound on the one panel and mine are from the mid 80's production numbers #441/442. This might or might not apply to other owners, but after doing the vacuum and shower procedure my speakers did return to normal operation again. At least for a couple of days.
My assumption at first was years of grime that had built up on the membrane was draining the static charge from it and the thorough cleaning with warm water might removed this kind of obstacle restoring them to near factory condition. No one has stated yet that the static charge is the culprit in question so maybe there was a physical failure here instead.
I then e-mailed ML to see if they had any other solutions to my problem and was told that the panels needed replacing due to the fact that the conductive coating was failing. Other posts report the same answer as I got from ML.
I was however not quite satisfied with this response as there was a significant replacement cost involved and my personal attempt that almost worked in restoring the sound to my vintage CLS's. I figure that I had nothing to loose by experimenting with the cleaning process in question and trying to understand why showering the panels temporary restored the sound.
After several showers later with the same positive results I got tired of doing this extreme man handling of my speakers and resorted to using a small plant sprayer filled with water. I soon discovered that doing a very small squirt to the lower left side and lower center portion of the panel yielded the same positive results. This spraying process is done while the speakers are “ON” and music playing at low volume. Needless to say that this does appear to be a dangerous task at hand and the threat of electrocution a very real possibility, but I am writing this as a testimony to surviving the ordeal and can sincerely conclude that ML have done a brilliant job with insulating those high voltage stators.
Unfortunately using the plant sprayer filled with water is only a temporary solution to this problem and I can only speculate that it is restoring the electrical connection between the bias aluminum strip at the base of the conductive membrane. Eventually the water evaporates and the restored connection is lost to resume where we started from when the sound was weak (This is only my theory and others please comment if you have any other ideas).
I have since improved on this process and after a lot of research and experimentation found that using a diluted solution of water and “ANTIBACTERIAL LIQUID SOAP” instead of regular tap water has resulted in a more permanent connection between the bias aluminum strip and the conductive membrane. It has worked for over 15 months now after a single application and I can not hear any deterioration of the sound yet. The sound is evenly projected from the whole panel and efficiency has improved dramatically. I welcome any comments on this if anyone has a better solution to the problem other than replacing the panels or using just the shower and hair drier to re-establish near factory sound.
Hope this might be a useful fix when all else fails. There is no guaranty that this will work for all CLS speakers as through the years ML has obviously been aware of the problem and made changes to address these kinds of issues. Hence the option to purchase new panels.
The product I used is called “TERSASEPTIC” purchased in a Canadian pharmacy, but I’m sure other liquid soaps with similar conductive properties would also work.
The idea of attempting to repair the panels using liquid soap comes from other sites where owners have restored the conductive coating on Quad electrostatic speakers by applying either graphite powder or liquid soap. For some odd reason conductive coatings are well kept secrets so no one has pointed me in the direction of what brand names would be suitable.
Note. Applying this solution would be best achieved by using a small eye dropper or a thin tube along the lower part of the perforated stator. Allow only a small amount of liquid to run down the membrane (not the stator!) and meet the soft insulating rubber strip. Continue at even spaces about 1" apart until you cover the width of the speaker.
My assumption at first was years of grime that had built up on the membrane was draining the static charge from it and the thorough cleaning with warm water might removed this kind of obstacle restoring them to near factory condition. No one has stated yet that the static charge is the culprit in question so maybe there was a physical failure here instead.
I then e-mailed ML to see if they had any other solutions to my problem and was told that the panels needed replacing due to the fact that the conductive coating was failing. Other posts report the same answer as I got from ML.
I was however not quite satisfied with this response as there was a significant replacement cost involved and my personal attempt that almost worked in restoring the sound to my vintage CLS's. I figure that I had nothing to loose by experimenting with the cleaning process in question and trying to understand why showering the panels temporary restored the sound.
After several showers later with the same positive results I got tired of doing this extreme man handling of my speakers and resorted to using a small plant sprayer filled with water. I soon discovered that doing a very small squirt to the lower left side and lower center portion of the panel yielded the same positive results. This spraying process is done while the speakers are “ON” and music playing at low volume. Needless to say that this does appear to be a dangerous task at hand and the threat of electrocution a very real possibility, but I am writing this as a testimony to surviving the ordeal and can sincerely conclude that ML have done a brilliant job with insulating those high voltage stators.
Unfortunately using the plant sprayer filled with water is only a temporary solution to this problem and I can only speculate that it is restoring the electrical connection between the bias aluminum strip at the base of the conductive membrane. Eventually the water evaporates and the restored connection is lost to resume where we started from when the sound was weak (This is only my theory and others please comment if you have any other ideas).
I have since improved on this process and after a lot of research and experimentation found that using a diluted solution of water and “ANTIBACTERIAL LIQUID SOAP” instead of regular tap water has resulted in a more permanent connection between the bias aluminum strip and the conductive membrane. It has worked for over 15 months now after a single application and I can not hear any deterioration of the sound yet. The sound is evenly projected from the whole panel and efficiency has improved dramatically. I welcome any comments on this if anyone has a better solution to the problem other than replacing the panels or using just the shower and hair drier to re-establish near factory sound.
Hope this might be a useful fix when all else fails. There is no guaranty that this will work for all CLS speakers as through the years ML has obviously been aware of the problem and made changes to address these kinds of issues. Hence the option to purchase new panels.
The product I used is called “TERSASEPTIC” purchased in a Canadian pharmacy, but I’m sure other liquid soaps with similar conductive properties would also work.
The idea of attempting to repair the panels using liquid soap comes from other sites where owners have restored the conductive coating on Quad electrostatic speakers by applying either graphite powder or liquid soap. For some odd reason conductive coatings are well kept secrets so no one has pointed me in the direction of what brand names would be suitable.
Note. Applying this solution would be best achieved by using a small eye dropper or a thin tube along the lower part of the perforated stator. Allow only a small amount of liquid to run down the membrane (not the stator!) and meet the soft insulating rubber strip. Continue at even spaces about 1" apart until you cover the width of the speaker.
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