There are patches of parallelogram shape and a slanted H shape adhered with the left and right sides on the inside of the backside stator of Martin Logan CLS2a. They are made of a similar material to the diaphragm. I think they are dumpers for diaphragms of bass sections. Please let me know the function and effect of those patches on the frequency responses and/or distortion? Did anybody compare the presence and absence of those patches?
Well I wish there were others that had looket at the CLS as more than a pretty face......but thay are what thay are...right
I like you have look at these tape paches inside on the back panel...
So in the pic.....we see the ML CLs panel look...never made any diff...
the one I have rework are the red ck...These had 2ea pr speaker.. 11/2" wide 36" long peace of tape on the back of the mylar it self.....
then it look like when thay moved to the one sided bass panels setup...thay moved to your type of tape peaces on the panels them selfs....
Cleaning my panels for reworking the tape came off...I thought it would...I did not think I could get it out of the panels....but I been working with ML panels before...but i was lucky....better leave it!...less it falls off..
But I new from other type ESL panels work I have done.... I could add it back if needed...more are less..on the back outside of the CLss panels there self....clear paking tape.....ML had done this them self...with the Aerius panels....that I have owned before...thay used clear plastic....tape work great an I can remove...without a trace....
Only by ear....I like it with out the tape....or you patches....but only if some one were to cross the CLs over a 80-100hz would it work....
for full rang, like I run my CLs an all other full rang type ESLs I have...
It must be there... are it well buzz an make sound ...no one could live with less it was played low....but it sounds to my ear 2-3db more output... with out the tape or patch backing....
All just one mans finding of 30 years of owning ESL speakers....My better than new..well to me...CLs are playing as I type this...there one of a kind sound an look..lot fun, great sound....after reworking these CLs panels an new interfaces bias an stepup trans...an one 1 ohm res on the input.... 60-80 tube watt well give you all the output needed...even in a big room
I like you have look at these tape paches inside on the back panel...
So in the pic.....we see the ML CLs panel look...never made any diff...
the one I have rework are the red ck...These had 2ea pr speaker.. 11/2" wide 36" long peace of tape on the back of the mylar it self.....
then it look like when thay moved to the one sided bass panels setup...thay moved to your type of tape peaces on the panels them selfs....
Cleaning my panels for reworking the tape came off...I thought it would...I did not think I could get it out of the panels....but I been working with ML panels before...but i was lucky....better leave it!...less it falls off..
But I new from other type ESL panels work I have done.... I could add it back if needed...more are less..on the back outside of the CLss panels there self....clear paking tape.....ML had done this them self...with the Aerius panels....that I have owned before...thay used clear plastic....tape work great an I can remove...without a trace....
Only by ear....I like it with out the tape....or you patches....but only if some one were to cross the CLs over a 80-100hz would it work....
for full rang, like I run my CLs an all other full rang type ESLs I have...
It must be there... are it well buzz an make sound ...no one could live with less it was played low....but it sounds to my ear 2-3db more output... with out the tape or patch backing....
All just one mans finding of 30 years of owning ESL speakers....My better than new..well to me...CLs are playing as I type this...there one of a kind sound an look..lot fun, great sound....after reworking these CLs panels an new interfaces bias an stepup trans...an one 1 ohm res on the input.... 60-80 tube watt well give you all the output needed...even in a big room
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![781488-martin-logan-cls-fullrange-electrostatic-speakers[1].jpg](/community/data/attachments/614/614467-b6c7242577416a8d130d8e47dbcfc534.jpg)
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For years I have spoke of how ML put so little bias feeding copper tape on the panels mylar.....on the 16"-12"X 46" just one side...
After reworking The ML CLS panels.....there is some thing here for a ESL panels Diyers.....
The CLS has bias feeding copper tape running ONLY....down the sides an across the bottem....NOT the top....I look at this an side it must run all the way a round for best bias feeding an to get full out put....
So I got new copper tape...an put all the way around....well,i was shocket!
I lost some of the high frec magic.....No how could this be...it work great
sounded vary good.....but...but...some thing was missing..
Could it be.... that any thing put on the mylar even on the sides ,top an bottem... after it was it was stretch tite....an ready to put the coating on would change the sound......YES....it made the mid move out more...at frist I like it....but I had to go back pull the top copper run out.....to see if I was right...that I had lost something...
An the sparkel was back....Less is more ...better image ,sweeter tone, you may think this is a little thing......IT NOT...
All just one mans finding...my reworked CSLs
After reworking The ML CLS panels.....there is some thing here for a ESL panels Diyers.....
The CLS has bias feeding copper tape running ONLY....down the sides an across the bottem....NOT the top....I look at this an side it must run all the way a round for best bias feeding an to get full out put....
So I got new copper tape...an put all the way around....well,i was shocket!
I lost some of the high frec magic.....No how could this be...it work great
sounded vary good.....but...but...some thing was missing..
Could it be.... that any thing put on the mylar even on the sides ,top an bottem... after it was it was stretch tite....an ready to put the coating on would change the sound......YES....it made the mid move out more...at frist I like it....but I had to go back pull the top copper run out.....to see if I was right...that I had lost something...
An the sparkel was back....Less is more ...better image ,sweeter tone, you may think this is a little thing......IT NOT...
All just one mans finding...my reworked CSLs
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Thank you very much for great information, tyu.
I've read many other posts by you, which are also very informative. You've experienced much.
I have a pair of junk ML CLS 2a. The sound was favorable for me. They had rather flat response but with a certain level of distortion. They produced sound of more or less 75 dB, about 10 dB lower than the QUAD ESL 57 pairs that were briefly repaired by myself.
Now one of the pair has been disassembled.
I will remove the patches on the backside stator, since I will be able to stick them outside of the stator afterward to compare their presence and absence. I will also try different ways of stretching the copper tape as you've suggested.
I've read many other posts by you, which are also very informative. You've experienced much.
I have a pair of junk ML CLS 2a. The sound was favorable for me. They had rather flat response but with a certain level of distortion. They produced sound of more or less 75 dB, about 10 dB lower than the QUAD ESL 57 pairs that were briefly repaired by myself.
Now one of the pair has been disassembled.
I will remove the patches on the backside stator, since I will be able to stick them outside of the stator afterward to compare their presence and absence. I will also try different ways of stretching the copper tape as you've suggested.
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Sounds like low bias....I put the Acoustat type 5k bias in all my CLS....going to day to get a pr of CLS 2....So more work for me is a head....
Also I never pull the ML stock mylar....you well never get the soind ...or out output.. with new mylar!...even if you have to replace mylar...new bias feed copper yes, always.....it tuff to get to work right....I only pay vary little $$ for ML...if mylar rips...I get only parts...I never re-mylar!...
I re-coat the stock mylar..right at the new bias feeder an panel..Soap & key cabon...I NEver re-glue the panels back to gather...the frames well hold them togather.. I use tape on the two sides.....good luck
Also I never pull the ML stock mylar....you well never get the soind ...or out output.. with new mylar!...even if you have to replace mylar...new bias feed copper yes, always.....it tuff to get to work right....I only pay vary little $$ for ML...if mylar rips...I get only parts...I never re-mylar!...
I re-coat the stock mylar..right at the new bias feeder an panel..Soap & key cabon...I NEver re-glue the panels back to gather...the frames well hold them togather.. I use tape on the two sides.....good luck
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Here thay are....lot care with these....panels 22 years old...played one an one of my panle re-worket new bias feed...new coating....these play just as loud...An sound the same....sweet tone...lot fun
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Yes, I really need good luck.
I washed the units by shower water, insert a copper wire into the gap, put some detergent solution to improve contact between copper and membrane, and so on. No good results were obtained.
It is not wise to re-mylar on ML CLS types. Yes, I agree with you, tyu. But it's a hobby! One piece of CLS 2a was disassembled and the aged dirty membrane was already removed from the stator. Now, DS tapes and residual adhesive are being removed.
I'm trying step by step slowly, since I'm in a very tight budget. I got some materials and tools from 100-yen-shop (something like one-dollar-shop) nearby. It is fun to think how to give equal tension vertically to the membrane, how to coat the surfaces, and so on.
When it is successfully re-assembled, photos will be uploaded. I don't know when.....
I washed the units by shower water, insert a copper wire into the gap, put some detergent solution to improve contact between copper and membrane, and so on. No good results were obtained.
It is not wise to re-mylar on ML CLS types. Yes, I agree with you, tyu. But it's a hobby! One piece of CLS 2a was disassembled and the aged dirty membrane was already removed from the stator. Now, DS tapes and residual adhesive are being removed.
I'm trying step by step slowly, since I'm in a very tight budget. I got some materials and tools from 100-yen-shop (something like one-dollar-shop) nearby. It is fun to think how to give equal tension vertically to the membrane, how to coat the surfaces, and so on.
When it is successfully re-assembled, photos will be uploaded. I don't know when.....
One point....I had to start Solder ...wire to the bias feeder copper!...just laying it in dose not work right...As for your Mylar... well yes.... you well have to do the 2 panels the same....
But some people think thay just rip out the old mylar...like thay can just put in better..
well you can....but the ML... mylar is made for capacitor....with medal in it... an thay add a coating as well.....cant get this type...I never seen small amount sold.
Not saying it cant be done....I cant-wont... do it ....I only gave $300 US for my pr
But some people think thay just rip out the old mylar...like thay can just put in better..
well you can....but the ML... mylar is made for capacitor....with medal in it... an thay add a coating as well.....cant get this type...I never seen small amount sold.
Not saying it cant be done....I cant-wont... do it ....I only gave $300 US for my pr
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