Options for refreshing/replacing my 28 year old CLS speakers.

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Carlsbad

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So I came into a 28 year old pair of CLS speakers. I listened to them for a couple of months. They exceeded my expectations for clarity, resolution, soundstage, and especially excelled with wonderful vocals. But eventually I started hearing the weaknesses and I have to conclude they need new panels. So I set them aside and I'm listening to other (very good) speakers while I work on this. I'm not in a big hurry but after a few months of listening to the other speakers, I realize I want to get back to what I see as the advantages of a large planar speaker. And these speakers have a bigger panel than even the top-of-the-line MLs today.

1. So I called Martin Logan, $3K for new panels. That is option 1 and not at all out of the question. Having a basicly new extremely large panel pair of speakers for $3K sounds like a good deal. Might need to consider replacing transformers or perhaps some capacitors....ML does not have any replacement parts for these speakers other than they can make new panels.

2. I've had one knowledgeable member mention perhaps washing them. Perhaps that is an option. Need instructions if anyone has them.

3. I have a friend that likes his CLS IIz s better than the CLS. If I'm going to buy a $3000 pair of panels, maybe first I should buy a pair of CLS IIz and then refresh them?

4. If members here think I'm sending good money after bad, I could instead put the money toward a pair of 11a's or 13a's.

5. Or there are other good used MLs I see out there like Summits, or Vantage....haven't listened to either.

6. I'm willing to listen to other ideas.

Bass isn't an issue as I have a pair of HSU Research subs that blend nicely.

Thanks in advance for your ideas.

Jerry
 
I have no experience with the CLS or CLS IIz, so I can't speak to their qualities.

I *can* say that re-paneling (with ML panels) my Aerius was both very easy and incredibly rewarding, well worth every penny.

If I were you, I'd inquire about the price of CLS IIz replacement panels. If they still fit within your budget and others comment that the IIz are a considerable improvement over the CLS, it may be time to search for used pair of IIzs....
 
The replacement panels for my Prodigy speakers were about $3000 too. It looks like your panels are the same height as mine, 48 inches. Not sure about width. I replaced just that and nothing else and they sound great now. Mine are 21 years old, made in 2000.

If I were you, id just replace the panels. If youre going to do it, do it early because it could take 6 months or more to get it done. Mine took about 5 or 6 months I think. Kinda lost track. Well worth the wait.

If you replace the panels and still dont like the sound, worst case scenario you could sell them to someone and at least recover what you have in them. If youre tech savy then you could replace the electronics in them. Myself, I would end up taking them into the store I buy my ML stuff at and have them do the work for me.
 
I have no experience with the CLS or CLS IIz, so I can't speak to their qualities.

I *can* say that re-paneling (with ML panels) my Aerius was both very easy and incredibly rewarding, well worth every penny.

If I were you, I'd inquire about the price of CLS IIz replacement panels. If they still fit within your budget and others comment that the IIz are a considerable improvement over the CLS, it may be time to search for used pair of IIzs....

The CLS IIz panels won't work with the CLS exlectronics so I'd have to fine an inexpensive pair of CLS IIzs that need new panels...but that is possible.
 
Another option if you're not in a hurry, you can ship your panels to Russ Knotts for reconditioning. This was one of the options I was considering before pulling the trigger and purchase the replacement panels from Martin Logan. I still have the old panels of my ReQuests and I will send them to Russ for reconditioning so I have a back up set of panels. Russ quoted a price of around $700 for reconditioning my ReQuest panels. Very reasonable.

ESL Repair website
 
Repanel, verify/update electronics and if you don't have a sub(or two), add. Having listened to this combination several times I think you would be in heaven, only bested by new CLX/sub combo IMO.
 
Repanel, verify/update electronics and if you don't have a sub(or two), add. Having listened to this combination several times I think you would be in heaven, only bested by new CLX/sub combo IMO.
Thanks Dave. I'm thinking the same thing.
 
My experience - CLS II repanel in Feb. alternating with ESL 11A. The 11A is better in terms of detail and of course no need to play with subs. More than adequate bass for me.
That being said they are the coolest speakers on earth. Agree with Dave, I am now going to work on the electronics with a friend over the winter as I believe there is more potential there.
It's similar to a vintage car. If you want to listen to your music without fuss a pair of used 11A's (or better 13's) might fit the bill.
The CLS ( which apparently is quite different from the late models) will take some work to get there. Best to hear the new ML's if you can- you might be surprised.
 
I have a pair of CLSiiZ's and the electronics are different between each version of the CLS. The original CLS were very hard on amps because they would dip to under 2 ohms. The CLS iiA were an improvement and the last version which is the iiZ was a culmination of improvements and was a little easier to drive. Mine were originally iiA's and were upgraded at the factory to iiZ's by the original owner. I am guessing but I think that was about 15 years ago. I would look for iiZ if possible. The originals are very good but I believe they lacked bass(?) The newer panel design did help that. There are a few "tweaks" out there for the CLS which does help. I did do a couple of them and it was subtle but noticeable.
Good Luck.
If you need any more confusion and advice, you can email me at "[email protected]"
Jeff
 
I have a pair of CLSiiZ's and the electronics are different between each version of the CLS. The original CLS were very hard on amps because they would dip to under 2 ohms. The CLS iiA were an improvement and the last version which is the iiZ was a culmination of improvements and was a little easier to drive. Mine were originally iiA's and were upgraded at the factory to iiZ's by the original owner. I am guessing but I think that was about 15 years ago. I would look for iiZ if possible. The originals are very good but I believe they lacked bass(?) The newer panel design did help that. There are a few "tweaks" out there for the CLS which does help. I did do a couple of them and it was subtle but noticeable.
Good Luck.
If you need any more confusion and advice, you can email me at "[email protected]"
Jeff
Jeff, Thanks. I spent 90 minutes talking to Russ Knotts, the old man of electrostatic speaker tweeks, today. He helped me understand the things you just said about the CLS vs CLS IIA and CLS IIz. Now the "hard to drive issue I have solved with a behemoth amplifier, plus I listen mostly at low volume. The bass issue (which according to Russ is caused by saturation of the single transformer, thus the change to 2 transformers) I have solved with a great subwoofer. Russ suggested I should use a crossover to turn off the bass to the CLS just to save wear and tear on the panel since the bass is the long period movements that stretch the membrane. So I think I've got most of the improvements covered, however, being a purist, I would like to make sure I do so if I saw a pair of CLS IIz s in good shape at a reasonable price I would grab them, just as you suggest. --Jerry
 
I vote for 13A's. The newer you can get them the better. Hopefully 10 year old or less. Good Luck!
I hear you. And if this evaluation goes on a few months and I need to figure out what to buy myself with my bonus, that might be the way I go. Sometimes it's best to just spend the money and be happy.
 
Another option if you're not in a hurry, you can ship your panels to Russ Knotts for reconditioning. This was one of the options I was considering before pulling the trigger and purchase the replacement panels from Martin Logan. I still have the old panels of my ReQuests and I will send them to Russ for reconditioning so I have a back up set of panels. Russ quoted a price of around $700 for reconditioning my ReQuest panels. Very reasonable.

ESL Repair website
Spoke to Russ. Great guy. Still doing limited work but not full time. Told me the CLS is one of the most difficult to obtain success in rebuilding and went so far as to recommend buying the new panels if I have "deep pockets". Had a great discussion and much better understand the issues I face. Made some points in favor of Keeping/refurbishing the CLS, upgrading to the CLS IIz, upgrading to the new 13a, or buying the pair of Monti's I've found locally. So even though I still have a lot of confusing data, I feel less confused. :)
 
Glad to be of some help in this matter. Now, you have more data points to make informed decisions. Best of luck.
 
If Russ is willing to rebuild the Panels I would go that direction. If his price isn't much more than the $700 he previously charged, it give you a working pair of speakers at a very reasonable price. You can still keep looking for a pair of CLS IIz while enjoying the originals.
If you decide the IIz's are the speakers for you there is always someone looking for an original pair with good panels. You won't have $3000 invested in the new panels and a sale price would be great for the buyer.

I have owned CLS original, IIa and IIz. Jeff's information is spot on with the models. IIa had the best bass to my ears. I still sold them and kept the IIz.
 
I have a pair of CLSiiZ's and the electronics are different between each version of the CLS. The original CLS were very hard on amps because they would dip to under 2 ohms. The CLS iiA were an improvement and the last version which is the iiZ was a culmination of improvements and was a little easier to drive. Mine were originally iiA's and were upgraded at the factory to iiZ's by the original owner. I am guessing but I think that was about 15 years ago. I would look for iiZ if possible. The originals are very good but I believe they lacked bass(?) The newer panel design did help that. There are a few "tweaks" out there for the CLS which does help. I did do a couple of them and it was subtle but noticeable.
Good Luck.
If you need any more confusion and advice, you can email me at "[email protected]"
Jeff

Jeff, good to hear from you !

We are all still missing our old friend Dan (DTB300) !!
 
Update:
Thanks for all the helpful comments.

As I study the various generations and changes in the ML speakers, I see mostly changes to the way bass is handled. There hasn't been a lot of changes in the way the electrostatics are driven.

If anyone thinks I'm mistaken here, and I very well, could be. Please let me know.

That said, I can eliminate the need for a new 11A or 13A because I have bass drivers that I am very happy with. I may even put in a low frequency crossover to eliminate the bass frequencies going to the electrostats.

So looking at the electrostatic panels, I made a table of the electrostatic panel areas:

ESL 9A 405 in2
ESL 11A 484 in2
Montis 497 in2
ESL 13A 572 in2
ESL 15A 690 in2
CLS 1008 in2

This is an argument for sticking with the big panel old speaker. I think I'd like to upgrade to the CLS IIz which is newer but that may not be necessary. The biggest improvement in the CLS IIz was dual transformers which again, handle the bass better.

So my plan from here is:

1. Get a high voltage probe. Measure the charge on the panels of my CLS and see how they are performing vs specification.
2. Wash them, see how they perform.
3. Refinish the wood while I have them apart.
4. Make a decision on a new panel from Martin Logan.
4a. Decide if I want to upgrade to CLS IIz before ugrading.


BTW, if anyone has an extra HV probe or has one they don't use any more and wants to sell it let me know. The one recommended to me is the B&K BR-28A that I can find new for $70. Others will work too. Need 100 or 1000 to 1 voltage reduction.

If anyone has a pair of CLS IIz they want to part with, especially one that needs new panels, I would be quite interested.

thanks,
Jerry
 
Update:
Thanks for all the helpful comments.

As I study the various generations and changes in the ML speakers, I see mostly changes to the way bass is handled. There hasn't been a lot of changes in the way the electrostatics are driven.

If anyone thinks I'm mistaken here, and I very well, could be. Please let me know.

That said, I can eliminate the need for a new 11A or 13A because I have bass drivers that I am very happy with. I may even put in a low frequency crossover to eliminate the bass frequencies going to the electrostats.

So looking at the electrostatic panels, I made a table of the electrostatic panel areas:

ESL 9A 405 in2
ESL 11A 484 in2
Montis 497 in2
ESL 13A 572 in2
ESL 15A 690 in2
CLS 1008 in2

This is an argument for sticking with the big panel old speaker. I think I'd like to upgrade to the CLS IIz which is newer but that may not be necessary. The biggest improvement in the CLS IIz was dual transformers which again, handle the bass better.

So my plan from here is:

1. Get a high voltage probe. Measure the charge on the panels of my CLS and see how they are performing vs specification.
2. Wash them, see how they perform.
3. Refinish the wood while I have them apart.
4. Make a decision on a new panel from Martin Logan.
4a. Decide if I want to upgrade to CLS IIz before ugrading.


BTW, if anyone has an extra HV probe or has one they don't use any more and wants to sell it let me know. The one recommended to me is the B&K BR-28A that I can find new for $70. Others will work too. Need 100 or 1000 to 1 voltage reduction.

If anyone has a pair of CLS IIz they want to part with, especially one that needs new panels, I would be quite interested.

thanks,
Jerry

I was reading your speaker panel size table and previous posts stating that larger panels are always best.
In the case of bass reproduction, that's a no brainer.
But, when the panel is crosses at over 300hz, I have some doubts.
Everybody loves the CLZ Art, and if you look at that speaker specs, the mid/high panel is only 490in2
Do you all say that a 13a or 15a should sound better than a CLZ Art at frequencies above 3xxhz due to panel size?
 

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