Question for current ML CLS Owners

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Hey all,

If anyone has ML CLS (any model) can you confirm what the seated dimension inside the frame is?

These panels flex in (compress) and fit inside the frame, and remain compressed - I am making my own frames and would like to know what that designed seated dimesion is - uncompressed panel is around 23.5" and I am guessing that the compressed dimension is 23"? Can someone confirm?

Also, I have confirmed that the bass of the CLS panel definitely improves with the panel compressed in the frame (haven't yet confirmed HF improves, but should with added tension).

I have a pair of panels that had a bad "Kazoo" problem that seems to lessen/go away if they are compressed further - seems to be that over time, the mylar gives a tiny bit and loosens up - maybe a simple fix to the "Kazzooing" is a shim between the frame and panel??

Anyway, I appreciate the help...
 
If I understand what your asking and maybe I,m wrong but the width has nothing to do with compression but the slotted groove that clamps the front to back dim. Around the perimeter is what determines its rigidity?
The width should just be slightly snug?
One bad idea that the CLS did was to use hard woods that are too high Q that adds to frame resonance. It sure looks nice but if you could make a sealed area to add sand or better, this would surely look good and keep the frame inert. Painted MDF is another option and somewhat self damping.

Regards
David
 
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Hmmm, so the panel is not compressed into the frame adding additional mechanical tension to the membrane? Just slightly snug?

OK, I stand corrected. I made my frames (that the panels fit in) out of wall shelf mounts - (the ones that are 4 feet long with double slots where the shelf brackets insert). I made them exactly 23" wide and had to compress the panel (with new installed 12 micron mylar) into the frame...the mylar starts to "saddle" around the wider spacers...

Anyway, I will try them again uncompressed and see how they fare...

Thanks for the help!
 
Here one...

One bad idea that the CLS did was to use hard woods that are too high Q that adds to frame resonance. It sure looks nice but if you could make a sealed area to add sand or better, this would surely look good and keep the frame inert.

Painted MDF is another option and somewhat self damping.


This is funny....Magnepan owners for years have found that the MDF sounds like crap...an pay Big $$ for all wood frames...Wood takes bad vibs an turns them into heat an takes them away from the drivers...MDF feed it back too the drivers an sounds bad....I have heard the diff... it BIg...Martin logan new this.......goodluck
 
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tyu - yes, I have seen that vid, and yes, there does NOT seem to be much side compression of the panel - as AVWERK indicated - it appears just "snug"....

I replaced the mylar on the CLS with 12 micron aluminized (no coating) as a test and came out with decent results - I just have way too much side tension causing the "saddling" of the mylar in between wider spacers...since panel stators are not glued together, it takes no more than an hour to open the panel and re-mylar, so I can rip it all out and start over easily...this is ideal for routine cleaning and maintenance of panels.

Also - I don't know if Maggie owners ditch stock MDF for solid wood for any reasons but appearance.
 
I have a pr of stock CLS here an there compressed ....say what you well...hope that works out for you...

Also - I don't know if Maggie owners ditch stock MDF for solid wood for any reasons but appearance.

Well then you have not look at the mill post on all wood frams.....lot more than looks.... Magnestans... peter Gunn.Has done the work......but your not doing maggys now...i gess you can say any thing ....i try to say only what i have seen an heard!....goodluck
 
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Jan, Sorry,don't understand - is there a difference? Sorry for my Ignorance...the use of metalitized mylar was purely an experiment...not exactly sure what I think, it does work and produces nice sound...

I was thinking a high res membrane would not be able to recharge as quickly as a low res membrane, and thus be that much more responsive to music demands...

Thread where I got the idea for Aluminized foil (extremely cheap BTW)

Building an Electrostatic Speaker

Now discussions around the cons with Metalitized mylar:

http://www.diyaudio.com/forums/planars-exotics/51103-harold-beveridge-esls.html#post574466

And the pros of using it from same thread (great thread BTW):

http://www.diyaudio.com/forums/planars-exotics/51103-harold-beveridge-esls-2.html#post719626:
 
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Tyu
Maybe this will explain what I,m mentioning
Take 2 speaker enclosures. Build one with all hard woods and build the other with fine MDF. Same construction, internal braces as dead as you can make it but the same dimensions for both.
Now put a strip strain gauge to measure panel resonance as say Stereophile does. Which one of these will show less panel excitement? The mdf panels will be better damped overall under these conditions.
I believe it was Peter Acell that measured a severe frame resonance back at its introduction, but that was a long time ago..
The original CLS had a compressed glue joint frame if thats what is being discussed, but hard woods are to "ringy" in comparison IMO.

Regards
 
Some CLSs....maybe MDF with viner...the pr i have look like wood
But i have heard the Magnepans driver put in real wood... An ribbons an ESL panels in wood big diff in sound.... you can find real time input on the web from others....the sound is For the better.... geting any maggy driver out of the MDF is a great move sound wise....MDF as you say Is well damped... Dead.... an sounds Dark an can suck the life out of the sound...MDF cant get rit of the heat from the vibs so where do thay go back into the driver..
But if you like what you hear from MDF ...What ever it takes to get good sound....you got go with what you like
I cannot hear measurments..I can hear diff
I like tube amps an tube preamps that are over 60years old.. with 60year old tubes....Like HHscott an H/K.. an thay test bad....but sound sweet to me...goodluck
 
This is some info from Peter Gunns site...
I was only talking about panel speaker myself....But there a lot of post on wood frams ...goodluck


MDF is used in cabinet speakers because there you want to kill the rear wave inside the cabinet and since MDF refuses vibration it keeps it inside until the fill that speakers get packed with can absorb it. However on a maggie refusing this vibration causes all the energy generated by the driver to stay on it, which in turn causes all subsequent wave fronts to be broken up and smeared. Wood naturally and without hesitation absorbs and dissipates vbration, leaving the driver to play as clear and natural as possible. People who have owned the best electrostats have told me that once modded in my frames maggies equal and even beat them in regards to midrange clarity.
 
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Don't know if anyone is still following this, but I have noticed a few things with the Metallic mylar on the CLS panels... They are sounding very clean and crystal clear with Bias set to around 2500v.

I have them on Acoustat Medallion MK-131 interfaces (100hz crossover removed and replaced with a 1 ohm resistor) and to bring down the bias (sizzles like crazy at 5kv), I have the I/F on a variac to dial in the best sounding voltage...

I have the setup biamped with a DCX-2496, 250hz and up going to the CLS and below going into apair of Acoustat Model 3's...

This is getting interesting...
 
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