the CLS II revisted

[puroagave]

yesterday I acquired a previously loved pair of CLS IIs with a birth date of oct '93 and both panels replaced at least once during its life with a verifiable chain of ownership. after more than 9 prs of panel speakers, 5 of them ESLs, I'm surprised I never owned a set of martin logans. I've heard plenty of them, the monolith for one was a speaker I always wanted to own but never did. I first heard the original CLS back ca '87 and subsequent versions in later years it wasn't love at first listen but they were an intriguing proposition.

I wasn't really looking for set but a local pair came up, no shipping expenses and at an agreeable price so a deal was struck. i've had these in the system now for about a day and a half and they're sounding good - but not great. my first impression is the lack of high freq extension, even for an ESL its a little dark. the low bass is absent, like nothing in the bottom octave and a half maybe two. I haven't tried the test tones on the stereophile disc to confirm what i'm hearing but my quad 57s have better 'perceived' extension at both extremes so its got me wondering. the panels have a strong output and the sensitivity seems to meet spec based on where my volume control is at, theres no buzzing or 'kazooing' nosies from the panels of any kind and the channel balance is dead even.

So i'm looking for some pointers, or tell me there's something wrong with my pair or yes, my initial observations are consistent with the CLSs character. I have plans to raise them on stands and maybe add a sub. lm looking for suggestions on all of the above.

 

[mep]

There shouldn't be a lack of high frequency extension if they are working correctly. What amp are you driving them with?

 

[puroagave]

spectral dma-150s, dma-80 and right now a rogue w/ KT120s

 

[Gregadd]

Congratulations!
First the panel have a serial number on them. Get that number and contact ML to determine the true age of the panels. They may need to be replaced. Instructions for contacting no are located on this site under ML
Room placement e is critical. A classic tube is not the best choice for frequency extension.
.

 

[puroagave]

thanks Greg. upon further investigations my panels are >10 yrs old, that said i'm getting accustomed to them and the potential is def there and i'll prolly acquire new panels soon. I discovered the MLO site and registered, I see you're a member too. catch you on the flip side.

 

[MylesBAstor]

thanks Greg. upon further investigations my panels are >10 yrs old, that said i'm getting accustomed to them and the potential is def there and i'll prolly acquire new panels soon. I discovered the MLO site and registered, I see you're a member too. catch you on the flip side.

It's been a while but IIRC, the IIs were far from the easiest of the CLSs to drive.

 

[DonH50]

^^^ True dat. And the impedance of ESL's dips as frequency increases. I have always loved a good tube midrange on an ESL but IMO the highs and lows suffered greatly. And, despite my love for panels in general, I have found full-range offerings often suffered from bass "bloat" and rolled-off highs. It is very difficult to design and drive a full-range panel.

That said, I suspect some (if not most) of the issue is the panel's age and cleanliness. 'Stats tend to attract dust and debris, not to mention get coated with chemicals from e.g. smoke and air pollutants, and that degrades their performance over time.

It has been a long time, but way back when and IMO the CLS line was not as clean as the Quads or some of the other systems (some Acoustat, Beveridge) that did not try quite as hard to achieve full-range performance.

 

[microstrip]

yesterday I acquired a previously loved pair of CLS IIs with a birth date of oct '93 and both panels replaced at least once during its life with a verifiable chain of ownership. after more than 9 prs of panel speakers, 5 of them ESLs, I'm surprised I never owned a set of martin logans. I've heard plenty of them, the monolith for one was a speaker I always wanted to own but never did. (...)

One of my top five sound reproduction experiences was listening to the Monolith III's driven by Mark Levinson 20.6 using Transparent Audio top cables. The more realistic reproduction of a big choir I have experienced - you could easily feel the sections of the choir, and inside them individual singers in a very natural way.

Congratulations on your choice - the CLSII are great speakers!

 

[Gregadd]

L am a former member. Age is nor automatically an indication that panel should be replxed. The new panels are better. Some of the complaints you made are consistent with panel wear. A good amp like the Moscode 402au is definitely required

thanks Greg. upon further invetigations my panels are >10 yrs old, that said i'm getting accustomed to them and the potential is def there and i'll prolly acquire new panels soon. I discovered the MLO site and registered, I see you're a member too. catch you on the flip side.

 

[MylesBAstor]

^^^ True dat. And the impedance of ESL's dips as frequency increases. I have always loved a good tube midrange on an ESL but IMO the highs and lows suffered greatly. And, despite my love for panels in general, I have found full-range offerings often suffered from bass "bloat" and rolled-off highs. It is very difficult to design and drive a full-range panel.

That said, I suspect some (if not most) of the issue is the panel's age and cleanliness. 'Stats tend to attract dust and debris, not to mention get coated with chemicals from e.g. smoke and air pollutants, and that degrades their performance over time.

It has been a long time, but way back when and IMO the CLS line was not as clean as the Quads or some of the other systems (some Acoustat, Beveridge) that did not try quite as hard to achieve full-range performance.

Not so much in the new MLs. They have incorporated a circuit that cuts off the panel when it doesn't see signal after a period of time.

 

[microstrip]

Not so much in the new MLs. They have incorporated a circuit that cuts off the panel when it doesn't see signal after a period of time.

Also there were huge technical improvements in the quality of the more recent Mylar coatings - they are supposed to last much longer. But an heavy smoker environment is not the best for electrostatics long term performance.

 

[MylesBAstor]

Also there were huge technical improvements in the quality of the more recent Mylar coatings - they are supposed to last much longer. But an heavy smoker environment is not the best for electrostatics long term performance.

Nope

 

[Gregadd]

I did wash my panels on the shower with no damage. Instructions ate on the MLO site. On paper. The speaker is a nightmare. In reality it is a dream come true.

 

[mep]

I did wash my panels on the shower with no damage. Instructions ate on the MLO site. On paper. The speaker is a nightmare. In reality it is a dream come true.

Did you try running them through a car wash? I bet that would really get them clean.

 

[microstrip]

I did wash my panels on the shower with no damage. Instructions ate on the MLO site. On paper. The speaker is a nightmare. In reality it is a dream come true.

A good friend recovered a pair of very old SL3 panels that were sounding dull using this technique. For safety he gave them a last wash with distilled water and dried them with compressed air at moderate pressure.

 

[mep]

I'm pretty sure if I got to the point where I felt the need to take a shower with my electrostats, I would probably just buy new panels. Besides, I'm not sure you could trust them if you dropped the soap.

 

[JackD201]

i'm pretty sure if i got to the point where i felt the need to take a shower with my electrostats, i would probably just buy new panels. Besides, i'm not sure you could trust them if you dropped the soap.

rotfl!

 

[JonFo]

Puroagave, to your questions about setup and such:

First, please try an amp that is designed to drive these highly complex loads such as the Sanders ESL amp. I just got one four months ago and it transformed my Monoliths, it has an ability to drive those big panels like no other amp I've ever tried. Mid-range and upper bass is improved, as that amp delivers the amperage to move those large panels.
Sanders offers a free 30 day in-home trial. Please do yourself a favor and check it out. Pricing is very reasonable considering the results.

Second, there is no such thing as 'full range ESL', IMHO, the CLS should be crossed-over no lower than 60Hz using a very steep (48dB/octave) crossover to a good sub. that will clear up the mid-bass and actually give you the lower fundamentals that your are missing today.

As others have noted, room placement is critical with dipole ESL speakers, as is appropriate room treatments. My advice is to start with a pair or Realtraps Minitrap HF (they absorb high frequencies) placed 3" off the wall *behind* the speakers. this will absorb the out-of-phase mid-bass and help clear up that important range. it also reduces the comb-filtering effects in the higher frequencies to clean up the highs.

Since you joined the MLO forum, please see my postings in the Room acoustics sub-forums for further input on this important topic.

finally, congratulations, sounds like you scored a good deal, I hope you get great enjoyment from this set.

 

[es347]

I'm pretty sure if I got to the point where I felt the need to take a shower with my electrostats, I would probably just buy new panels. Besides, I'm not sure you could trust them if you dropped the soap.

Mark you've made the case for soap-on-a-rope I have a pair of Aerius-i's and one panel crapped out. I replaced both and the cost was minimal...something around $150 per panel as I recall. They may not still build panels for the CLS however..

 

[MylesBAstor]

AFAIK panels for the CLS-and at thst improved-are still in stock.