Martin Logan CLS "Buyer's Guide" Question

I’ve wanted a set of Logan CLS’s since I first heard them back in the 1980’s and would like to start looking for a pair, but could use some help to know for sure that I’d be buying a good set. Would you guys please opine on these concerns?

- What do I look for in a decent set to avoid a ’lemon’?
- What is the difference in characteristics between ’generations’ of CLS (I, Ia, II, IIa, IIz...)
- How can I identify which generation of CLS I’m dealing with, and how important is it?
- Would there be any concern about age of panels, or if the panels are replacements?
- Would you recommend a different model of ML speaker, and if so - which one, and why?

My current equipment is:
McIntosh C28 (presently in use)
Krell KRC-3 (inbound...)
Bryston 4BST
Dahlquist DQ10
Polk PSW650

I hope to replace the DQ10s in favor of the Logan’s, but it’s helpful to know what I’m getting into beforehand, to avoid a costly mistake.

Thanks in advance!

I was a Martin Logan dealer for many years and currently use a pair of CLSIIA’s as one of my reference speakers.

When I was a dealer, I always had a pair of the older model on demo when the new model came out. I was able to A/B them side by side.

The CLS I (there was never a CLSIA. Actually, it was just the CLS). These had a different pattern to the spars inside the panel and were easy to tell that they were the CLS versus the later model. The CLS would drop down to around .6ohms and was an amp eater.

The CLSII was designed to be a little easier on amps. These would drop down to around .8-.9ohms.

The CLSIIA was developed very shortly after the CLSII came out and was field retrofittable. It was a pretty easy mod to do and opened the speaker up quite a bit and smoothed it out over the CLSII, but still was pretty hard on amps.

The CLSIIZ was developed to be even easier on amps. These drop down to around 1.2ohms and did indeed help with the amp situation.

When I was able to hear them side by side through their evolution period, I liked the CLSIIA the best. Many owners will say the CLSIIZ was the best, but I’m not sure that everyone had the chance to hear them side by side. This is just my opinion, but Gayle Sanders once told me that he thought they had lost some of the "magic" & "sparkle" when they went from the IIA to the IIZ, but it had to be done to try to address the amp problem.

Martin Logan has a serial number decoder to help you know which version you have and to tell how old the electronics and panels are. I have a pdf copy if you want it.

The ML panels last around 12-15 years before they need replacement. Unfortunately, ML has really raised the prices of replacement panels. I replaced mine a few years ago for $890 plus shipping. They are now $2700 plus shipping.

There is a guy named Russ Knotts that will rebuild a pair for around $600 or so, (maybe a little more now).

The CLS series does require a careful in-room setup, but are something really special when done right.

Good luck on your search...
@mofimadness fantastic post I cannot imagine anything more helpful for the OP well done!
Ditto. This is a slam-dunk for information. Thanks for the help!

Just made a (sight unseen) deal on what looks to be a very nice condition pair that allegedly are the IIs (upgraded electronics) with replacement panels (SN CS1H1715, I think) that were done in ’02-ish. It'd be helpful if there were an easy way to identify the 1-series panel from the 2-series panel.  Though they’re *theoretically* toward the end of the 12-15 year lifespan, I also tend to think that the owner has much to do with that.

I guess I’ll just roll the dice to see. Stay tuned...
@parabolic...the serial number you list would make them replacement panels made in September 1996. They were the 15th replacement panel made that month, (according to the serial number decoder).

If the serial number is correct, then they are the CLS I panels. You really shouldn’t mix I panels with II electronics and vice versa. I know people do it all the time, but you really shouldn’t do it. The electronics for the original CLS are designed to only work correctly with the original panel design.

Here are a few pictures of the original CLS. You need to notice the horizontal and vertical spars inside the panel. They are not connected to each other and the spacing is the same from side to side. Also, some of the original CLS panels had just horizontal spars with no vertical spars.

Here are a few pics of a II series panel:

The II series have a little wider space on one side versus the other side and the horizontal and vertical pieces are connected to each other.

Also, the panels and electronics have different/separate serial numbers.
Hmmm... yeah, the photo he sent did show the gaps in the spars, so that would make 'em the I's, and his calculations on replacement year sadly mistaken, though I don't think he's done so intentionally.  You've given me a moment of pause, now.  What would you say is a fair price for this older set, or would you walk away? mentioned above that the speakers had upgraded II electronics.  The panels do seem to be the I series.  If you can get the serial numbers on the electronics, I can tell you what they are, unless the serial numbers were never changed to reflect the II series upgrade.

If it were me, I would walk away.  Correct CLS II speakers do pop up for sale.  Not quite as much as in the past, but still every so often.  I just am against mixing I & II panels and electronics.  They just don't sound right, if you know what they are supposed to sound like anyway.
I was told S# 2502/2503 (sequential).

What would be the danger if I were to buy this set now (because they are becoming somewhat rare) and later purchased the II panels at some point in the future?

How long would you say I might be able to run them, given the 19 year old stators?

What would you think is a fair price, under the circumstances?

Should I be looking at getting a newer generation pair of Logans (i.e. Theos) instead of screwing around with the CLS in the first place?
Those serial numbers would make them original CLS electronics.  Can't be sure unless I saw pictures of the insides, if they were modified/updated or not.

IMHO, the panels are already do for replacement.  You could sure use them, but you wouldn't be hearing them at full capability.

I wouldn't pay more than around $600-$800 for them.  It would also depend on what shape the frames are in and if the seller has the boxes and packaging for them.

The newer model Martin Logans are somewhat easier to setup and drive.  They have integrated the woofer with the panel much better than the earlier models, (the CLS is, of course, a full range speaker).

Still there is a definite "magic" about the CLS series that nothing short of the CLX or the mega expensive Neolith can match.  Once you hear them setup properly and driven with enough juice, they are hard to forgot.  Just like your first encounter with them back in the 80's.  That's why you're here at this juncture...correct?
That's why you're here at this juncture...correct?
At this juncture, I'm beginning to think I need to have my head examined.  ;-)

I've been wanting a set of CLSII's for years.  It's taken me this long to be able to afford to do so, because it's not just the speakers, but the rest of the system, that starts getting expensive.  You need an amp powerful enough to drive them, and a preamp clean enough to not make your ears bleed.  That equipment is far more costly than most folks expect to spend on a 'stereo'.  It was only recently - in the last couple months - that I've finally saved enough and been patient enough to stumble on the Bryston/Krell combo.

The seller claims that the electronics were upgraded by a local ML dealer, though if he's as mistaken about that as he is with the panels, it does give me a moment of pause.

I was prepared to drive 9 hours each way to buy 'em, but the asking price is more than you indicate and though they look by the photograph to be in very good condition, it's a LONG time to spend in a car and a LOT of money to lay out.

I'll probably beg off and wait it out.  My set of Dahlquist DQ10's don't suck, so I guess I'll just have to struggle through, until what I really want comes my way.

Thanks for all your help!!!
I think you're probably better off waiting also.  The right pair will come around.  The last couple pair of  IIZ's that I've seen were around $1200-$1500 dollars in excellent condition.

You're quite welcome and if you have any other questions or need any additional help, just let me know.
Very grateful for your assistance.  If you happen to stumble on a pair in the Northeastern PA region (keeping in mind I was ready to drive 9 hours each way for this pair), let me know.
If you happen to stumble on a pair in the Northeastern PA region (keeping in mind I was ready to drive 9 hours each way for this pair), let me know.

Will do.  I am always running into a pair somewhere.  I'll let you know.
i'm with jond on this one - really very nice of you mofimadness to help parabolic with some great & pertinent information.  
these sort of episodes make me believe that in fits & starts Audiogon is still the same as it was when i first joined......
@jond and @bombaywalla...thanks guys for the nice comments.  I really appreciate it!
Hey, guys. Just wanted to report in and say that I stumbled into a pair of mint condition ReQuests at a great price, so I couldn’t resist. They’re the newer design, production date in early 2000, and were in storage for some 5 or 6 years, so the panels are effectively about 10 years old.

If anyone has advice on tips, tricks, tweaks or general wisdom, I’m grateful for the input.

More props directed your way from this corner of the peanut gallery. Great to see this kind of contribution from fellow 'Goners.  It makes this a better place.
Excellent exchange.  Thank you mofimadness for sharing such good info.  I have a lead on a pair from a nearby estate sale...but now it appears they are original CLS panels.  You've helped me intelligently evaluate what I'm looking at.
Thank you!!
I would like to add to the kudos already given to Mofi for his advise.  I think he steered the OP in the right direction given the age of the speakers and other considerations.  Having said that, as someone who loves those speakers and who came very close to buying a pair of original CLS's when they were current I would like to add some thoughts to the mix of great info here.  

I listened to the original CLS's at length and several times at local dealers (Sound By Singer mostly) and one aquaintance before deciding to go in a different direction (Maggies).  For whatever it may be worth I remember clearly that the original CLS was generally considered by reviewers and at least a couple of CLS owners I knew to be "the one" with the magic and that the changes to the speaker up until the introduction of the 2Z to be improvements in amp friendliness and tonal friendliness by being less ruthlessly revealing, but also being somewhat of a step backwards in some ways.  The 2Z seemed to strike the best balance between all those considerations.  Fantastic speakers!
Someone needs to mention that those  dq-10s are not even close to any decent modern speaker.   Good move on the Requests.   Your logic is wrong on the years of not being used not counting.  If they sound good then thats great but realize they are gonna need new panels at some point.  Those are speakers worthy of new panels for sure.
Enjoy them
Must say that I still like the original CLS best of all, assuming you have an amp that will drive the load - they just seem to 'disappear' more than the later versions do.  Glad they still offer panels for them - will probably need them some day - these were low use and should have some miles left unless the panels just 'age out' - do they do that?

I have a main system with regular dynamic drivers that is great for most things, but if I want to listen to violin or harpsichord, I head for the second system.
Panels can be rebuilt, per the ML Owner's forum.  I got in touch with the guy who does the work and he quoted $500 for a set of ReQuests with newer and better coating on the mylar and upgraded contact strips all the way around.  Not too bad, all things considered.