Martin Logan electrostatic towers. How do they work?

[guitarplyrstevo]

I've auditioned a pair of some Martin Logan Electrostatic speakers the other day and was blown away by the fullness of the sound. I've tried to read about how it works but I was confused. I know a speaker cone makes its sound by making vibrations from a cone going back and forth, but how does the electrostatic towers create its sound?

 

[rumble]

I've auditioned a pair of some Martin Logan Electrostatic speakers the other day and was blown away by the fullness of the sound. I've tried to read about how it works but I was confused. I know a speaker cone makes its sound by making vibrations from a cone going back and forth, but how does the electrostatic towers create its sound?

An electrostatic loudspeaker is a loudspeaker design in which sound is generated by the force exerted on a membrane suspended in an electrostatic field.

wikipedia link - http://en.wikipedia.org/wiki/Electrostatic_speakers

You may also want to check out magnetic planar speakers made by Magnepan - http://en.wikipedia.org/wiki/Magnepan

 

[TLS Guy]

I've auditioned a pair of some Martin Logan Electrostatic speakers the other day and was blown away by the fullness of the sound. I've tried to read about how it works but I was confused. I know a speaker cone makes its sound by making vibrations from a cone going back and forth, but how does the electrostatic towers create its sound?

Well now you have heard a decent speaker!

The bass speakers are cone in the Martin Logan crossover about 450 Hz I believe. The bass is a sealed design. Depending on model the the F3 is from 44 Hz to 29 Hz.

The first electrostatic was introduced by Peter Walker OBE of Quad Electro acoustics, in 1957. Now known as the the Quad ESL 57. He started work on the Quad ESL 63 in 1963. Quad is now owned by International Audio Group, and are selling what are updated, and some say mucked up versions, of the ESL 63. Peter Walkers ESLs were full range.

http://www.quad-hifi.co.uk/ranges.php?sector_id=1

The Quad ESLs have electrodes fed from delay lines etched into the membrane to overcome the beaming of electrostatic panels.

Here is a bibliography on electrostatic speakers.

http://mark.rehorst.com/ESLs/esl_bibliography.htm

There are many DIY builders of electrostatics, as outlined in this post.

http://www.sacdmods.com/ESL/web2.htm

There are numerous books on the subject.

At least you have now heard a decent speaker and have a point of reference now.

 

[bandphan]

Which model/s did you demo?

 

[bandphan]

http://www.us.martinlogan.com/faq/faq_electrostatic.html

 

[Porschefan]

Well now you have heard a decent speaker!

The bass speakers are cone in the Martin Logan crossover about 450 Hz I believe. The bass is a sealed design. Depending on model the the F3 is from 44 Hz to 29 Hz.

The first electrostatic was introduced by Peter Walker OBE of Quad Electro acoustics, in 1957. Now known as the the Quad ESL 57. He started work on the Quad ESL 63 in 1963. Quad is now owned by International Audio Group, and are selling what are updated, and some say mucked up versions, of the ESL 63. Peter Walkers ESLs were full range.

http://www.quad-hifi.co.uk/ranges.php?sector_id=1

The Quad ESLs have electrodes fed from delay lines etched into the membrane to overcome the beaming of electrostatic panels.

Here is a bibliography on electrostatic speakers.

http://mark.rehorst.com/ESLs/esl_bibliography.htm

There are many DIY builders of electrostatics, as outlined in this post.

http://www.sacdmods.com/ESL/web2.htm

There are numerous books on the subject.

At least you have now heard a decent speaker and have a point of reference now.

Thanks for the reading material! A friend had us over this weekend and we heard a wide range of music played through a very old pair of Acoustat electrostatic panels. I was blown away by the clarity, sense of space and super stereo definition. Now I have to do some serious studying. I'm already looking beyond my Axiom M22's, QS4's and VP150. I can get a start on a Def Tech setup with a pair of BPVX surrounds at a GREAT price and I was heading in that direction. Now, I'm wondering if any "regular" speakers can produce that kind of sound? I see some Quad ESL-63's on sale at Audiogon too. Do you have any advice on which way to go? Start concentrating on electrostatics or stick with finding better quality "regular" speakers?

 

[WmAx]

Now, I'm wondering if any "regular" speakers can produce that kind of sound? I see some Quad ESL-63's on sale at Audiogon too. Do you have any advice on which way to go? Start concentrating on electrostatics or stick with finding better quality "regular" speakers?

The main problem is, the ESLs you heard are essentially free from most resonances. Very few 'regular' speakers can claim this - and those that can - are generally extremely high priced. And never assume a speaker is low resonance just because the manufacturer says so -- so many like to make such a claim and the reverse is true.

-Chris

 

[Porschefan]

The main problem is, the ESLs you heard are essentially free from most resonances. Very few 'regular' speakers can claim this - and those that can - are generally extremely high priced. And never assume a speaker is low resonance just because the manufacturer says so -- so many like to make such a claim and the reverse is true.

-Chris

So, what are the best choices for duplicating this kind of sound? Do you think Martin-Logan "hybrids" are on the right track?

 

[WmAx]

So, what are the best choices for duplicating this kind of sound? Do you think Martin-Logan "hybrids" are on the right track?

That is still a regular ESL. It just has a dynamic speaker for lower frequencies.

If you want an example of a dynamic driver speaker with ESL like clarity: refer to B&W 802D. Combine an 802D with a DSP controller like a Behringer DCX2496 and you would be in for a real treat - with basically no way to ever get any kind of substantially better sound from a conventional monopole. You can inexpensively add rear-firing ambiance tweeters if you want the back wave reflection cues like an ESL can provide, but most regular domestic environments don't have sufficient space to allow for speakers to be placed far enough from wall for this to work well. (Minimum 4 feet from rear of speaker to wall.)

-Chris

 

[bandphan]

So, what are the best choices for duplicating this kind of sound? Do you think Martin-Logan "hybrids" are on the right track?

While some of there current atf speakers give the same feel, martin logan's current offerings with one exception are all hybrids(they only make one full range panel) Dipole sound without resonances is what your liking, ribbon/planar speakers that have these traits are what you want. Bohlender Graebener also makes speakers you should demo.

 

[Porschefan]

That is still a regular ESL. It just has a dynamic speaker for lower frequencies.

If you want an example of a dynamic driver speaker with ESL like clarity: refer to B&W 802D. Combine an 802D with a DSP controller like a Behringer DCX2496 and you would be in for a real treat - with basically no way to ever get any kind of substantially better sound from a conventional monopole. You can inexpensively add rear-firing ambiance tweeters if you want the back wave reflection cues like an ESL can provide, but most regular domestic environments don't have sufficient space to allow for speakers to be placed far enough from wall for this to work well. (Minimum 4 feet from rear of speaker to wall.)

-Chris

Thanks, Chris. Right now I have Axioms: M22's, QS4's and VP150. Those are my first speakers and right away I wasn't real pleased, although I have to admit I still haven't taken the time to learn how to set them up as best as they could be. I got a very good deal on 2 used Def Tech BPVX's and thought I would start moving in that direction. Assuming I were to stick with Def Tech, what would be your recommendations for moving those speakers towards the kind of sound I seem to be smitten with? My budget is pretty limited so I'll have to do whatever I do piecemeal and just look for good buys on used whatevers... I did get good enough deals on both the Axioms and the Def Techs that I can probably get whatever $$ I have into them out if I decide it's better to go in another direction. I do think I need to settle down and stick with a plan at some and at least get a good set of matched speakers and get them set up correctly.

I'm not familiar with the Behrenger DSP controllers, but would something like that help put the Def Techs into the ballgame?

I just checked prices on the B&W 802D's you suggested, but I'm afraid those, and just about any of the electrostats are presently out of my budget, so I'm going to have to this on a gradient.

 

[Porschefan]

While some of there current atf speakers give the same feel, martin logan's current offerings with one exception are all hybrids(they only make one full range panel) Dipole sound without resonances is what your liking, ribbon/planar speakers that have these traits are what you want. Bohlender Graebener also makes speakers you should demo.

Thanks, Bandphan. See my response to Chris above. It seems I have a bit of a champagne taste/beer budget problem at the moment!

 

[bandphan]

Thanks, Bandphan. See my response to Chris above. It seems I have a bit of a champagne taste/beer budget problem at the moment!

If your patient, you can get a good deal. Even the BG bookshelves would be a thought and as for ml most dealers run a buy 1 get 1 free deal around years end. (not all models)

 

[WmAx]

Thanks, Chris. Right now I have Axioms: M22's, QS4's and VP150. Those are my first speakers and right away I wasn't real pleased, although I have to admit I still haven't taken the time to learn how to set them up as best as they could be. I got a very good deal on 2 used Def Tech BPVX's and thought I would start moving in that direction. Assuming I were to stick with Def Tech, what would be your recommendations for moving those speakers towards the kind of sound I seem to be smitten with?

I presume the BPVX is the surround speaker with multiple driver baffles? I highly doubt that is going to have any resemblance to the ESL sound characteristics that you liked so much.

My budget is pretty limited so I'll have to do whatever I do piecemeal and just look for good buys on used whatevers... I did get good enough deals on both the Axioms and the Def Techs that I can probably get whatever $$ I have into them out if I decide it's better to go in another direction. I do think I need to settle down and stick with a plan at some and at least get a good set of matched speakers and get them set up correctly.

I don't know of any speakers with no timbre distortion(resonance free) in this price range that would be suitable. There is a solution, if you would be willing to do some work yourself: you could use a pre-finished cabinet like those available at Parts Express, and modify the inside of the cabinet(the baffle comes off and ready to glue on -- so you have full internal access) to be non-resonant. Then you add in the appropriate high density acoustic stuffing, and use a driver and crossover design that has been proven to have a linear response. The popular Modula MT design comes into mind here. Once you have your non-resonant and linear mid-treble module, you can combine it with sterreo subwoofers, and use a DCX2495 to effect your preferred tonal response. If you want increased stage depth, you can simply add on a rear tweeter with a simple 2nd order crossover circuit and L-Pad to adjust level, or even use the DCX to control it, as it will have extra output channels available.

I'm not familiar with the Behrenger DSP controllers, but would something like that help put the Def Techs into the ballgame?

No. The only way the DSP gives you an ability to adjust coloration to preference, is if the device being manipulated has a neutral, or mostly neutral response to begin with. Otherwise, you are just adding coloration upon coloration, trying to mask what you don't like about the speaker.

I just checked prices on the B&W 802D's you suggested, but I'm afraid those, and just about any of the electrostats are presently out of my budget, so I'm going to have to this on a gradient.

I am sorry that I did not clarify. I simply believed that you wanted to know a model of dynamic speaker that matches some electrosat characteristics. I did not know that you wanted, specifically, a purchase recommendation.

-Chris

 

[Porschefan]

I am sorry that I did not clarify. I simply believed that you wanted to know a model of dynamic speaker that matches some electrosat characteristics. I did not know that you wanted, specifically, a purchase recommendation. -Chris

No problem. I wasn't and still am not clear on the whole subject due to lack of experience and reference points. I've poked around some more and discovered a manufacturer called Magnepan, which seems to have a full line of speakers using planar technology, including an incredibly inexpensive ($550/pair) small pair. There is a semi-local dealer who carries the Magneplan line as well as Definitives and other brands. I'm hoping to get over there and get a head-to-head comparison audition.

Any comments on Magnepan? (Don't mean to hijack this thread from the Martin-Logan questions, but I'm very interested in getting more data points on this subject.

 

[wreckingball]

Esl's

Once you hear electrostats, you can't stop thinking about them.
At least that was the way it happened for me.
Placement within the sound stage becomes truly 3D, and I couldn't look back.
That being said, there a lot of different variables to keep in mind, first off, your amp has to be strong enough to withstand the load/voltage swings, second, there is placement of the panels, at least a few feet from the wall, and third... What the hell are you going to do with all of that source equipment that now sounds like poo? LOL. In short, electrostats are truly a marvel to behold, (and hear) but they are as picky as a nagging wife as far as equipment goes, so beware.
Steve

 

[R-Carpenter]

There's no ideal or absolute speaker out there that will do everything perfectly.
M-L and Magneplanar offer certain advantages compare to conventional speaker designs and there's nothing else out there for the money that will do particular things just as good or better.
If you liked Logans so much, by all means, go get them and be happy. Keep in mind that electrostatics and magnetic planars are dipoles and cannot be placed against back wall. They also need a healthy power amp that will hold up to low impedance (think 2ohm)
I would also look in to Quad Esl 63.
The main disadvantage of ESL (as well as M-planar) is it's dependably on room boundaries and as a result jugged FR which is true for most dipoles. Hybrid Logan with conventional woofer is probably better.
I myself owned MG3.5R for 12 or so years and while I've build better speakers and decided to sell MG, I haven't yet and somehow I always come back to them and spin a CD.

 

[wreckingball]

Esl's in the News

Roger Sanders ( the inventor of the curved Esl) and author of "The Electrostatic Loudspeaker Design Cookbook" Has won the Las Vegas CES "Editors Choice Award" for the best system at any price category 2008. Now, I own a couple of his prototype esl's ( stuff that he has passed over in pursuit of the ultimate) and can say without a doubt that it is the best that I have heard.(that's a period) I can't even imagine what his current offering sounds like, given the advances he has made. Although, I'll have to live with what I've got , since I don't have 13'000 dollars to spend on that system... bummer
Cheers to all of you Audioholics
Steve

 

[hotroady]

Once you hear electrostats, you can't stop thinking about them.
At least that was the way it happened for me.
Placement within the sound stage becomes truly 3D, and I couldn't look back.
That being said, there a lot of different variables to keep in mind, first off, your amp has to be strong enough to withstand the load/voltage swings, second, there is placement of the panels, at least a few feet from the wall, and third... What the hell are you going to do with all of that source equipment that now sounds like poo? LOL. In short, electrostats are truly a marvel to behold, (and hear) but they are as picky as a nagging wife as far as equipment goes, so beware.
Steve

Yep! that's actually a good sumation, only thing to add..you'll probably want a sub.

 

[OttoMatic]

Any comments on Magnepan? (Don't mean to hijack this thread from the Martin-Logan questions, but I'm very interested in getting more data points on this subject.

Hi there,

I used to have the Magnepan MMG (pretty sure that's the one you're describing for $550). They are the introductory model, and they're quite impressive for the price.

They have a very open and detailed sound, similar to what you liked in the Martin Logan. They work using a different technology (magnetic vs. electrostatic), but both employ a dipolar panel to generate sound. They can very engaging when set up properly. Yeah, I highly recommend you visit that dealer and listen, listen, listen.

The Magnepan MMG is very commanding to have in your living room, and you will get lots of comments, even though they are only the "small" ones. I believe they are 48" tall and probably 18" wide. They are no thicker than a book and people will look twice at them. They are pretty cool, and will get to you into the dipolar panel speaker arena for a minimal outlay of cash.

They will need to be set up so that they are away from the wall behind them. I think I had a good two feet behind them, and it was OK. If I'd had more space, I probably would have pulled them out more. They will also like some room to the sides of them, and I was slightly limited in that regard. Still, they worked well for me. The M-Ls and Definitives that you mention will also want space behind and to the sides of them.

The Magnepan is a bit of a fussy load to drive, and the only speaker that I've owned that compelled me to buy an external amplifier (the Audio Alchemy OM-150, which is an excellent amp, and which is currently for sale by me cheap -- PM me if you're interested). I was using a Denon receiver at the time (circa 1999) and it just couldn't drive the MMGs. I believe they are a 4 ohm load, but I'm not sure about their phase response. Either way, I found that the receiver couldn't supply the necessary power at high volumes, and I got the amp. That took care of my power problems.

I also found that the MMGs were not the most dynamic speaker. They just don't have the "slam" of a big dynamic speaker. Of course, they only cost $550, so it's necessary to compare them to a dynamic speaker in the same price range. At the time, they had replaced the B&W DM602 (about $600/pr). The 602 was definitely had more presence in the mid-bass region, but didn't have the laid back lushness of the MMG. They are clearly different beasts; when you're at the audio shop, try to compare the Magnepans (I'm not sure they'll have the MMG; I thought it was direct purchase only for that model, but it was a while ago) to other dynamic speakers in the same price range using the same music, etc.

The MMG only has extension to about 60Hz, IIRC. I found that a sub was an absolute necessity, unless your musical tastes don't require sound reproduction that low. They just don't have any low end, so you'll need to add that in.

I've also owned Definitives (BP2002TL, center and surrounds), and I've auditioned some of the M-L electostatics (I believe they do make one or two fully dynamic speakers). The Definitives are bipolar while the M-Ls and Magnepans are dipolar (some decent discussion on that and other topics here). The Definitives were "OK" for me, but ultimately, I found them to be too bright. I know there are lots of Definitive fans here, and I must say that they are well-made speakers, but they just weren't for me. If you find yourself comparing Definitive against M-L and Magnepan, be sure to listen extensively and be sure you are making the right decision, regardless of what kind of deal you can get on one or the other. In the long run, a good deal now may cost you more later as you decide that you have to buy all over again to get the sound you want. I think you will find that they are quite different beasts, and you will know it when you hear it.

That's it for now. Good luck!