Yes, Rick did update some models, and basically did the right things while keeping the bev basics the same. The new Model 3 he made was spot on: he removed the woofers from the main tower, and then shrank the size of what remains (the electrostatic element, wave guide and back damping) into a much smaller enclosure. The Model 3 is huge, heavy, and really ungainly.
Sadly his business failed.
I haven't had much chance to experiment with placement. As I mentioned, the room in which they currently are placed is very difficult -- it is shaped oddly, and there seem to be openings (like doors) in all the places where one might try different things. There is only one spot where we can try the "Beveridge configuration" where they face each other on opposing walls, and have not tried that yet.
My guess is that the main thing that will change is the imaging. They were designed to be put against the wall; the issue is what happens to the reflections. There may be some minor frequency response variations, but I expect those to be comparatively minor. And with the imaging, I would think that the primary important thing are the reflecting surfaces other than the back wall. That probably matters more. But I cannot check a lot of this in my current room (we're working on it).
My 500 Hz number is arbitrary, and yes, you probably would need a tower of smaller woofers (dipole? sealed? cardiod?), pay attention to matching the radiation pattern, and be careful with the crossover. You'd probably also need a subwoofer.
Calvin on this board has a traditional ESL that is set up this way. You may wish to look for it.
Sadly his business failed.
I haven't had much chance to experiment with placement. As I mentioned, the room in which they currently are placed is very difficult -- it is shaped oddly, and there seem to be openings (like doors) in all the places where one might try different things. There is only one spot where we can try the "Beveridge configuration" where they face each other on opposing walls, and have not tried that yet.
My guess is that the main thing that will change is the imaging. They were designed to be put against the wall; the issue is what happens to the reflections. There may be some minor frequency response variations, but I expect those to be comparatively minor. And with the imaging, I would think that the primary important thing are the reflecting surfaces other than the back wall. That probably matters more. But I cannot check a lot of this in my current room (we're working on it).
My 500 Hz number is arbitrary, and yes, you probably would need a tower of smaller woofers (dipole? sealed? cardiod?), pay attention to matching the radiation pattern, and be careful with the crossover. You'd probably also need a subwoofer.
Calvin on this board has a traditional ESL that is set up this way. You may wish to look for it.
On horns, I know few particulars, but generally follow the area on this board. My understanding is that some of the newer profiles and materials have helped a lot to get rid of the traditional horn sound, which I don't like much either.
I mentioned the one I heard, which had a large horn that went from 100 Hz or so to 5 kHz (that's a guess, but it should be in the ballpark) before crossing to a Raal ribbon tweeter. It was outstanding. There was no bass to speak of, but he was working on the woofers.
I still think that if you are after high SPLs, you are better off exploring that route. Keep what you have, and give it a try. It will not be inexpensive, though.
Finally, you should check your preferred SPLs with a meter. You don't mention if these are continuous or peak SPLs, but if the are continuous, and the meter confirms it, I would be very concerned about hearing damage. Those levels will do it in short order. For comparison, a symphony orchestra typically does not exceed 90 db continuous, though peaks of course may be much higher but of short duration.
I mentioned the one I heard, which had a large horn that went from 100 Hz or so to 5 kHz (that's a guess, but it should be in the ballpark) before crossing to a Raal ribbon tweeter. It was outstanding. There was no bass to speak of, but he was working on the woofers.
I still think that if you are after high SPLs, you are better off exploring that route. Keep what you have, and give it a try. It will not be inexpensive, though.
Finally, you should check your preferred SPLs with a meter. You don't mention if these are continuous or peak SPLs, but if the are continuous, and the meter confirms it, I would be very concerned about hearing damage. Those levels will do it in short order. For comparison, a symphony orchestra typically does not exceed 90 db continuous, though peaks of course may be much higher but of short duration.
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Took a while, but the thread eventually got to realizing that 'dynamic sounding' is a subjective impression and 90% independent of technical terms like 'dynamic range' and 'maximum loudness and slam at every frequency -- maybe without distortion too'.
I think I am within my rights to ponder how much of that subjective impression is autosuggestion.
I don't exempt myself. I am yet to hear an ESL that I don't think sounds just a little lifeless. Could be imaginary. Although the one audition I most keenly anticipated was ruined by the owner playing at a volume I would call completely unengaging -- I would guess 60 dB, I kid you not -- and responded to my plea for more volume by turning it up about 3 dB. Maybe his DIY masterpieces had an Achilles' Heel that he wasn't going to show me....
To repeat: I'm not talking about playing loud. Once, playing music at home with a friend, I switched from my sat-sub to my horns (I had matched the loudness) and my friend said "not a small increase in dynamics there". We were playing at about 75 dB: he hates loud. Yet he sensed a dramatic increase in 'dynamics'. Was he imagining it? Since he made that comment, I think I hear it too, but maybe his suggestion influenced me.
If it is autosuggestion, then horn = highly dynamic, cone = middling dynamics, ESL = flat dynamics messaging has got to us all. 'Us all' in the general sense.
But if it is real, and at ear-preserving volumes, then something other than massive SPL ability is causing the impression. Has anyone seen any serious research on this? I can't recall Toole making a fuss about it.
Possibilities:
- uneven frequency response, causing notes played at same loudness to sound 'jumpy' and dynamic. Used to be more common with horns than it is today.
- rolled off bass causing loss of perceived impact even at mid volumes. An ESL problem?
cheers
I think I am within my rights to ponder how much of that subjective impression is autosuggestion.
I don't exempt myself. I am yet to hear an ESL that I don't think sounds just a little lifeless. Could be imaginary. Although the one audition I most keenly anticipated was ruined by the owner playing at a volume I would call completely unengaging -- I would guess 60 dB, I kid you not -- and responded to my plea for more volume by turning it up about 3 dB. Maybe his DIY masterpieces had an Achilles' Heel that he wasn't going to show me....
To repeat: I'm not talking about playing loud. Once, playing music at home with a friend, I switched from my sat-sub to my horns (I had matched the loudness) and my friend said "not a small increase in dynamics there". We were playing at about 75 dB: he hates loud. Yet he sensed a dramatic increase in 'dynamics'. Was he imagining it? Since he made that comment, I think I hear it too, but maybe his suggestion influenced me.
If it is autosuggestion, then horn = highly dynamic, cone = middling dynamics, ESL = flat dynamics messaging has got to us all. 'Us all' in the general sense.
But if it is real, and at ear-preserving volumes, then something other than massive SPL ability is causing the impression. Has anyone seen any serious research on this? I can't recall Toole making a fuss about it.
Possibilities:
- uneven frequency response, causing notes played at same loudness to sound 'jumpy' and dynamic. Used to be more common with horns than it is today.
- rolled off bass causing loss of perceived impact even at mid volumes. An ESL problem?
cheers
Some speculation on my part, but my guess is that most ESLs can't produce the instantaneous SPLs required at high levels to faithfully recreate highly dynamic peaks.
Years ago there was the Carver story of someone trying to accurately reproduce a scissor snip and needing more than 2,400 watts to do it. Of course they were trying to sell high powered amplifiers, so it must be taken with a grain of salt, but I think the idea is still valid. While average power levels are normally quite low, instantaneous peaks can be very high.
If you go back to the comment I made earlier about the breakdown voltage of air limiting ultimate output in ESLs (other than Dayton Wright), you can work backward from that number and figure out how much audio voltage the speaker can handle without compressing the signal.
Many ESLs are inherently limited by insensitivity. If you get past that hurdle, next is going to be drive voltage limiting. The speaker may take the drive voltage without damage, but that doesn't mean it can actually produce the acoustic output required to track it.
Transformers can also be problematic at high drive levels, especially in the bass range.
I like ESLs a lot, but they do have their limits. Unless they are very large or are carefully designed to work over a limited frequency range (no bass), they are normally going to have output limits that are below those of other designs. For those that listen at lower levels with capable amplifiers, this limit is not often a problem or even noticed. I think they probably have no knowledge of this limit and value the things ESLs do well over high output.
For those that value high SPLs and massive dynamic range, most ESLs are probably unsuitable. That doesn't mean it's impossible to make one that will be satisfying , but most designs have compromised output in exchange for something else.
Years ago there was the Carver story of someone trying to accurately reproduce a scissor snip and needing more than 2,400 watts to do it. Of course they were trying to sell high powered amplifiers, so it must be taken with a grain of salt, but I think the idea is still valid. While average power levels are normally quite low, instantaneous peaks can be very high.
If you go back to the comment I made earlier about the breakdown voltage of air limiting ultimate output in ESLs (other than Dayton Wright), you can work backward from that number and figure out how much audio voltage the speaker can handle without compressing the signal.
Many ESLs are inherently limited by insensitivity. If you get past that hurdle, next is going to be drive voltage limiting. The speaker may take the drive voltage without damage, but that doesn't mean it can actually produce the acoustic output required to track it.
Transformers can also be problematic at high drive levels, especially in the bass range.
I like ESLs a lot, but they do have their limits. Unless they are very large or are carefully designed to work over a limited frequency range (no bass), they are normally going to have output limits that are below those of other designs. For those that listen at lower levels with capable amplifiers, this limit is not often a problem or even noticed. I think they probably have no knowledge of this limit and value the things ESLs do well over high output.
For those that value high SPLs and massive dynamic range, most ESLs are probably unsuitable. That doesn't mean it's impossible to make one that will be satisfying , but most designs have compromised output in exchange for something else.
I agree with mattstat. ESL do extremely well with dynamics (micro and macro), dynamic linearity, frequency response, freedom from transient artifacts (including ringing, usually), low distortion, usually have very good phase behavior. They do have ultimate SPL limits, where the dynamic range compresses and they just cannot cope with really high instantaneous SPL levels.
Also, most are dipoles, and even if a dynamic subwoofer is used, this range extends up to the midrange. Dipoles just sound different than omnidirectional radiators (like sealed boxes) in the bass/midbass/lower midrange. They don't have the same "slam" and many value that. Personally I think dipoles sound more like what I hear in the concert hall, but others disagree.
For me what ESLs do right well outweighs their shortcomings. Even the old Quad 57, set up properly in a good room (both of which are hard) sounds amazingly dynamic and just plain real as long as its limits are accepted.
Also, most are dipoles, and even if a dynamic subwoofer is used, this range extends up to the midrange. Dipoles just sound different than omnidirectional radiators (like sealed boxes) in the bass/midbass/lower midrange. They don't have the same "slam" and many value that. Personally I think dipoles sound more like what I hear in the concert hall, but others disagree.
For me what ESLs do right well outweighs their shortcomings. Even the old Quad 57, set up properly in a good room (both of which are hard) sounds amazingly dynamic and just plain real as long as its limits are accepted.
Not all ESLs are alike as has been mentioned. My experience is with B&W, KEF, and JBL. All very dynamic in the lower registers, where the Acoustats imo are lacking when placed 3-4ft. from the back wall. Too close to the floor and the panels become boomy. However they do not lack bass definition whatsoever. Placement includes gauging how far off the floor they need to be in a particular room. Acoustat lifted the original X 12inches off the floor in the Monitor series and that's about right. I have not heard as good bottom end definition with any other speaker I have ever heard; right down to the bottom, honestly. There's no muddy bass. It's all there. What's not all there is the residual extension/decay. It's rather dry down there. That's where the subs come in. Now it's complete. Okay the top is slightly rolled off so now you can bring it up to concert level comfortably without pain.
Upper dynamic slam wise, nothing comes close that I've heard. I have not heard anything as real sounding. They're awesome, really. People don't realize just how critical placement actually is with a flat panel. I mean on every plane it HAS to be spot on, no deviation. This in order to realize their dynamic capability. When it's paid attention to, that sweet spot isn't as little as it's known for.
Upper dynamic slam wise, nothing comes close that I've heard. I have not heard anything as real sounding. They're awesome, really. People don't realize just how critical placement actually is with a flat panel. I mean on every plane it HAS to be spot on, no deviation. This in order to realize their dynamic capability. When it's paid attention to, that sweet spot isn't as little as it's known for.
For me it is simply illogical to say that placement is super-critical for a dipole speaker when experts including Linkwitz say dipoles interact less with the room than other speakers.
No problem with needing to be clear of the back wall, that's obvious, but "every plane HAS to be spot on, no deviation" contradicts one of the fundamental properties of dipoles.
Oh well, something for me to mull over. And we are off topic, I suppose.
No problem with needing to be clear of the back wall, that's obvious, but "every plane HAS to be spot on, no deviation" contradicts one of the fundamental properties of dipoles.
Oh well, something for me to mull over. And we are off topic, I suppose.
I'll put words into discopete's mouth -- he'll correct me if I'm wrong -- but the placement becomes important for imaging. For bass/dipole placement it is not that critical as long as they are a few feet from the back wall and have "some" space from the side walls. The directivity of ESLs can be a challenge (Bevs and the Specta are somewhat different) on you manage the direct and reflected sounds to be balanced properly to give a reasonable image. This can be quite challenging.
Maybe it's a psycho-acoustic thing that correlates to what DrJJ says, I don't know, but I have come to recognize that unless both those panels are projecting on the exact same trajectory, everything falls off including dynamic performance. It seems to be all or nothing in terms of the difference. Obviously I'm declaring placement supercedes the fact they are dipoles. So be it. That's my experience. I care a lot about this and have done everything possible to discover if it matters. It does, a lot. If a snare drum is being imaged to the exact spot it was intended, will that not enhance it's dynamic impact? Couple that with the character of flat panels' general sensitivity per meter compared to dynamic drivers. They don't fall off with distance the same, hence the 115db at 20ft. spec for the Acoustats. To realize it, you have to be in the sweet spot much more critically.
Dipoles
I'll give a few more words about dipoles. Most consider just the bass, where when you equalize it gives you a nice flat frequency response, and the classical figure-eight radiation pattern. That's a simplification, but good enough for now.
When you go above the critical frequency, usually rolled off for bass, the frequency response gets rather ragged. I'm not sure what happens to the radiation pattern, but I'd bet that you no longer have the figure-eight pattern. You get more independent forward and backward waves that interact in an unpredictable manner.
That makes placement important.
See, for example, Linkwitz:
Electro-acoustic models
I'll give a few more words about dipoles. Most consider just the bass, where when you equalize it gives you a nice flat frequency response, and the classical figure-eight radiation pattern. That's a simplification, but good enough for now.
When you go above the critical frequency, usually rolled off for bass, the frequency response gets rather ragged. I'm not sure what happens to the radiation pattern, but I'd bet that you no longer have the figure-eight pattern. You get more independent forward and backward waves that interact in an unpredictable manner.
That makes placement important.
See, for example, Linkwitz:
Electro-acoustic models
As another point of reference, the manual for Quad 2805's (same basic design as ESL-63, 988, etc.) states that maximum output at 2 meters is 2 N/m^2, which is 100 dB.
With a stated 86 dB equivalent sensitivity (82 dB by Stereophile's estimate) and essentially a 100 watt input limit, it makes sense that some listeners find some electrostatics lacking in dynamics, especially when listening distances stretch out.
Does the dynamic speaker of Mr Linkwitz slam ?
He liked the classical concert a lot...seems his dipole bass with steef Seas bass driver are doing the job till the range of the so called impact (subjective dynamic feeling) is lying...so around the 100 hz more or less area , the upper mid bass being EQed by a LR transform with dsp
..
Question, if the room permitt it, should we have a bump around 100 to 200 hz as the class A speakers of stereophile ?
He liked the classical concert a lot...seems his dipole bass with steef Seas bass driver are doing the job till the range of the so called impact (subjective dynamic feeling) is lying...so around the 100 hz more or less area , the upper mid bass being EQed by a LR transform with dsp
..
Question, if the room permitt it, should we have a bump around 100 to 200 hz as the class A speakers of stereophile ?
And often this is in this area most room have their Helmthoz frequency...room is dictating...and patern is still 360 degrees at 200 hz
This may not answer all of your questions, but fundamentally dipole bass sounds different than monopole bass. Monopoles have much more "slam," though I think that dipole bass is more accurate. If you listen to modern electronic music, the slam of a monopole usually is attractive. It is artificial music in its production anyway. For classical music, or jazz, the dipole just sounds more real to me. It has nothing to do with frequency response, but rather how the bass energizes the room.
There is a practical lower limit to the frequency response of a dipole. Below about 30 Hz or so, a monopole is the better solution. Lower frequencies require enormous driver areas, and huge amplification power. Linkwitz came to agree with this.
This has been discussed to death in the multiway group, where dipoles are a recurring discussion topic. I'd suggest you look there for further information.
There is a practical lower limit to the frequency response of a dipole. Below about 30 Hz or so, a monopole is the better solution. Lower frequencies require enormous driver areas, and huge amplification power. Linkwitz came to agree with this.
This has been discussed to death in the multiway group, where dipoles are a recurring discussion topic. I'd suggest you look there for further information.
What a great discussion. I have always loved electrostats especially on Jazz, Classical, and Acoustic music but for the life of me could not get them to sound good on vintage progressive rock albums. It has been a frustrating experience. I've got to think that the compressed nature of the recordings just do not sound good coming out of the planar speakers. My guess there is not a solution to this situation other than adding woofers / subwoofers. I have Soundlab speakers with a planar sub. The planar sub is a stereo sub (B1S divided in R/L halfs). The sub puts out prodigious amount of bass and sounds great with the aforementioned music genres. I have played around with different crossover frequencies. Dr. West at Soundlab suggested 500hz to completely off load the bass from my A1s. Although I get an element of "slam" it still does not make "rock / prog rock" music come alive like horn / 15" woofer speakers that I have heard.
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A lot of good thinking in the post about peaks. Sharpest peaks are in girls' choirs singing Brahms' Lullaby (no kidding, hard to have enough tweeter power).
But - and first of all - you won't find outstanding peaks on recordings unless you make 'em yourself and with very low average level or special commercial releases.
Next, if there's any technology that can blast a quick peak, it's got to be plasma... OK, ESLs are second best.
We've been living with compressed audio sources since recording began, with softer and smarter compression showing up in later decades. So hard to say what we would hear if we could play Mahler back at home. (Footnote: homes have their own S/N limitations too.)
And now a word about Gwho playing great old rock 'n roll favourites: they might indeed sound like crap on good systems and maybe that is the charm they hold when played on awful systems.
Historically speaking, as I am entitled to do, the ancient debate about east-coast (analytic and accurate) versus west-coast sound (coloured, subjective, and thrilling) goes to the heart of it. Many of us took an oath long ago to only endorse accurate sound and let the output sound as it will. Even if old rock and roll vinyl pressings just doesn't sound quite right.
B.
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Don't laugh, reproducing MacCartney bass guitar is not that easy at home... indeed an old VOT or Onkens did that well...
It's a mystery for me than editors don't make two sorts of reccording , the compressed we know and a ten time expensive non compressed ones...enough audiophiles in the world for good business imho.
It's a mystery for me than editors don't make two sorts of reccording , the compressed we know and a ten time expensive non compressed ones...enough audiophiles in the world for good business imho.
To me, 500 Hz is midrange -- the note used to tune orchestras, for example, is A440. To me 500 Hz just seems too high -- I'd think that 200 or maybe 300 Hz would do it. But you do seem to have a good match for the radiation pattern between the main and "woofer" speakers, so you probably have more latitude than most of us.
Still, at 500 Hz the wavelength is about 2 feet, so I'd worry about interference effects. At 200 Hz, the wavelength is about 5 feet, which should make the transition a lot smoother.
Nice system, BTW.