Are electrostats any good for rock and roll?

Man speaker decisions are hard.
Earlier this evening I heard some Innersound Eros MkIII speakers powered by their electronic crossover amp and another Innersound ESL 300 on top, along with the ARC CD3 & ARC pre amp. Cabling by Luminous Audio & ESL 300 PC was a Chris V Flavor 2.

This was the best electrostatic type speaker I've ever heard & ranks right up there with the best of speakers. There was nothing lacking in the bass region & of course the rest of the freq. range was splendid. On rock they were very fast & I could detect no compromises. They can also play LOUD. On complex passages the sound didn't get confused & everything I heard was coherent. In a short 2 hr. listening session I heard enough to want these speakers. Can't afford them right now but maybe if I pawn my wife's diamond I could, as she never wears it anyway.
To play loudly, you have to move a lot of air. To produce low bass, you have to move a lot of air. Most E-stat's by themselves lack both the surface area and the excursion necessary to do either of the above. The only E-stat's that i know of that "might" be able to do this, and this will vary depending on room size, spl levels required and amount of bass that you want, "might be" the big Soundlab's. I have my own "personal doubts" about that though.

As such, most designers resort to "hybrid's" i.e. E-stat mids and tweeters with dynamic ( cone ) woofers. In order for the cones to blend with the e-stat's, they must be very fast, low Q at resonance and low Qms. The result of using a driver / alignment like this is that you have minimal overshoot and ringing and the driver is both very well damped and easily controlled at or near resonance. Any type of poor transient response or "tubbiness" will stick out like a sore thumb. Obviously, special attention to the crossover is required or all the hard work selecting drivers and cabinet design will go out the window due to improper "blending" of the drivers where the two different types of radiators overlap each other.

Even if one can get all of this "right", these types of speakers typically have limited dispersion patterns and produce a pretty narrow ( i.e. "beamy" ) sweet-spot. Some e-stat's have been characterized as having a sweet-spot that works well so long as you "hold your head in a vice" i.e. not move it around at all.

Having said all of that, i would say that mass produced E-stat's are not really "ideal" rock and roll speakers. Yes, many of them will "rock", but most won't "jam". I know that others that own E-stat's may want to crucify me for saying that, but this is strictly my personal opinion. The commercial designs that i've heard simply will NOT play loud enough to produce "sustained concert level" spl's in a medium to large sized room. If you try to do something like this, the mylar is either going to stretch badly and / or you'll arc the panels. You can get around this somewhat by going to a hybrid design, but i've yet to hear a hybrid that really worked "well" in terms of blending the drivers together at various spl levels. Most hybrids work well together in a specific spl range but the differences in driver characteristics become more apparent as you try to vary the output levels quite a bit. This is due to the fact that cones require excursion to produce output due to their limited surface area while e-stat's require surface area to produce output since they lack excursion. Finding a good blend between the two is VERY tough. Believe me, i know as that is what i'm "trying" to do with my main system. Sean

You're talking a lot of theory and generalities, which says to me that you don't have specific experience with the InnerSound Eros Mk-III that Driver raved about above.

So just FYI, the Eros can play VERY LOUD without strain (I'm sure it's pretty clean up to 115 dB or so). Roger Sanders tests the panels by playing them for extended periods of time at SPLs exceeding 100 dB for an individual panel. And the panels produce about 98 dB at one watt, so they are robust AND efficient. The can reproduce kilowatt peaks without stretching the mylar or melting. So, yeah, they pretty much can reproduce a symphony orchestra playing full tilt in mid- and large-size rooms; and I've heard them do it.

Yes, they are beamy (very!), and it seems that the bass and the mids and highs blend properly at only one distance from the speakers and that is because the ESL line source maintains its loudness further out from its diaphragm than the point source woofer which falls off in dBs more rapidly as the distance to the listener increases.

I owned a set of the Mk-IIs, which are similar, and was sorry to let them go due to a move across country. Sean, if the ESLs you are trying to build perform half as good as the Eros, then I'd say you are doing well.

Now, for the first time in years, I'm using a dynamic speaker as my reference -- the Audio Physic Virgo II. My new room is smaller than my previous basement listening room and the Virgos seem to fit and work well in the smaller space. I still miss some of the dynamics and scale that the Eros presented so well, but the Virgos are not too far off the mark and are endearing in other ways. Certainly they have a larger sweet spot. I use them with a subwoofer, just as I had done with the Eros and that seems to fill in the last half octave of very low bass nicely.

Perhaps one day I'll return to E-stats, but from what I understand, the ultra-low humidity here in AZ is not the best environment for ESL panels.

Driver, if you can deal with the Eros' narrow sweet spot then they may be just the speaker for you.
Hey Plato, I get enough grief from the wife about the VR4 GenIII's which grace her living room & I think with the Eros she would make life difficult for me, although her main complaint is they're black. Maybe I could sneak a pair in & she would only notice the black ones were gone?

Yes they are, and so are ribbons. The problem is not so much in the type of music...but the quality of the recordings. A great deal of rock recordings were recorded (lots of compression) to sound loud only. These types of speakers are not forgiving of poor recording quality, they will sound very, very good with rock recordings of high quality. The other problem is that most rock music has a foundation which is built on bass, cost of full range e-stats or ribbons can be high and a good sub that will blend with them is also a cost. If cost is of no matter to you and most of your rock is of higher quality recordings...you should be very happy. IMHO

i owned the sound lab U1s and ml prodigys, and the list goes on. if i liked to rock and roll then i would not buy stats. i agree with sean in hybrids never seem to blend. the the U1s give plenty of volume and bass but macro dynamics never seemed to sound right. with most other music including big dynamic classical the big stats are very hard to beat. the big stats are only for the person who does not care about space. they would certinly be on my short list. i finally picked up the nova utopias. they have stats beat on almost every level. the big labs still have spooky midrange.
Driver, I think the Eros is coming in some other finishes now besides the black, which could be the key to sneaking them past your wife. However, they are on the large side and as such would be hard to conceal.

I've taken my system to a spare bedroom because even though the living room is larger and has terrific acoustics my wife is just too critical of how things look in the LR. God forbid someone were to pay a visit and be forced to see unsightly speaker cables or interconnects -- and those outboard power supplies, just hideous!

So rather than having to pass her continual scrutiny I confine my gear to a somewhat smaller room where I can pretty much do what I like and not be concerned about how tidy things look or don't look. Women!

That said, I'm still going to try to slowly sneak some decent gear into our modest living room system... My wife likes the look of my Michell Gyro SE and luckily there is some really gorgeous equipment available. But I may need to find a nice remote controlled integrated amp and stick with the one-box CD player (got to minimize the number of boxes and the associated wiring)... ;)

Best of Luck to you!
The above mentioned electrostats are very good. Electrostats are very unique and you will have lots of fun explaining them to most visitors to your home. i own a pair of Acoustat X self-powered electrostats and I like them very much.

I will be making some changes in the next year and I won't be buying speakers until I test some more electrostats.
I can testify that the Eros Mk 3 will play very loudly without strain, in fact for me they even tend to be rather easy on the ear. The bass is fantastic and so is the woofer to panel blend. The only real problem I have with them is if you aren't locked into the sweet spot they tend to sound just slightly dull, like if you are leaning back in the couch kinda slouching or even laying down, they will make you think they aren't so special. When you get right in the sweet spot then magic happens.

I got my pair in all silver, side rails and everything with the matching electronics. My wife too was not so keen on having a big system in the living room, but she really likes the looks of the Eros in Silver and most people who visit comment favorably on their appearance.
I have to assume that Roger Sanders has come a LONG way on E-stat design. I am quite familiar with his work and even have his book about "homebrew E-stat's", which is probably quite a bit out-dated. The fact that he is the one given credit for "inventing" the curved panel design and then threw all of that time and effort away for the flat panel design that he is currently marketing tells me that he is a pretty open minded individual. Most folks that would have had that much time and effort ( not to mention ego ) into such a thing would have a hard time laying that down and admitting that there are better methods out there. I'll have to check into these and see what i can find. Sean