Electrostatic Speakers

Weaknesses: dipolar dispersion pattern isn't capable of the most accurate imaging/pinpoint. You also have to sit 2.5 to 3 times the panel heigth back (this may or may not be a weakness). Obviously, narrower dispersion as frequency increases: beaming. (can be like a giant pair of headphones in the room) More generally (so not always true): ampl. v. freq. resp. tend to not be very flat even on axis(+/-4db)(off-axis was already accounted for), tend to lack good damping/restoring forces so the waterfalls/cumulative spectral decay's can have alot of overhang. Ideally, more specifically, they wouldn't have the impedence matching transformer so they could be directly driven with an output transformerless tube amp--so most commercial versions are already compromised if your driving off a "regular" amp and its got the impedence matching transformer. And under those conditions they are generally a "tough" load; and as impedence drops the amplifier's distortion goes up (although small). Also, there can be reflections off the panel's edges--depends on how the manufacturer may or may not have tried to deal with that: sometimes a foam strip along edge. Also, I believe general placement is more done by ear, since most of the speaker placement programs and general rules-of-thumb don't work with dipolars. I've also seen units designed to diffuse/diffract the backwave from the esl. I don't know if their benefits justify the price, or improve performance enough to justify them as being: essential components. Lastly, and esl owners would know this, I don't know if some type of power conditioning is truly beneficial at times since the speakers do have to be plugged into polarize the panel: hence a dirty signal may do some damage.

I must say, these are two of the most informative and knowledgeable responses I have ever received from this page. You guys seem to really know what you are talking about. Thanks! Incidently, if I purchased the soundlabs, I would be running them with a 75 Watt OTL. I also listen in a very small room, since paying low rent is the only way I can afford these high priced electronics.

Haydn_josef- I wouldn't even think of trying to power soundlabs with a 75 watt otl, the impedance swings would be VERY unpleasant-which is one of the weaknesses of electrostats. You most likely would get the best results with a speaker that has a nominal impedance of 8 ohms and fairly stable, ie it doesn't have huge swings like electrostats often do. Unfortunatly otl's and electrostats don't mate up well, something along the line of Talon, Piega or Kharma would do much more justice to your amp-although all of the fore mentioned speakers are cone type drivers(and are just a few of my favorites with OTL's-there are many more that I am sure will work good) or big clunky boxes-though I like my big clunky boxes :)
btw great posts so far; Sdcambell and Ezmerelda1
~Tim

I considered Martin Logans for a long time. The treble was magical but one problem I found with them is they didnt like to go very loud. I was told by the salesman that the reason for this is that the tweeters compress and distort when pushed to hard.

I have always regrtted though that I never owned a pair of electrostatic speakers. Maybe its a good excuse for a second system.

I've owned electrostats for almost 15 years, starting with Acoustats, Martin Logans (3 models), and finally large AudioStatics. All of these speakers were nothing short of amazing with OTLs. In fact, I would suggest that OTLs are the only way to get the absolute best from an esl. It is true that I had the benefit of 140 watt OTL monoblocks. Given the fact that your 75 watt OTLs would only be about 3 dB lower in maximum spl, I would still suggest that you try them. You may find that they are more than up to the task. Yes, this system may give up some dynamics compared to better cone systems, but the midrange/top-end can be a revelation. Particularly in a smaller room, the power issue becomes even less of a concern.
As is always the case, auditioning a speaker with your amp is certainly the best way to dispel all concerns. Good luck in your audio search.