ESL enclosures

Has anybody ever seen an enclosed ESL?

I have never seen this subject tackled or discussed, i have never even heard of an enclosed ESL.

Has anyone ever seen an enclosed ESL? Anybody know why ESL's have no enclosure?

Ive dont alot of searching, but i have yet to find anything that addresses this topic.

I see that when using dynamic drivers, the point of the enclosure is to trap the rear radiating sound waves to prevent cancellation of the lower frequencys. Then there are loudspeakers with dynamic drivers like the AAlon Lotus Elite which only uses a baffle for the mids and highs, but no enclosure.

just about everything i have read will state the point that without the enclosure the non-directional frequencys cancel eachother out, thus resulting in the lack of bass.

Could placing an ESL in an enclosure extend the lower frequencys of the driver as in dynamic? Or does the resulting damping interfere with the ESL's preformance?

From the construction techniques used for ESL drivers, it should be difficult to ensure the box is air tight with the driver installed.

When it boils down to it, the actual driver motion of an ESL is no different than that of a dynamic driver. The membane vibrates forwards and backwards just as a dynamic drivers cone. Its just the process of causing the movement that really differs.

Any takers on this one?
I think that Mart over at AA has done this with Maggies, but i'm not sure. Sean
Sean, I must say when it comes to answering a semi technical question regarding audio stuff, That without a doubt, was the shortest answer I have ever seen from you.

Didn't Genesis or Infinity do something like this. Of course their drivers weren't typical ESL's.
Harold Beveridge did it years ago with his acoustic lens approach...

With a sealed enclosure its seems logical to assume that it may damage the membrane- I don't think its designed to deal with pressure. I think using lens' would work best because your, your diffusing the rear wave. I know some guys like "wings" on there speakers but that's the older days(long before guys like us were around Slappy :), also it seems to be popular with guys in smaller rooms- helps channel seperation.
The whole point of planar drivers is to get rid of the box sound. The LF cancellation effect has been exaggerated.
Eldartford, the "LF cancellation effect" is very real and some individuals may have room and placement restriction issues. There is more to planar drivers than elimination of "box sound". Amongst other things, many are enamoured by the apparent speed and line source presentation afforded by panels.
In the 70s there was a SuperQuad, which was ESLs just sitting inside an enclosure with Kef 139s woofers on one side of the enclosure. I do not think, however, that this is what you are talking about. Enclosing Quads into a sealed compartment would cut their efficiency in half I suspect.
Unsound...Agreed that LF cancellation is a real phenomna: I just said that, as a problem, it's exaggerated. An ordinary cone driver in a open flat baffle suffers greatly from LF cancellation, but Magnepan (for example) has tweeked up the membrane with tension and weights so as to achieve flat response comparable to box speakers.
Kinda seems like this is an audio area not completly explored.

I was thinking about that, i know that DYI recipes for ESL's tell to use mylar or even saran wrap. Obviously not very thick and not *too* durable.
I guess the best solution would be a membrane that is light but with increased rigity.

I was under the impression that the large surface area and stonger control of the driver is what made ESL's so desireable. With a grill stator delivering uniform pull to the entire membrane it increases the clarity over the normal Dynamic driver which is basically a cone attached to a piston and is more inclined to suffer from distortion. I know that the whole "Boxy sound" can be greatly diminished by not using a box, but rather smooth curved surfaces.

Im looking for a niche to get in with speaker construction, trying to find idea's that people will be attracted to.
I think full range ESL's that can reach down to 40hz would be rather appealing. Im sure there are some ESL owners who can get a full range out of thier speakers, but the lack of bass is something commonly spoke of.

Another niche i was thinking of is finding a way to make smeakers that are intended to be up against the wall that dont suffer from that type of placement.

I figure that there are a billion companys out there, if i want to succeed i gotta do something different.
Slappy, full range ESLs that extend well below 40 Hz with authority are available. You could use the technology behind them for your own use at the least. Dr. Roger West of Sound Lab has a patent on the distributed bass resonance principle employed in his speakers which gives profound bass response. Perhaps there are other approaches that could work.


Yes, an electrostatic that was enclosed was the Dayton-
Wright speaker, made in Canada by Mike Dayton-Wright back
in the Seventies. It contained a gas inside the envelope
containing the electrostatic drivers and had a good sound
in the midrange and midbass, but lacked extension on the
highs. It was problematic in the first designs, but later
iterations seemed to work well. They were not my cup of
tea as a preferred speaker. ...Carl