24"x48" stator at 3/32nd gap....

[fperra]

Any comments on his 3/32" spacing vs. 1/16"? Advantage is less capacitance to the amp, disadvantage, sacrifice efficiency.

 

[moray james]

Acoustat`s use about 1/16 of an inch spacers so if you want greater efficiency you will need to go for a thinner spacer and less bandwidth. Increasing your static charge will help, most stock Acoustat`s run at about 3K (more or less) and can usually stand about 5 Kv perhaps 6Kv depending upon humidity but that`s pushing it especially if they are old and breaking down and hey they are all old now. It`s swings and round abouts as the British say and you always have to give to get, it`s universal given that `lunch is never free`. Of course if you slap a horn onto a stat which has been done you wont require much peak to peak.
If you want to go multi way look to the Quad ESL57 as your inspiration and if you want to go full range the Acoustat model is the one to follow. Personally I think an Acoustat style line source built as a hybrid will get the best for the least. That`s just me. Going further outside the box I think a Unity style horn with stat hi and mid drivers coud be impressive. Right now I am enjoying some upgraded Klipsch speakers, Forte ll and KLF20 which match the stats in low distortion but have real world dynamics and superb efficiency. Horns stats and ribbons are the only way to go but you have to pick your poison. Best regards Moray James.

 

[geraldfryjr]

My plan is to have everything in a box of course,But this what it looked like when I first got them running again last year.
As you can see how the Bias supply was sprawled across my desk.
The control and driver circuit is on the solderless breadboard feeding a little torriod transformer and then the voltage multiplier string.
The variable voltage in this case came from my bench supply

http://www.diyaudio.com/forums/planars-exotics/166039-esls-planars-etc-me.html#post2181069

Here is the link about the corroded copper charge ring.

http://www.diyaudio.com/forums/plan...on-problem-copper-strips-esl.html#post2134245

This is a great thread as we started getting into transformer design towards the end.

http://www.diyaudio.com/forums/plan...nstruct-cube-louver-acoustat.html#post2142851

I used CA to glue the stator to the egg crate lighting material and the frames together.
Epoxy to glue the mylar to the frames as it seems to work the best for mylar,Although it is quite messy and a PIA.
I have tried everthing so far except poly glue as it foames up as it cures and doesn't seem to bond to plastics very well in some cases.

Some have had good luck using a brush on type contact cement I have not tried this.

Don't waste your time with the spray on types as they just make a mess of things, and,Generaly aren't secure enough to hold the tension of a larger panel.
Not to mention the thickness consistency or smoothness of the the glue as it comes out of the can is terrible.

more pictures,

http://www.diyaudio.com/forums/planars-exotics/162127-different-ideas-esl-panels.html#post2111911

http://www.diyaudio.com/forums/planars-exotics/162127-different-ideas-esl-panels-3.html#post2129441

The Quadstacked cores I got down to the 15hz range with the setup although it had to much transformer capacitance and caused problems for the amplifier at the higher frequency's,

http://www.diyaudio.com/forums/planars-exotics/162127-different-ideas-esl-panels-3.html#post2133053

Bias supply arcs,

http://www.diyaudio.com/forums/planars-exotics/162127-different-ideas-esl-panels-5.html#post2151682

Here are the close up pictures of my bias supply,

http://www.diyaudio.com/forums/plan...t-panel-angles-8-vs-9-panels.html#post2170344

jer

 

[Mike Beck]

Acoustat`s use about 1/16 of an inch spacers so if you want greater efficiency you will need to go for a thinner spacer and less bandwidth.... Best regards Moray James.

Acoustat actual D/S was 2.5mm (1/10 in). Solvent welding caused the wires to sink into the grid slightly providing the extra gap.

 

[bolserst]

Acoustat actual D/S was 2.5mm (1/10 in). Solvent welding caused the wires to sink into the grid slightly providing the extra gap.

This value agrees pretty well with the measurements I took of two different Acoustat models(1+1 and Spectra 11) which were 0.09".
http://www.diyaudio.com/forums/planars-exotics/183168-acoustat-answer-man-here-8.html#post2493836

Does anybody know if Acoustat had a way of controlling the amount by which the wire would sink into the grid?
Seems like it would be important so get consistent results.

 

[moray james]

are you both measuring the distance between the surface of the dielectric and the diaphragm? I measured between the top of the styrene holding the stator wire down to the louvre and the diaphragm as that is the physical limit the diaphragm has till it hits the stator. This had to be averaged out but was fairly consistant on the panels I measured. Best regards Moray James.

 

[bolserst]

are you both measuring the distance between the surface of the dielectric and the diaphragm?

We are measuring the distance between the uncharged diaphragm at rest, and the outer surface of the PVC stator wires.

Looking at the attached pic:

d2 = the spacer thickness = distance between diaphragm and the surface of the louver.
d1 = D/S spacing = distance diaphragm can move before hitting the stator wires.

Since the wires are glued to the louver, d1 = d2 - OD of wire.

I measured:
d2 = 0.15" & OD of wire = 0.08"
So, if wires were glued to the surface of the louver, D/S would be 0.07" = 0.15 - 0.08

But, the wires melt down into the louver a bit.
With dsink = distance wires sink into the louver:

D/S = (d2 + dsink) - ODwire = 0.09"

 

[moray james]

Yes the actual physical distance that the diaphragm can traver till it is going to hit the stator (or in actual fact the styrene on top of the insulated wire) is D1 minus the thickness of the styrene used to encapsulate the PVC stator wire to the louvre. Best regards Moray James.

 

[arend-jan]

@bolserst

That picture looks like it came from an interesting context...

 

[bolserst]

@bolserst

That picture looks like it came from an interesting context...

Should have mentioned, the figure was taken from the Acoustat White Paper.
I had added the dimensions (d1, d2) to the figure in an old post and just grabbed it for use here.
http://www.diyaudio.com/forums/plan...ruct-cube-louver-acoustat-14.html#post2183450


More information and links to the paper can be found in the following post:
http://www.diyaudio.com/forums/plan...truct-cube-louver-acoustat-7.html#post2154621

 

[joojoo1234]

My metal is on its way - got a 22 gauge and a 20 gauge both steel. 51 and 57 open space... can't remember the holes... seem no agreement except avoid the tunnel effect of thick steel and small holes. I avoided this. Have my mylar. The 2 micron stuff does not seem to stretch but it would be hard for me to tell if it is tensilized or not by cutting a foot off and stretching it. It breaks easily if it is connected poorly and is surprising in its strength if it is connected properly if you know what I mean. I am doing a very low tweeter design now. I want my amp to drive it easier. I am going to ask a difficult question... How low would a tweeter have to be crossed to notice that it is an electrostatic? How low to get the electrostatic character predominant in a speakers character????? I know ML crosses at 450? I was thinking of crossing at 850-1000... is that low enough to give a change of character to operatic vocals via their harmonics and such (for example)?
THANKS GUYS FOR ALL THE HELP!

 

[joojoo1234]

659 is to my ears at the a piano a good cross area and still get this electrostatic character.
Guessing of course. 20x10 roughly panel curved is what I am shooting for for the extended tweeter.

 

[chinsettawong]

You want to crossover at much lower than that. As for me, I love running mine full range.

 

[joojoo1234]

Metal arrived. I also have some red insulating paint... around 2400kv. I am deciding on a design and reading on woofers and such. Not doing a full range and simply deciding where to cross as well as a physical design... things b moving!