Help with DIY electrostat's

[ak_47_boy]

I would like a build a test DIY eletrostatic speaker out of intrest. What would be the best material to make the stators out of? Perforated aluminum, brass, carbon steel, galvinised, plane steel, or stainless steel. Also, can i have just one big pannel for high, mid, and low? Or should i have seperate pannels for each? How thick should the stators be? How big should the holes be? How far aprt should te holes be? Can i order it in a roll and flaten it?

http://www.mcnichols.com/products/pe...s/sizes_p4.gif
http://www.mcnichols.com/products/pe...s/sizes_p5.gif

[v-bro]

In this link you have the "Spider ESL" (By Tim Weert), it is a full-range electrostat à la QUAD ESL-63, they used adapted stators in ring shapes to create higher freqs more from the middle of the membrane:
http://esl.hifi.nl/project04.htm

On the old photo you can see my QUAD ESL-57 mid-treble panels (I got rid of the bass panels, replaced them for a sub...) I still have 3 other panels I stripped for parts, could do some more investigating for you...

More interesting links:
http://sound.westhost.com/project105.htm
http://www.sacdmods.com/ESL/index.htm
http://amasci.com/esloud/eslhwto.html

[I_Forgot]

The best material for a test speaker is whatever is readily available to you easily/cheaply. The material doesn't matter as long as it is electrically conductive, i.e. metal. You will not get better performance by buying exotic materials or by having materials plated with gold or platinum. Steel is heavier than aluminum, so you may want to go with aluminum, but it costs more.

Of course, you can make wire stators, but that's a lot of extra effort that may or may not be worth the trouble. The difference between wire and perforated stators is mainly cosmetic. Another way to go is to attach window screen to a rigid structure such as a fluorescent lamp grid. That can be a very inexpensive way to go.

You can use separate panels for different frequency ranges, but that would be ignoring one of the best characteristics of ESLs- wide bandwidth. If you are going to break up the audio band into multiple parts and use crossovers you may as well use cone type drivers and save yourself the expense and trouble of making ESLs. For a test driver I think you should start with a medium size panel and drive it full-range to see what it sounds like. Later, when you start throwing in crossovers, you'll know what you gained and what you gave up.

Unless you have a sheet metal shop, don't expect to be able to flatten rolled up sheet metal. Get your material cut to size and flattened.

Hole sizes and spacing really aren't critical, but you will get maximum efficiency from the speaker by maximizing % hole area. As a practical matter, commonly available perforated sheet with staggered hole pattern can get up to about 60% open area. Hole size between 1/8 and 1/4" (3-6mm) is fine.

If you have a source of DC bias and a transformer to step up the audio voltage, almost anything you throw together for a driver will make sound. It is hard to make an ESL that doesn't work because it is so simple.

I_F

[ak_47_boy]

I never heard of useing wire before as a stator. Good idea. I can see many hundreds of hours going into it.
Is there any specific way the wire should be wound into the stator or is that spider like that only for looks? Is the mylar one big piece or is it divided up for high and mid range inside the esl?

edit: The last site talks about parts that are needed. It says use a 15-20watt output transformer. Would i have to use a bigger one if i wanted to make a bigger pannel? or would a little one work fine?

[ak_47_boy]

What guage of wire should i be looking at?

[bear]

Fwiw, there are several threads that are pretty recent that go through most of the issues in building an ESL... if you take the time to read them through most of your questions will be answered!

Then you can get at the details and some of the variations in methods and materials...

_-_-bear

[stokessd]

Originally posted by bear
Fwiw, there are several threads that are pretty recent that go through most of the issues in building an ESL... if you take the time to read them through most of your questions will be answered!

Then you can get at the details and some of the variations in methods and materials...

_-_-bear

I second this advise. After building my own ESL's and then reading the ESL construction threads on this site, I was amazed at the cleaver solutions to some vexing stator construction problems. If you are serious about doing wire stators, spend some time reading the fabrication threads...Good stuff.

Inother words, there are some smart cookies here.

Sheldon

[ak_47_boy]

My eyes are burning from reading at the moment, i had know idea there was this much good stuff. Its all just hard to find though.
I have not found anything yet regarding my transformer question and i have not have the term "output tranformer" even used. Is there some other type that people are useing?
I have seen 32-20awg wire used, is smaller better?
I think i have decided on a 40% open stator. ya?
I think i want to use magnet wire. ya?

I have also read a few threads on voltages but i don't exactly understand. Correct me if i am wrong: The mylar is charged with 1kv-5kv. The audio is steped up to the same voltage as the stator is.

[v-bro]

Originally posted by ak_47_boy

I have also read a few threads on voltages but i don't exactly understand. Correct me if i am wrong: The mylar is charged with 1kv-5kv. The audio is steped up to the same voltage as the stator is.

You are correct.

As for the wire, I think it won't matter much.

As for the magnet wire, I don't know, if it's conductive I guess it's okay.

As for the output transformer, I think that they mean the power it can handle from the amp. In this link http://sound.westhost.com/project1053.htm they use very common 100V speaker line transformers as step-up transformers. A relatively cheap way to go, there's also a "more power" option....

[moray james]

http://www.diyhifi.org/forums/viewtopic.php?t=305

http://www.diyhifi.org/forums/viewtopic.php?t=300