ESL - Where does one start???

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Hello!!

Well one of my 2005 resolutions is to build some DIY ESL speakers... but I don't have a clue where to start!! My base knowledge is 0 on ESLs... Are there any books on the matter? And where do I get the parts? Of course, the best thing would be to be able to buy a kit with all the necessary parts and to asemble them, if such a thing exists.

And for people who have already done some: how much did it cost you in parts and how much time did you spend on the project?


Thanks for your inputs :)
 
There are a lot of resources on the web- a little searching will turn them up. Roger Sanders's book is a reasonably good introduction to the physical process of making esl cells. Much of the content (and a lot of other stuff) appeared in Speaker Builder and Audio Amateur magazines, back copies of which can be sourced from AudioXpress.


To really understand the theory, read the patents by Walker and Baxandall.
 
hey thanks everyone!! I'm currently in the process of checking those links/ books out :)

Now can anyone tell me of their personal experiences? Like how much time did it take to complete the project, how much did it cost, do they consider it worth it or would it be better to spend a little extra and buy second hand, would they do it again...?

Also, by searching around the web I got the impression that there's a ESL kit out there called NSS 0.3a... but I can't find it for sale anywhere!! Does it still exist or did the company go bust? And are there any similar kits around?
 
have a look to
http://www.audiocircuit.com/index.php
click "Enter The Audio Circuit "
select "Elektrostatic Loudspeakers" ->
"Do It Yourself" ->
"Projects"

Wulf Wulfhenkel has build his hybride speakers for about 400.-EUR.

Currently i am working on a second hand Audiostatic ES100. With a lot of help from Calvin i am sure, that this speakers will work in 2 weeks.

(sorry for my english)
 
To build or not to build...

Hi folks
...and highly respected disciple :D

well, building an ESL can be done in just 1/4 of an hour, but building a good ESL can take You Years and cost dozens of sleepless nights ;)

The already named sources will provide You with a good knowlegde base (Wagner, Fikier, Sanders, ESL-circuit), though all of them tackle some important questions rather too simple for my taste, which can lead to unsufficient efficiency and/or an unsafe -possibly lethal- construction. Another good source -though read with care- are patents. You can easily download them. Just search for ´electrostatics´ and similar.

Costs depend on the chosen concept, the chosen material and what You name cost, i.e. working time or nerves. :cool:
The later left aside there are two basic construction concepts.
One using perforated metal sheets for the stators, and another one choosing wire or rods. The materials cost is a bit higher for the metal sheets, but the construction is far easier and far less time consuming and a success is imo a bit more probable. But wire stators are less prone to beeing/becoming unsafe than sheet metal unless You find a proper insulating coating process. I´d opt for having sheet metal coated by an experienced professional coater (electrostatic spray-coating rather does not(!) do the job.)
As a startup-tip: Don´t try to built a full-range ESL as first project.
Keep to an hybrid with an mid-high-ESL.

More Infos by PN if You want.

jap
Calvin

ps: in the Sanders Cookbook-link there are pages 66-75 missing.
Is there another Web-source for these pages?
 
Hi,

Simon, I started the same way Years ago ;)
And though the result was really much better than I had expected, I now know, what lacked. The problem with ESLs is, that they are so far superior to dynamic drivers (in the mid-highs) that even quite "bad" ESLs sound much better. But having a really good panel the differences are breathtaking. One of my prime design-goals is efficiency. Like the dynamic fraction, ESLs sound much more lively and dynamic when efficiency is high. Therefore You have to get rid of the imo totally wrong fullrange thinking. Bass is the only region where dynamic drivers give better results than ESLs (when it is done properly), build much more compact and where You get the least problems with crossing over. As soon as You shift the working range of the ESL in areas where it doesn´t need to move (basically above 100Hz) the sound becomes cleaner. But the really great advantages are:
-less D/s which risens the efficiency significantly
-lower voltages, polarising- and more important signal-voltage
-lower step-up-ratio, improving bandwidth, and dynamics as well as headroom and/or allows for simpler or cheaper construction

One of the biggest mistakes that a DIYer can make is to think that a lot of D/s-spacing is of any use. It kills dynamics, it costs efficiency, costs bandwidth, costs safety! Build Your ESL with a as small as needed (+ a little reserve for tolerances) D/s-spacing. As a rule of thumb. A panel with 0.3m², working from 200Hz on needs just 1.0mm and can give efficiencies of up to 90dB/2.83V/m with an ratio of 1:40 (depending on the polarizing voltage)
If You want to extend the frequency range down to 150Hz a D/s up to 1.5mm is useful (I´d opt for more area than more D/s).
At 100Hz, 2.0mm and an area of min. 0.6m².
This way I build Panels with efficiencies around 100dB!! Imagine the outstanding resolution of an ESL partnered with the lively and highly dynamic sound of a big Horn!

jap
Calvin
 
cost

Hi,

it´s quite difficult to give numbers as long as certain conceptual points have not been cleared.

e.G. Wire Stators. If You try to build a big one You might use ordinary cheap PVC-coated wire for home installation. It´s labeled H07-VU. But You need a high polarizing Voltage and high signal voltage, which means You have to buy a very good and costly audio tranny (the transformation ratio should be around 1:100). Plastics for the Spacers are easy to get and very cheap too. Leaves You with the cost for a piece of diaphragm amd glue.
building smaller ones You can work with magnet-wire or Kynar-insulated wire which is more costly than PVC-wires, but gives higher efficiency. But watch out how much meter of wire a pair of panels really needs (can be several hundrets!).

Building perforated metal sheet stator the cost for the sheets and their insulation is relatively high. The polarizing voltage is lower (the power-supply probabely a little bit cheaper). Because You need less signal-voltage the transformer ratio can be lower and the panel may even work with standard off the shelf toroidal trannies (which reduces cost substantially, because the trannies are most often the costliest parts). Using plastic spacers the cost is low, using the 3M foam-tapes will cost more.

You can build ESLs for just a few Bucks or for thousends.
Best is to write down a materials List and calculate different possibilites. Start with known commercial ESLs. Try to figure out what they are made from and what it would cost You to copy such a thing. Ask Your local metal/plastic dealers, DIY-shops or internet to get Your numbers straight. Ask in Forums about construction/material-details etc etc. You´ll quickly see what Your favourite concept could cost You.
But no one can tell You the cost like "And the solution is........... 13!" :xeye:

so 200, or 500 or 1.000 are the correct numbers.
Modding/repairing a existing panel could be done without deeper knowledge about materials and theory. Building a panel from scratch You really have to get involved with the matter.
So You have to decide, how far You want to go and how much engagement You are willing to spend. Do you want to be an expert, or is the highly specialized user Your thing?

jap
Calvin
 
Hi all,

I'm currently building my first pair of ESL's. I'm finishing the panels and then I still have to do the electronics and the support frame.

Some thoughts:

* I built wire-frame stators, and it took A LOT of time!!!... I think if I ever build another pair, I'll do perforated metal stators. They'll be a bit more expensive, but they can be built in MUCH less time.

* Cost: In total the pair of speakers will have cost me about 800...900 Euros. But I had to buy some new tools as well, and I used expensive audio transformers (because it's a full range design). So I guess without the transformers and tools it will have cost me about 300...350 Euros

* I had some trouble finding certain parts or materials, e.g. adhesive copper foil. I found that sourcing all the necessary materials was the most frustrating about this project.

* Build time: several months' weekends work. Often you can only do a little work and then the paint or glue has to dry so you have to wait a whole day, so sometimes progress is very slow...

When my speakers are finished (still plenty of work to do ...), I'll post some text & photos on my homepage.

Happy building,
kenneth
 
Hi all,

I'm currently building my first pair of ESL's. I'm finishing the panels and then I still have to do the electronics and the support frame.

Some thoughts:

* I built wire-frame stators, and it took A LOT of time!!!... I think if I ever build another pair, I'll do perforated metal stators. They'll be a bit more expensive, but they can be built in MUCH less time.

* Cost: In total the pair of speakers will have cost me about 800...900 Euros. But I had to buy some new tools as well, and I used expensive audio transformers (because it's a full range design). So I guess without the transformers and tools it will have cost me about 300...350 Euros

* I had some trouble finding certain parts or materials, e.g. adhesive copper foil. I found that sourcing all the necessary materials was the most frustrating about this project.

* Build time: several months' weekends work. Often you can only do a little work and then the paint or glue has to dry so you have to wait a whole day, so sometimes progress is very slow...

When my speakers are finished (still plenty of work to do ...), I'll post some text & photos on my homepage.

Happy building,
kenneth

Hi,

The amount of time and money looks normal when you are trying to make everything in a more or less correct way.
Long time ago I have started with perforated metal.After half a year of experiments switched to wire stators. And never thought about perforated sheets again. Beaming, arching and sometimes leakage were the main problems. Of course it could be done, but it's no way an easy job. So let's try to make a comparison of main differences in construction :

Wire stators:
a) Building wire support frames(time consuming)
b) Stretching and gluing wires(somewhat time consuming, depending on tools and techniques used)
c) Radiation pattern control by using electrical segmentation(relatively straight forward)

Perforated steel:
a) Insulating perforated metal to prevent arching. This is in my opinion one of trickiest parts; very few powder coaters will be able to do the job well enough and with correct materials
b) metal sheets should be either curved or have supports to increase structural rigidity
c) radiation pattern could be controlled by either curving or using mechanical segmentation

Of course perforated sheet panel could be made without steps a,b & c but IMO in such a case it's more a test of concept than a serious speaker that is expected to work for years and is not a big headphone(what is the purpose of a speaker which needs your head to be anchored ..? :) ) or a cardiac arrest machine for those who are curious touching things with their hands ..? :flame:

So IMO you should not expect something much easier with perforated steel(perhaps coutrary..!).

Perforated metal has another significant con: typically much higher capacitance compared to segmented wire esl(also spacers can eat a lot of it).

Also I can not see a reason why wire stators should be less sensitive compared to perforated metal, given that area, spacing and other parameters are the same. On the countrary - round shaped wires are less prone to arching and could be driven with higher voltages which means higher maximum SPL.
 
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