Q: DuPont Mylar Film for ESLs...

[Rarkov]

Hi,
I am trying to source some 0.5mil (12.7micron) DuPont Mylar Film in the UK. After mistakingly quoting 2microns, I was knocked off my chair with £200 for 3mx49cm! When I finally got the correct data, it was quoted as £60 for 3mx30cm. Does this sound right? I need a larger width than 30cm though...Anyone know where to get it in the UK? It needs to be more like 50cm.

Please help!

Thanks,
Gaz

[peterr]

these prices are absurd. Don't do it.
Look here for inspiration mylar

[kelticwizard]

I don't have the link handy, but someone on this forum has mentioned that someone in the US sells Mylar in a form that allows the builder to take a hair dryer and shrink it to a perfect fit once it is installed. He gives a supplier. I don't believe it was terribly expensive. You might try a search here on the forum.

The only thing I could add, apart from peterr's link, is here in the US they sell 2 foot by 3 foot sheets of Mylar for gift wrapping paper. They come in packages for a dollar. So the stuff should be cheap, assuming you can locate a supplier.

Good luck.

[ashok]

these prices are absurd

Absurd is a very mild term for that price (60/- pounds).
I bought some from the US by mail order. I paid some US$20 I think some 3 years ago. Look for ESL on google and it will come up. I also bought two transformers from him. I am getting old, I forgot his name for the moment. It came folded ( not very sharp bends).
Its about 48 inches by 36 inches I think, maybe a bit bigger.

About the same time someone posted a message on the ESL web site ( can't remember where!) that he bought a whole roll in Tokyo for US$80 or 100/-. That was about 36 inches wide by over 100 feet - or was it meters! I remember thinking that my price was about 10 or 20 times more. Better you guys get together and see if you can buy left over rolls from electrolytic capacitor manufacturers.
Cheers.

[Steve M]

Hi Guys,

Try Rob Mackinlay - E.R Audio in Western Australia @ www.eraudio.com.au for all things ESL!

He sells 12um mylar for $1.10US per meter X 800mm wide. Also, supplies the dielectric coatings; transformers; rectifier blocks etc. and full range ESL speaker Kits at very reasonable prices.

Just a little tip, the 3.8um micron Mackinlay supplies is much better than any other thickness, being significantly more detailed and transparent sounding. I currently use and listen to E.R Audio's ESL-3 full range electrostatic loudspeaker...it's a wonderful speaker! Having much better transient response and micro-dynamic detail retrieval than any Quad ESL; Accoustat or Martin Logan I've owned or heard.

I will do a full review on the ESL-3 on this site in due course.

Regards,

Steve M.

[schpeltor]

I got a 30" X 100ft roll (may be longer) .5mil from Professional Plastics for $40? I may have mixed some things up, but that info should be correct.

[MRehorst]

In the US McMaster-Carr has 5 or 6 micron polyester film, though the size may be limited. They also have perforated steel and aluminum sheets to use for the stators.

When you specify "Mylar" you get DuPont's product- Mylar is their brand name for polyester film. You can use any manufacturer's polyester film with excellent results. The film I use is called "Lumilar" and is made by a Japanese chemical company called Toray.

I would not make speakers using only a heat gun or hair dryer to tension the film. You can not get much tension that way so your speakers will exhibit very low sensitivity because you'll have to keep the bias voltage down to keep them from flapping. You will need to make a mechanical stretcher. Such a device will allow you to put a huge amount of tension on the film and run your bias supply at maximum possible voltage, thus giving you a speaker that can be driven to very loud levels by a "normal" power amplifier.

I have posted photos of a pneumatic stretcher I use on these forums - do a search. The stretcher is extremely easy to make and use and you won't regret trying it out.

MR

[Rarkov]

Hi,
Sorry for the delay in replying...
Thanks for all of your helpful posts. I have sent a cheque off to One Thing Audio (from a link in peterr's link). The owner is charging £30 for 10m...That far more like it. The is very little possibility for finding "scrap" / surplus parts for the ESLs around where I live, so it's going to be a long, slow and expensive exprience!

BTW, I've had a couple of ideas...

1) I have a dog and I am a bit jumpy about the idea of his wagging tail hitting things it shouldn't! (He's a v. long haired English Collie!!!) Am I able to mount ESLs on the wall - in the same fashion as a picture? I plan to have them either side of my fire place - but there is no room on the floor!

2) I'm also jumpy about touching things I shouldn't! What is a sensible way to cover the front / back(?) stators? I thick acoustic foam as used on some normal loudspeakers OK? I assume this would keep out dust aswell?

3) Can I run my normal speaker cable to the ESLs if the electronics are in the ESL or do I need to beef them up a bit.

Finally...Mr Sanders seems to reason that no amount of power is enough for these things! I'm intending on making these things about 40cmx120cm (which should be about midrange). Are 140W monoblock amps (actually slightly higher due to rasied rail voltages - more like 160W) OK for this application?

Thanks very much for your help again!
Gaz

[MRehorst]

Originally posted by Rarkov

1) I have a dog and I am a bit jumpy about the idea of his wagging tail hitting things it shouldn't! (He's a v. long haired English Collie!!!) Am I able to mount ESLs on the wall - in the same fashion as a picture? I plan to have them either side of my fire place - but there is no room on the floor!

>> Right against the walls is a lousy way to use ESLs. It will work, but don't expect hi-fi. ESLs like a lot of room behind them. It is a relatively easy thing to protect the speaker from the dog and vice-versa. Build a frame around the ESL panel that is a cm or two larger than the ESL is thick. attach dust covers to that frame, made from the same material you used for the diaphragms. These will keep hair and **** away from the drivers. Then cover with a chicken wire mesh (wire screen with big holes), then put a pretty piece of thin cloth over it. Make sure the dust covers are tight and have a little room to move. Wrinkles will make rattling noises on bass notes.

2) I'm also jumpy about touching things I shouldn't! What is a sensible way to cover the front / back(?) stators? I thick acoustic foam as used on some normal loudspeakers OK? I assume this would keep out dust aswell?

>>> see above.

3) Can I run my normal speaker cable to the ESLs if the electronics are in the ESL or do I need to beef them up a bit.

>>> I don't know what your definition of "normal" is, but 12 ga zip cord is about as good as it gets (wait, I have to zip up my asbestos suit...).

Finally...Mr Sanders seems to reason that no amount of power is enough for these things! I'm intending on making these things about 40cmx120cm (which should be about midrange). Are 140W monoblock amps (actually slightly higher due to rasied rail voltages - more like 160W) OK for this application?

>>> 140W is plenty, assuming you are using reasonable ststor thickness and bias voltage. I also agree that you can never have too much power available. I run my ESL 63s on 200W/ch normally. Recently I have hooked up an LM3886 amp I built (about 30W/ch)and they play loud and sound great.

Thanks very much for your help again!
Gaz

[MRehorst]

Flat panel ESLs are extremely directional. You probably won't want to sit them on the floor because of the problems involved in aiming them at your ears. Think about stands that get the panels up to ear level when you are seated in your favorite chair. That way they'll be up where you need them for best sound, and out of the way of the dog's tail and wee wee.

MR