ESL Stiction?

[Atom66]

Interesting discussion on "Stiction" and DIY ESLs .
http://groups.google.com/group/aus.h...cd3204f6a5046c

Andrew

[I_Forgot]

There is no mystery here.

Patrick Turner's problem with "stiction" is that he has insufficient diaphragm tension for the insulator thickness/bias voltage used.

I'd guess that he heat-shrunk the diaphragms to tension them.

I_F

[stokessd]

Heat shrinking is iffy at best. And the shrinking tension can really vary batch to batch of film.

Sheldon

[Lucius]

Originally posted by stokessd
Heat shrinking is iffy at best. And the shrinking tension can really vary batch to batch of film.

Sheldon

I guess your DIY ESL1 posted on your web site is now passe'. I have gathered the materials to make something similar, only mono & same size & shape as Quad 57.

For the membrane I have 4mil(10microns) PVDC. Anyone with any experience stretching/heat shrinking PVDC?

Lucius

[stokessd]

I do a tensioning method using a spring scale and packing tape. It was pioneers by Rob Macinlay at ER audio. It's brilliant and doesn't require a stretching jig etc.

The ESL's that I built are still outstanding speakers. I just don't do much sitting in my listening room serious listening anymore. I'm thinking of selling my hardcore gear because I just don't use it anymore.

Sheldon

[Few]

Sheldon,
I can guess what the basic idea is with the spring scale and tape, but if there are any tricks to making the technique work well, would you mind sharing them (assuming they're not supposed to be proprietary ER Audio info)? I'm guessing you attach packing tape strips to the mylar and have some way of attaching the tape to the scale. Do you use an extra long piece of tape so that with one end attached to the diaphragm, and the other end attached to the scale, there's still some exposed adhesive in between that can tack the tape to the support surface and hold the diaphragm under tension? Or is there a better way?
Few

[SY]

PVDC: Not a good ESL diaphragm material for several reasons, lack of shrink being a biggie; unless heavily plasticized, they tend to be pretty crinkly, too. The plasticized ones lose tension with surprising rapidity.

[Lucius]

Originally posted by SY
PVDC: Not a good ESL diaphragm material for several reasons, lack of shrink being a biggie; unless heavily plasticized, they tend to be pretty crinkly, too. The plasticized ones lose tension with surprising rapidity.

Thanks for your input. I've read some of your posts where you have said PVDC would be your favorite or in this case:" FWIW, I use a Saran film (real Saran, PVDC) which works very well, but film that thin is not trivial to obtain."-Sy
What happened since your posts that you now do not recommend PVDC?
What I have is made by Dow & is .0004" thick.

Best Regards

Lucius

[SY]

I ended up using Clysar, since the plasticized Saran just wouldn't hold tension, but it did have a great sound while the tension lasted. Which Dow Saran did you get? (That's exactly what I used)

[Lucius]

Originally posted by SY
I ended up using Clysar, since the plasticized Saran just wouldn't hold tension, but it did have a great sound while the tension lasted. Which Dow Saran did you get? (That's exactly what I used)

I got it from the Link below which came about from some posts by you & Captain Jack a couple years ago. The thinest gauge they list is 50 Gauge but if you prod them, they have a 40 Gauge. Perhaps you can tell me what I got, plasticized or not? Did you heat shrink or stretch? I will build the panel to make it easy to re tension with heat.
Is it best using a hair dryer or a heat gun?
I got a roll of this around 3' wide & too too long. They told me they would put up this order if I would come back to them. I had to be honest & said this will be good for life but if it came up I would post their site on diyaudio, which they approved of.

http://www.filcon.com/fil/home.nsf/P...Saran_Wrap.htm

Lucius