ESL in a transmission line?

[Edmund]

Originally Posted by CharlieM

Hi Edmund,

ESL's with 6-micron or lighter diaphragms and good transformers can play to 20kHz+. I don't have a frequency response plot for my speaker that I can post for you, but I do use a DEQ-2496 EQ, with a microphone, and it shows response to 20kHz (the unit's RTA scale only reads to 20kHz and my digital crossover cuts off all output above 20kHz anyway).

As far as I know, polyester film (Mylar or Hostaphan) is still the preferred material for diaphragms. I'm not aware of any pre-coated film available for DIY use. The Licron Crystal coating isn't cheap but it's super easy-- 1 coat sprayed "just wet" is pretty much foolproof.

good luck with your project!

[Edmund]

Suppliers for ESL parts in Germany or The Netherlands?

I try to order the most basic things like a membrane and coating material
and end up with Australian suppliers of in China :-)
Not to mention I found :
“Mylar(R) is the registered trademark owned by the E.I. Dupont Corporation for Bi-Axially Oriented Polyester Film. There are dozens of different types and grades of Mylar(R), however the term is generically used to describe a range of different films.”
Can someone help me with what type of Mylar I exactly need for an ESL?
Since I found that some specialist in Australia has 3.5 micron which gives the best performance, I am looking for that thickness and give or take 600mm wide.

Edmund

[CharlieM]

Originally Posted by Edmund

Thank you, can you or anybody else confirm this:
TECHSPRAY | Products
Is the stuff I need?

Edmund

Yes, TechSpray Licron Crystal #1756 is what you want. I use the #1756-8S, which comes in an 8-oz aerosol spray can. I haven't tried the 1756 non-aerosol liquid.
One coat of the spray leaves a 2-micron thick film that's almost clear. Since it dries that thin and light, I don't see any need to try and dilute it or spread it thinner to save mass, as some are want to do. This is my preference.

[geraldfryjr]

Mylar type C is used for capacitors and electronic
Great choice but hard to find in wide widths.

Mylar type D is typically used for books and print coverings and is more commonly available.
It is a very transparent type of mylar

There many different types and some that have a heat sensitive glue backings such as model airplane coverings like Monokote and on some wrapped food products like you find on the top of TV dinners.

I am not sure but the R type that you have mentioned may be a reflective type, commonly used for reflective window coverings and such as well as antistatic bags and mylar balloons.
Don't quote me on this though as I have not found this label listing on the Dupont site yet.

Film Type Selector


Typically you want a mylar that is tensilized or has already been pre-stretched.

tensilized mylar - Google Search

As mylar will keep stretching up to a point then it will stop stretching.

This could cause the panel to lose its tension in time if it is not a tensilized type and would have to be re-tensioned.
This can easily be dealt with if you are using a mechanical stretcher by doing a test on a sample and making note on how far your sample can be stretched before breakage.

Typically that would be about 2%.

But a un-tensilized type may be able to stretch by as much as 4% or more before it stops stretching depending on its gauge of thickness.

jer

[MJ Dijkstra]

Originally Posted by Edmund

Suppliers for ESL parts in Germany or The Netherlands?

I try to order the most basic things like a membrane and coating material
and end up with Australian suppliers of in China :-)
Not to mention I found :
“Mylar(R) is the registered trademark owned by the E.I. Dupont Corporation for Bi-Axially Oriented Polyester Film. There are dozens of different types and grades of Mylar(R), however the term is generically used to describe a range of different films.”
Can someone help me with what type of Mylar I exactly need for an ESL?
Since I found that some specialist in Australia has 3.5 micron which gives the best performance, I am looking for that thickness and give or take 600mm wide.

Edmund

Hi Edmund,

No need to look in china or australia.
Check out the ESL-club in your own country.
You will find me there

Greetings from Holland

[esltransformer]

Originally Posted by MJ Dijkstra

Hi Edmund,

No need to look in china or australia.
Check out the ESL-club in your own country.
You will find me there

Greetings from Holland

And there are more supliers in the Netherlands (wich you can not find at the "esl-club"). I know a man in Haren(Groningen) who sells also mylar and I could deliver high quality costum made esl tansformers a well.

Greetings from the Netherlands again :-)

[WrineX]

So many dutch esl builders on this forum must be because where ought to be people that don't like to spend money, so better build ur own

[esltransformer]

Originally Posted by WrineX

So many dutch esl builders on this forum must be because where ought to be people that don't like to spend money, so better build ur own

I guess you are wrong, at least that was not why i build my own esl.

I build my own because i think i could do "better". And really good esl transformers are not normally available so i decided to build my own transformer too.