Apologies if I should be asking this in the Swap Meet section instead of here but figured I may get more responses here; please move the thread if need be.
Anyway I am looking into from where I can buy some Mylar and other ESL supplies. Plain and metalized in the popular or wider widths and thinknesses suitable for building a DIY ESL. So far I've found the following through ggogle and searches on here. If you can think of any others please reply. If you have your own surplus to sell feel free to reply or PM. Also interested to know about any postive/negative buying experiences if the rules here allow ( can't remember ever reading the rules! 🙂
Anyway I am looking into from where I can buy some Mylar and other ESL supplies. Plain and metalized in the popular or wider widths and thinknesses suitable for building a DIY ESL. So far I've found the following through ggogle and searches on here. If you can think of any others please reply. If you have your own surplus to sell feel free to reply or PM. Also interested to know about any postive/negative buying experiences if the rules here allow ( can't remember ever reading the rules! 🙂
In the US I'd go to McMaster-Carr: www.mcmaster.com
I'm sure they'll ship to you but it probably won't be cheap.
Tom
I'm sure they'll ship to you but it probably won't be cheap.
Tom
ER Audio is often recommended.
https://www.eraudio.com.au/
Most metallized films made for other applications are unsuitable for use in electrostatics (resistance far too low, and potential longevity issues).
https://www.eraudio.com.au/
Most metallized films made for other applications are unsuitable for use in electrostatics (resistance far too low, and potential longevity issues).
Hey... Crazy thought. Isn't overhead film made of mylar? That stuff used to be in every classroom on long rolls.
Tom
Tom
Films appropriate for most electrostatics are at or below 1/2 mil thickness (0.0005 inch - the mil here is for milli-inch, which confuses people). If you prefer metric, that's about 12 microns. These days many people view 12 micron as thick for full-range use, but it was common years ago.
Thicknesses like this are harder to find in general, and much thinner than what's used for overhead projection film. Some plastic-specific suppliers have them, but it's not that common and you often have to take whatever brand of polyester film they carry (Hostaphan used to be the other common one). Unless of course you want to buy a full roll, but they're typically a few miles long. I used to know a guy that worked at a film processing facility, and the scale of everything they did was wild. Their scrap room on any given day had more film in it than the entire DIY speaker hobby has used or is likely to ever use in the future.
That's why electrostatic speaker specific suppliers are out there. They already sourced the right stuff and save a bunch of trouble trying to find it.
Thicknesses like this are harder to find in general, and much thinner than what's used for overhead projection film. Some plastic-specific suppliers have them, but it's not that common and you often have to take whatever brand of polyester film they carry (Hostaphan used to be the other common one). Unless of course you want to buy a full roll, but they're typically a few miles long. I used to know a guy that worked at a film processing facility, and the scale of everything they did was wild. Their scrap room on any given day had more film in it than the entire DIY speaker hobby has used or is likely to ever use in the future.
That's why electrostatic speaker specific suppliers are out there. They already sourced the right stuff and save a bunch of trouble trying to find it.
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12 µm is normal for bass/mid diaphragm and dust cover. Treble is usually 3 to 6 µm. Spacing, tension and HT bias should be in harmony in order not to stick the diaphragm to either stator by electrostatic force.
I read a paper on the relation between thickness and upper cutoff frequency, but I can't find it. A JAES article perhaps?
I read a paper on the relation between thickness and upper cutoff frequency, but I can't find it. A JAES article perhaps?