Summary for conductive mylar Discussion
Conductive mylar for electrostatic loudspeakers can be made a few different ways, and the thread shows two practical approaches. Frederick asked how to coat Mylar without adding too much weight, suggesting conductive paint but worrying it might be too heavy. One answer proposed chemically activating the Mylar in a sodium dichromate and sulfuric acid bath so it can be electrolessly metallized and then thickened as needed. A later answer from Vin Heiry said vacuum-metallized Mylar is widely available from art and craft stores and even dollar stores; he noted it is usually about 1/2 mil thick and works well as a speaker membrane, though it may be more conductive than the ultra-low-conductive films used by major manufacturers. His experience replacing original Mylar in electrostatic speakers was positive.
Q. Dear All,
I’m thinking of building a pair of electrostatic loudspeaker and is having problem the conductive mylar. Could anybody advice me how to coat the mylar sheet so that it can be conductive?
I’m thinking of conductive paint, but worries that it might be too heavy on the mylar.
Thank you very much
Frederick
hobbyist – Singapore
2003
A. Activate it in a mixture of 41 g sodium dichromate dissolved in 210 mls of water with 770 mls of concentrated sulfuric acid. Dip it in for between 5 and 30 seconds at 75-80 °C. The Mylar can then be activated for electroless metallisation and subsequent thickening as required.
Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK
2003
A. Vacuum metalized mylar is available at most art and craft shops. even some dollar stores. It is not translucent, but is typically 1/2 mil thick and works well as a membrane for electrostatic speakers. The only drawback is that it has more conductivity than the more desired ultra-low conductive films used by major manufacturers. I have used it to replace the original mylar in many electrostatic speakers, and find it works quite well.
vin heiry
Hobbyist – E. Brunswick New Jersey USA
March 10, 2022