Great review Amir! I bet some of us always wondered how those ancient headphones would sound and measure like.
You measured a product from the Koss lineup, is there a chance you would do an evaluation of Koss ESP950/95X (massdrop)?
This is review and detailed measurements of Drop's X KOSS ESP/95X electrostatic headphone. It is on kind loan from a member and when it was available, cost US $500. Not sure what is different with it from the original KOSS model which I think cost $1000. Typical of most electrostatic...