Great post and keep up updating! Btw, I just bought that silver-transparent-white 2-pin with black rings jack cable You measured lowest impedance. Hopefully will get same good one. Will measure mine when I get it and post results. NiceHCK one with white rings really isn`t good when it comes to numbers (too high & uneven impedance), maybe will try to make it into custom (wooden plugs&bits) and resolder, maybe helps.