i ordered it and it's in transit now. will measure it as soon as it arrives. about trn 8c cable, i don't know what they've done, now. 2 cores should be used for each signal. in the case of single TRS jack, it seems that only 1 core is used for left signal, and 3 cores used for left ground. so you'd have to re-solder not only into the jack, but also into the 2pins plug. but in the case of TRRS, it's left+ signal vs right- signal! they are in different groups (4 cores to left driver, 4 cores to right driver). so i'm puzzled. i don't know what's happening then.