You know I do have an impedance adapter that I bought from a Lazada store in December of last year. It was intended for the red ZS6 i already had at the time.
Long story short, i didn't like it.
When I connected it to the ZS6 and then to my iPhone 6+ (EQ Off) the result was an attenuation in volume approximately equivalent to 3 clicks on the side volume buttons of the iPhone (~about -10.5 dB). It also made everything so much warmer and extremely smooth all the way up. No textures whatsoever. Yes the initial harshness and over-brilliance of the ZS6 did disappear but the smoothness was quite disconcerting. It's like listening to a vinyl tube-amp 2-channel stereo system with the treble turned down. Or, as the thought jumped into my head at the time, like diving into a pool filled with depilatory lotion; the entire skin surface became smooth with all the hair gone, including eyelashes and nose hairs.
So, I read instead the posts of hakuzen (as a lurker here) about his research as regards taming the ZS5 v1 and ZS6, first using EQ, then ball foam tips and that last was the solution for me.
Anyway I dug the adapter up and here it is... a "Shenzhen Audio ZY-031 HiFi Nüwa Copper Top 10cm Impedance Cable" with a Canare F12 plug. All the other details are in the photos. Price then was the equivalent amount of $21.62 US. Now it's $57.98 on Shenzhenaudio.com. Seriously heavy, evidently built like it's part of an armored tank and looks like it could survive a nuclear explosion, much more any random peak bursts (sorry, couldn't resist).
Here are screenshots of its Shenzhenaudio.com page (as soon as I read the product description, the same in the Lazada store as it is below, I ordered it right away—guess I was a bit excited):
I just kept it in a drawer and never thought about taking it out till now. Will try it out with the Cayin N3-Topping NX4 and ZSN sometime.