For those interested, here are the only impressions in English of my custom IEM on the way.
I'm getting the CX6 through Gui Ling (the oldest/most experienced custom IEM manufacturer in China).
We discussed it a lot and he's agreed to tweak it a little for me with his ideas and my ideas, so he thinks it will sound even better than the original CX6 with this new config, so I'm not really getting a CX6, but quite close, like CX6 ver 2.0, and I'm giving it a new name like that to avoid confusion.
Here's the CX6 impressions I have from a friend in Singapore that has tried the JH13, Miracle and CX6.
"Hi Kiteki! I'm back from hearing the CX6!
First of all, the customs didn't fit me at all, so it was troublesome; i was practically struggling to maintain seal throughout the whole listening session, by cupping my hands over my ears, and also shifting the IEMs around inside my ears. It was quite terrible trying to skip tracks, control the volume, and maintain my seal altogether!
But when I did get a decent seal, the sound was pretty amazing! If the RE0 had 10.5 treble and the miracles had 9.5, I think the CX6 has a perfect 10! It is just where I want it to be, with enough sparkle and brightness. The mids are a little weird. In some songs they seemed to have disappeared. In other they JUMPED right out at me, roaring. But when they were there, they were awesome, in fact I would think it is comparable to the Miracles' mids. Other times they seemed to have gone into hiding. The whole sound signature surpassed everything I had originally wanted! He told me the sound was totally flat. In comparison, he says that the JH13 are more fun-sounding.
The soundstage doesn't seem very wide; it was very intimate, and yet the positioning was really good, just like the JH13. What was amazing was the singers seemed to be singing right into my ears, in both directions. I couldn't really describe this, but later on he explained to me this is transparency. Normally we hear from earphones, and there's a left sound, and there's a right sound, both coming from where our ears are. He said the CX6 and his cable were tuned such that the sound merges accurately together in the centre, right in my head.
Did the CX6 wow me? I think so. I'm not sure if I was that much wowed by the Miracles and JH13.
Sound-wise, I was surprised the RE0 actually didn't sound that nice when I listened to it on my way back.But I'm also not sure if it was the cab's rumbling noise that resulted in my RE0 sounding not so nice. What I cannot tell though, is if the details are as defined as what I had heard on the Miracles and JH13. His place is too far from town."