I definitely think the k10 is better than the original jh13 but for me, the 13FPs give both those and the Roxannes a run but they're all different enough for any given subjective perspective of the 3.
That is interesting. I auditioned the JH13(FP) with the Roxanne and found that the Roxanne was a bit too bassy for me with a slightly darker sound than the 13. I have not heard the K10, but that was my initial target for a CIEM from the start.. Sadly I couldn't find a place to demo them so I went with the JH13 with a lot of what-if's.
After over 2 weeks of living with my JH13FP, and getting used to the fit which changes on a daily basis for me (some days perfect, some days a tad lose), I have to say that I don't think any other CIEMs around the same price could be a definitely better than the JH13FP, and anything above the price would only be an incremental improvement which would not be able to draw me away from my 13.
I may or may not be changing my tune upon hearing the Layla or K10 (in the future), but I highly doubt that I will. I think I have reached my end game for CIEMs.
Some thoughts on the 13:
I find the 13 to be...contradictory. I can't detect that bass hump in certain tracks while on other tracks it presents the frequency between the mid and lower bass with a very commanding presence. I do find the midbass to be slightly soft on rare occasions, but they are viscerally smooth most of the time which is another contradiction.
The mids are the weirdest part for me. Sometimes they feel quite forward and lush, other times they recede slightly and sound a bit thin. And these are with tracks that I've listened to thousands of times, so I'm REALLY familiar with them. I have no idea what's going on.
On brighter tracks, I do feel that the 13 pushes the bass back a bit more than my other headphones do, but omg that occasional sparkle sounds awesome to my ears. However, the 13 does present the highs of certain tracks harshly, especially cymbals and other treble sounds with long decay.
Do you guys have the same experience with the 13? Sometimes it sounds like a smooooth Denon 5/7k, other times it sounds like an ACS or even a HD700/800. I feel like I'm listening to 3-5 different headphones sometimes.