I bought the Massdrop X Noble K10 along with Campfire Andromeda and Solaris(I'm new to IEM). I've heard people saying that K10 have a very "safe" tuning compare to other IEMs, and that still holds true in my pairs of Noble K10. My first impression on these aren't great, to be honest, very underwhelming. I pair my IEMs with iPhone via lightning cables and Wooaudio WA8. First minute I tried these on I felt like these 10BA IEMs are not resolving at all. I decided to give them a 10 hour burn-in period. I switched to the lightning cable for the burn-in, and after the burn-in, I'm quite surprised how good they sound! When connected to the WA8, it has very good BA bass, maybe not as clean compare to Andromeda, but the rumble is present. Mid is quite good, it is a bit on the lean side but totally acceptable. Treble wise, I do occasionally get that sibilant sound, but overall it is not bad, it has some sparkle in it.
The Massdrop X Noble K10s are well worth the price, and I feel that it fits my needs perfectly. Sound wise if I'm connecting it to my DAC/AMPs they don't sound as good as my Andromeda(and not even close to Solaris). However when only using a lightning cable, k10 sure does have the edge on how it scales. It is a great choice for those who don't want to carry extra pieces of gear such as DAP/DAC/AMP around and looking for beautiful sound straight out from that lightning cable. (Massdrop customer service is great as well, there was a tip missing from the package and they send me a partial refund so I can purchase another set of tips, good on them.)