FiiO FD5
Build
I actually welcome the 11 grams (per piece); they’re not heavy, like the iKKo OH10 (16 grams). I have a serious dislike for the lighter weight, all plastic shells, like the CCA CA16. Where if the shell isn’t a near CIEM fit for you, the lighter shells require constant re-adjustment.
Burn in
It's real. Doing a quick check for DOA, the FD5 is dark, due to a lack of upper frequency response; a few hours later, they've more than opened up
(more to follow on their being too bright for me).
Clarity
(You’ll see me repeat myself over and over, on how the FD5 hits the right balance for a section of notes)
The FD5 has the ability to project both macro and micro details, to a high level. I don't have a measuring rig (outside of my ears), but I would guess (from my experience with other IEMs, that feel like a needle is poking me) that the 2K - 4K bump is just on the cusp of my tolerance, as I did not find the FD5 sibilant. Yet that spike/bump, in the upper frequency response (in the 2K - 4K range) is the danger zone for my overly sensitive ears. Using the stock (wider) nozzle, I find the FD5 to be easily fatiguing. I remedied the "bump" by applying 2 plys of foam, to the inside of the (default) larger nozzle. But that's just me, others may only need 1 ply or none at all. It's always better to start with more than you need (in this case, upper frequency range) and find the right amount of cut, for your needs.
I found that it’s critical that the filters be “rammed” home evenly. Using a large toothpick created an uneven seating, against the inside of the nozzle’s screen. A plastic coffee stirrer turned out to be the right width, for an even seating.
HA FD01 vs. FD5
They definitely share DNA , but the FD5 is the equivalent to the rich uncle, vs. the FD01 representing the well to do, weekend Dad. The FD5 plays wider and with an added weight, while not sacrificing detail, for the weightier floor. I had resigned myself to certain genres (like my re-discovery of 70’s Rock) just play kinda flat. As recordings from 40 yrs. ago just weren’t meant to replicate the live concert experience. Now listening to Led Zeppelin’s “Stairway to Heaven” on the FD5, I’m there, in the 1st tier of the crowd.
For the bassheads
9.5/10
Using Ying Yang Twins (Get Low), I can feel it and it’s clean. The FD5 is neither fast (to recover a deep bass note) or drops off a sheer cliff, there’s a good amount of resonance.
Mids
Like everything else, they're clean, but not neutral. The FD5 doesn't exhibit any appreciable mid bass bleed, which allows male vocals (like Sinatra, Nat King Cole) to stand on their own, while remaining true to the artist.
Audio chain:
Samsung Note 20 (the one that everyone pisses on), set to LDAC, 990 kb --> Tidal HiFi/Master --> Qudelix-5K
[edit, forgot to add PEQ settings]
Footnote:
At some point I'll try the stock cable, but for now, I'm on a high purity copper cable