FIR Audio Frontier Series: Krypton 5 Universal IEM

These headphones were created by geniuses. Perfect sound, does not hurt the ear in the upper range, perfect mids, deep bass with a subwoofer effect.
P.S.Andrew the best person ever .

Very happy with my latest acquisition. The mid-bass performance is the best in my collection, visceral sounding!

FIR Audio Frontier Series: Krypton 5 Universal IEM

FiR Audio Krypton 5 is an excellent IEM. Build quality is exceptional, ear pieces are comparatively small and lightweight for a multi driver hybrid, they are comfortable in ear, and fit should not be an issue for most people.
The ATOM XS modules are very small, and finicky to handle and swap out, but the noticeable impact they have on the sound signature validates their value.
Kinetic Bass proves to be more than just a concept. The bass on KR5 is full, and rich with punchy impact when called upon. Sub bass is well defined and has the ability to extend extremely low.
Mids present forward, and are clear and detailed.
Vocals are also forward, natural and accurate. They blend seamlessly with mids instrumentation.
Highs are crisp and clear with good air, but never sibilant or harsh. Micro detail retrieval is very good.
Soundstage is above average. Width is between the ears, or just a bit outside the head. Vertical depth (height) is exceptional, good air takes it high, and the sub bass has the ability to pull it really low. The forward mids and vocals provide very good front to rear depth. Layering and separation are very good, and imaging allows for precise and accurate individual instruments placement.
FR5 performs on par with other Flagship IEMs from Empire Ears, Vision Ears, and 64Audio in similar price range.

+ Top resolution
+ well controlled agile and quite present bass.
+ one of biggest stages with open back imaging.

- treble sensitive might struggle with signature.
- isolation is poor.
- slight leak of sound on high volumes(but im using in office wothout issues on normal volume)