There also is a red module available through FIR’s shop, that will go to 10db isolation and minus 4db bass response. A single pair of these would set you back another 49 USD. All IEMs have been tuned with the silver module.
One thing I want to note about the ATOM XS modules is, that the gold one lost its color rather quickly after I unscrewed it. Making it hard to distinguish and separate from the silver module.
On the bottom of the unit you will notice the opening for the Kinetic bass driver, which faces in direction of your concha. Now, I was very curious to see how different the experience between custom and universal will be. I have to say, on my custom Xe6 the perception of the bone-conduction is bigger. I don’t get the same sensation from the Kr5 that I get from my Xe6, even at home. That definitely is because the surface area does not make the same contact with my skin. I want to point out, that my girlfriend told me that she does feel the Kinetic bass noticeably and probably even more than me. So that is definitely down to the nature of your ears. It only makes sense, that the custom will give you (me) more pleasure in that regard.
On a comfort level I am happy to say, that I could wear the Kr5 on hours on end, without ever getting into ear or listening fatigue.
Sound
For the sound section I have used an array of DAPs (Lotoo PAW Gold Touch, PAW6000, Astell&Kern AK120ii and Sony WM1A) as well as my Chord Hugo2 and Hugo TT2 over the course of approximately two months. The Krypton 5 did not pick up any noticeable hissing from my DAPs, but there was waterfall noise on both Chord units.
The following has been written with the silver module installed, as it’s their default tuning. I will briefly go over the changes accompanied by swapping the modules.
Summed up in a few words, I’d describe FIR’s Kr5 as somewhat V to W-shaped sounding set, with bass that delivers punch and authority, thinner yet speedy and precise mids and a forward treble. The Krypton will have you in awe when it comes to resolution and stage dimensions. It’s a master of layering and imaging in my books.
Right out the bat, the Krypton 5 has an energetic sound with fast, dynamic and well defined bass. It reaches remarkably deep into the sub-bass levels with a bunch of authority and grip. Lows have very good body and weight, where they sound full and dense, but not so much, that they become slower sounding of any kind. What I really like about the bass, is that it can also take a step back. It’s not always here. But when you call that DD/BA combo it sure makes an impact.
Bass is incredibly controlled and comes with heaps of details. The texture and layering of lows is just astonishing to me. You get to hear all the little details that surround low-end notes. It’s a part that truly sets a new benchmark for me.
The Kinetic bass is one of FIR’s standout features, it’s a bass you can feel. I mentioned it earlier though, it doesn’t work as well on the Kr5 as it does on my custom Xe6. Now, where I’m sitting at my desk typing down these lines I can focus on the sensation. While I am noticing it more clearly, it still doesn’t wow me like the Xe6 did. Again, it’s all down to ear-anatomy. Maybe mine aren’t best suited for the universals.
The midrange of the Krypton is a little thinner, but still on a degree where instruments don’t sound hollow or filled with air but nothing to support it. Mids are very detailed and to some extent transparent, but not anaemic. There is enough weight and body in them to give them a more natural sound, yet I am personally missing some richness to give them an all natural sound. Especially vocals could use a dose of extra weight in my opinion.
On a technical performance level I think the Krypton is one of the very best performers currently available. It’s hyper detailed with incredible resolution. The Kr5 will show you every little beep and paint a picture as sharp as it gets.
The stage is another part that the Krypton really does exceptionally well. It has one of the biggest stages I have heard in an IEM. It reaches out of your head in all directions, creating a large venue type of sound, reaching almost holographic levels. The Krypton also puts everything on an incredibly dark background, highlighting the musicians and instruments with great care. Each instrument appears to stand on its own very solid ground, and bundled with the high resolution that produces pin point imaging and separation.
On to the treble. This is a part where your own sensitivity comes into play. If you’re very sensitive about that region, you will probably find the Kr5 too forward. I personally do not have an issue with the tuning here, but I let my girlfriend listen to the Kr5 a couple of weeks ago, and the treble was too much for her taste.
Treble is detailed, forward and super fast. To my ears it is not sharp or too edgy. There are corners and edges to it, but there’s enough softness and smoothness to keep those edges from becoming too hard. Highs extend very wide into the upper treble, with the Kr5 pushing the highest registers on a noticeable level, delivering a lot of air into the sound.
If you’re listening to music with a lot of crashing cymbals, you will most likely notice the brighter and more forward tuning of this set. Personally, I even found that too much at times, switching to other music with less action up there.
Let’s quickly go over the Atom XS modules.
With the gold module installed, the bass becomes a bit more forward and authoritative. Giving a more solid and punchy low end, as sub-bass gets a small bump in volume. The mids did take a small step back in the signature, but kept their body and weight numbers at the same level. Treble did not change much, if at all.
The black module gave bass a little less prominence, dialling them just a tiny bit back. Mids on the other hand did step forward, while their body and weight again did not see a change. Treble remained at the same level.
Between the three my favorites were the silver and gold modules. But I kept the silver module installed pretty much all the time.
Find out how the Kr5 holds up to its competitors on page three!
Kevin F
Curious about what ‘waterfall’ means in terms of the Hugo2.