NF Audio RA10


Headphoneus Supremus
NF Audio - Micro driver? No problem
Pros: + Small and comfortable shells
+ Tonally correct
+ Competent level of clarity and detail
+ Good imaging accuracy
Cons: - Weak bass response
- Small soundstage
- They don’t look as good as the marketing materials
Are modern IEMs becoming too large?

One of the most common feedback I receive when giving purchase advice is, “thanks, but these IEMs are too big.” As IEMs pack more and more drivers to (try to) achieve a better sound quality, comfort takes more and more of a backseat. In the current landscape, your choices of small IEMs are limited to a few options, from Shure, Westone, and the famous Sennheiser IExxx series. This gap in the market is why I find NF Audio RA10 interesting.

Let’s talk about these tiny IEMs.

tl;dr: an alternative to the famous Sennheiser IExxx IEMs if you crave their comfort but not their bass nor their price



  • This review is based on a sample provided by Penon. Unaffiliated link to the product here
  • You should treat this review as the subjective impressions of an audio geek rather than an “objective truth” about the IEM. Your experience with any IEM would change depending on your DAC/AMP, music library, ear tips, and listening volume.
  • I rate IEMs by A/B testing them against a few benchmark IEMs, regardless of price point. This approach ensures the consistency of the ratings in my ranking list. It means that if two IEMs score the same, they perform more or less similar.
  • I believe that great IEMs are the ones that can achieve multiple difficult things simultaneously: (1) high resolution (meaning lines of music are crisp, clear, easy to follow and full of texture), (2) 3D soundstage with a strong sense of depth, (3) bold and natural bass with a physical rumble, (4) natural timbre, (5) relaxing and comfortable tonality.
  • Ranking list and measurement database can be found on my IEM review blog.


  • Driver: 6mm micro dynamic driver
  • Connector Type: 2-pin
  • Impedance: 15ohm
  • Sensitivity: 102dB/mW

Non-sound Aspects​


NF Audio is an unfamiliar manufacturer to me. My experience with this brand is limited to RA10 and a few impressions shared by others in the Discovery thread on Head-Fi. As far as I know, NF Audio generally has a (delightfully?) quirky presentation with most of their products.

This characteristic carries over to RA10, a more budget offering. I like the simple but striking way they design the box, relying primarily on typography and shapes. The way NF Audio packs the content inside the box is also efficient and slightly unusual. I, unfortunately, ripped the internal packaging before the photo shoot session, so I can quite show you how it looks.

What you get in the box is more conventional:
  • RA10 earpieces
  • 2-pin braided cable
  • A cloth bag with velour lining
  • A set of silicone ear tips called MS42

Let’s talk about RA10 earpieces. They are tiny. Smaller than my Shure SE215 and matches my “IE900.” In fact, you can fit a few RA10 into the shells of chunky boys like Moondrop Blessing 2. The prime benefit of such a design is comfort. RA10 sits flush against the concha of my ears, allowing me to lie down on my side with zero discomforts. My only complaint about the earpieces is that they could be better built. The marketing material led me to believe that RA10 is constructed from dense, glossy plastic like Campfire Audio Satsuma and Honeydew. However, the plastic quality and moulding are not as good in real life. Disappointing, though understandable, given the price.

Before we move on, let’s quickly touch upon RA10’s accessories. The included cable is fully serviceable. It is thin and soft and therefore pairs well with tiny earpieces. The cloth bag is large enough to store RA10 snuggly if you roll the cable up with 4 fingers.

Regarding the ear tips, when you unbox RA10, you will notice that it is already equipped with a pair of silicone tips. I binned them immediately due to how poor they fit. The MS42 tips fit better and thus sound way better.

How it sounds​

Sources for listening tests:
  • Fiio K7 (for all A/B tests)
  • Topping G5
  • Shanling M6 Ultra
  • Hidizs S9 Pro
Local FLAC files ripped from CDs or bought from Qobuz were used for most casual listening and A/B tests. My playlist for A/B tests can be found on Apple Music here.

I use the stock cable and medium MS42 for all listening tests.


Tonality and Timbre: 4/5 - Good​

Frequency response of NF Audio RA10. Measurements were done with an IEC-711-compliant coupler and might only be compared with other measurements from this same coupler. Visit my graph database for more comparisons.

Recently, I read an essay from Arthur Schopenhauer stating that our first impressions are the most objective as our intuition has not been tainted by subjectivity and biases. Of course, Schopenhauer was talking about people, not IEMs. But for the sake of our review, let’s assume this statement also applies to expensive audio toys. Here are my first impressions of RA10:

  • RA10 sounds right. None of the vocals and instruments in my test track raises any red flag. No honkiness, no nasally or strained tone, no muddiness.
  • There is a sense of “lightness” in the tonality of RA10, a diffused-field, Etymotic-like sound if that makes sense to you. The midrange feels open and transparent. It means I can hear vocals and instruments clearly without feeling that some elements are masked by others. On the other hand, no warmth is added to the mid-range of RA10, so some listeners might find RA10 cold.
  • RA10 sounds mild. Singers do not sound like they shout to my face. Note attacks of guitars, strings, flutes, and cymbals are not emphasised, so they do not sound like ice picks to my ears. Sibilance is not highlighted beyond what is already there in the recordings.
  • RA10 feels bass-light. There is a physical sensation of sub-bass kicks at the back of my neck and in my throat now and then, but most of the time, the bass lines of RA10 are quiet. These are not punchy-sounding IEMs.
  • RA10 does not sound very “hi-fi” or “audiophile.” They lack the airy sensation and micro-details, such as room reverb, to create a 3D “holographic” presentation. These IEMs present the main content of the music correctly, and that’s it.
Looking at the graph, you can see the causes of these impressions. RA10 has an almost flat lower midrange (250Hz to around 1kHz) and an Etymotic-like upper midrange (ear-gain region, about 1kHz to 3kHz). This overall structure of the tuning creates a sense of lightness and correctness in the midrange of RA10.

Despite the Etymotic-like tuning, RA10 is “mild” even when compared to Moondrop Aria and Blessing 2 because of the deep valley around the lower-treble (5kHz), where note attacks reside.

The “bass-light but still has some kicks” feeling of RA10 can be explained by the boosted sub-bass (“kicks”) without the corresponding boost around mid-bass (125Hz, the “punch” region). The lack of “hi-fi” sound can be attributed to the lack of response in the upper treble (above 10kHz).

Alright, enough with the geekiness. How does RA10 compare to some other IEMs? Firstly, RA10 sounds less warm and muffled compared to Moondrop Aria. The note weight is similar to Blessing 2 at a glance. However, in A/B tests, I found that RA10 **highlights female vocals and high-pitched instruments more than Blessing 2. **

So, what is the conclusion? On the one hand, I don’t feel anything when listening to RA10. On the other hand, RA10 sounds correct, and its tuning is elegant, like the Westone MACH 10 that I reviewed a while back. So, similarly to the Westone IEM, I rate RA10’s tonality 4/5 - Good.

Resolution, Detail, Separation: 3/5 - Average​


Resolution is a fascinating subject due to the difficulty of pinning down what it really is. To me, the resolution is closely tied to how many quiet and minor details you can hear. Of course, if you turn the music louder, you can spot more details. However, you can only turn up the volume if the tuning does not have random peaks that stab your ears and mask minor details around them. Moreover, you can only hear details if the drivers manage to separate them rather than presenting a blob of sound. Earphone DIYers very well recognise this “true resolution” difference between drivers.


Let’s consider two aspects of resolution separately using the ever-vivacious One-winged Angel. Firstly, let’s analyse the micro details and texture of the instruments in the first two minutes of the recording. RA10 sounds slightly more detailed than Aria (3/5 - Average). By slight, I mean I needed to A/B multiple times and twisted my ears to pinpoint the differences.

For instance, RA10 reveals the reed sounds of clarinet and oboes more clearly. Other noticeable differences are the amount of texture and details that I can hear in the choir (especially around 1:35) and the claps from 3:40. I feel that these differences stem from the tuning, particularly the blanket of warmth that covers the midrange and masks micro-details of Aria, rather than the resolution of the drivers.

Moondrop Blessing 2 (4/5 - Good) presents a significant step up over both RA10 and Aria. From the first musical phrase, it is immediately apparent that Blessing 2 is more nuanced and micro-detailed in the midrange. The reed sounds of clarinet and oboes as well as the tremolo sections of violin are easily audible. The improvement of Blessing 2 is more than just the sharpness of note attacks. It is about the subtle details, such as the bow scratching against the string, the resonance of the violin body, and the airy sound surrounding the notes. The martele bowing at the beginning demonstrates these points clearly. Next to Blessing 2, both RA10 and Aria feel truncated, like a layer of information is lost.


Secondly, let’s analyse the separation of instruments and vocals when the music gets busy, from 2:30 onward. Aria feels duller and denser. Instruments are less separated compared to RA10. The thinner midrange of RA10 makes the instruments seem more detached. Notes attacks of RA10 are sharper.

Again, Blessing 2 is a clear step up compared to RA10 and Aria. With Blessing 2, all instruments are separated and layered rather than mushed together, making it easy to follow individual parts. Such the ability to clearly render dense music is the indicator of the actual resolution. Thinning out tuning and boosting treble can improve the perceived clarity. Still, these tricks would fall apart when many elements of a mix overlap.

What’s the conclusion? RA10’s resolution is perfectly adequate for listening, but noticeably one step below good performers. I couldn’t help but yearn for a little more detail and separation. **3/5 - Average. **

Percussion Rendering: 2/5 - Below Average​

Percussion rendering reflects how well the tuning and technical performance of an IEM work together to recreate realistic sound of a drum set. Good drum hits have a crisp attack (controlled by frequencies from 4kHz to 6kHz), full body (midbass frequencies around 200Hz), and physical sensation (sub-bass frequencies around 50Hz). Good technical performance (“fast” driver) ensures that bass notes can be loud yet detailed. IEMs that cannot control bass very well tend to reduce the bass’ loudness to prevent muddiness.
Based on the description above of the tonality, you might already guess that RA10 is not a good performer in this aspect. But for the sake of completeness, let’s analyse some test tracks.

The first test track is Dragonborn. I mainly focus on the rumble of the opening phrase. Aria (3/5 - Average) shows a strong bass rumble. After every “thump” sound, you can feel a rumble “brrr” at the back of your neck and in your throat. That’s an indicator of sub-bass. On the other hand, RA10 has little to no rumble. **It only renders an unenthusiastic “thump” sound, and that’s it. **


The second test track is Despacito. This track calls for big, bold, “dirty” bass to satisfy the drops throughout its chorus. Again, Aria produces noticeable bass punches and rumble. The bass drops have decently sharp attacks, better than I remember (showing how much one should be sceptical of impressions from memory). However, the texture within the bass feels overly smoothened, making the bass notes feel big but blunted, like punching a pillow. But at least the bass is there.

With RA10, bass drops are there but faded behind the midrange. Because the bass is quiet, it feels snappier than Aria. However, when I listen very carefully, I find that the quality of the bass is the same. RA10 feels snappier simply because its bass is quieter, thus disappearing faster, thus “snappier”.

Despite my usual complaint about the texture and detail of Blessing 2’ bass (4/5 - Good), it is still one big step ahead of Aria and RA10. The bass extends deeper, bass notes are more precise, and every drop is more satisfying.

Out of curiosity, I dug my E5000 (5/5 - Excellent) out for an A/B test. This bass canon stomps all of them (when powered by a desktop DAC/amp).

Conclusion: 2/5 - Below Average. The bass quality is barely average, and the quantity is insufficient to render percussion instruments and bass with any gusto. At the same time, it lacks the sharp bass attacks of BA-based IEMs. If you don’t like bass or your library does not need bass, you might enjoy this presentation. For me, this performance level needs to be improved.

Stereo Imaging (Soundstage): 3/5 - Average​

Stereo imaging or “soundstage” is a psychoacoustic illusion that different recording elements appear at various locations inside and around your head. Your brain creates based on the cues such as the loudness and phase differences between the left and right channels. Most IEMs do not differ significantly, nor can they compete with headphones or loudspeakers. However, some IEMs offer a more spacious soundstage than others. Best IEMs can create multiple layers of sound from closer to further away and make some instruments float slightly above your head.

RA10 sits closer to my eardrums and does not have a lot of vents. It does not have a deep bass response or extended treble. Therefore, it is evident that RA10 does not have a good soundstage.

Let’s analyse my favourite test track: Synchro (Bom-Ba-Ye). We focus on the first minute of the recording. Aria (3/5 - Average) sounds is noticeably wider than RA10. The hand claps of RA10 shape a soundstage that is strictly in my head, whilst Aria places the claps slightly outside my head. When the orchestra comes in around 0:15, again, Aria paints a broader picture that extends further outside my head, whilst RA10 keeps everything mostly inside my head.

Aria and RA10 fail to project a 3D soundstage with layers and complexity, but they fail differently. Aria presents a wall of sound where all instruments are compressed onto a shallow but wide layer. On the other hand, RA10 presents the soundstage as a blob of sound within my head. The stage has depth, meaning instruments can appear (slightly) in front of me. Still, it’s hard to pinpoint and separate the closer and further away instruments, so the sense of layering could be stronger.


Let’s try something unusual by analysing the soundstage of these IEMs in a video game. For this test, I use CSGO gameplay footage. RA10 is noticeably better than Aria. You can imagine the sound of RA10 as a small circle within your head. You can pinpoint the direction of gunshots within this circle. You can also identify distance, even though such a task is rather difficult due to the small soundstage pushing everything nearer. On the other hand, the Aria can only tell you whether the sounds come from the left, right, or centre. Moreover, anything that happens at the centre feels very closed in.

Conclusion: 3/5 - Average. Mostly in the head soundstage but with decent depth and imaging accuracy.

Source Pairing​


RA10 is not easy to drive.

What does that mean? It does not mean you cannot get loud sounds from these IEMs. Yes, these IEMs require extra volume compared to others. However, any decent dongle can get these IEMs loud with plenty of volumes left to turn up.


The problem is that you might get only some of the crispness and decent soundstage performance I described. When powered by the Apple dongle or even the AP80 Pro X music player, RA10 sounds denser and more compact. Using something like Fiio KA3 would flatten the soundstage, as it is how KA3 sounds. Using a source with a “desktop effect” like G5, Shanling M6U, or a real desktop DAC/amp can make everything wider and more separated. As I did all of my A/B tests with K7, I have already pushed RA10 to its limit.

Since DAC/amp is a questionable topic, let me rephrase myself. I’m not saying that you need to buy better sources to make the most of RA10. I am trying to say that dual-ESS DAC dongles might not give you all the technical performance I described in this review. Fortunately, the tuning and comfort remain intact.


As IEMs get chunkier and more uncomfortable, it is refreshing to see a new release with micro-drivers and tiny shells. It’s fortunate for listeners with smaller ears that RA10 is also a competent IEM. If you are after a small and comfortable IEM for resting or watching random YouTube videos, RA10 is worth consideration.


  • Small and comfortable shells
  • Tonally correct
  • Competent level of clarity and detail
  • Good imaging accuracy
  • Weak bass response
  • Small soundstage
  • They don’t look as good as the marketing materials


Headphoneus Supremus
The Rule Follower
Pros: Weighs maybe even less than 2 grams, my scale doesn't go that low
Super comfortable due to size and weight
The perfect sports IEM, my friends say
The perfect running IEM, my friends say
The perfect sleeping IEM, my friends say
Comes in a choice of three colors, green, orange or white
Amazingly careful sound signature following a set of rules
Fast, yet warm and friendly
Big sound from a small size
Comes with carrying pouch
Perfect to take with you 100% of the time, all the time
Fits in shirt pocket
Fits in a purse
Relatively nice note-weight
Careful warm, yet fairly detailed response
Not forgiving of sub-standard quality files
Absolutely honest to file quality, due to a style of neutrality
Cons: Could by chance be actually too small
Slightly short nozzle length, requiring longer ear-tips
Not forgiving of sub-standard quality files
Powers off a phone, but doesn't get to ear-shattering volumes
Slightly hard to drive
Below average soundstage
Some effort may be needed to find the right ear-tips
Absolutely honest to file quality, due to a style of neutrality
The RA10
Near Field Audio

6mm micro-dynamic

NF Yang CEO of Near Field Audio says that the RA10 follows rules. Frequency response curve rules, ergonomic rules and industrial design rules.



NF Audio RA10 follows all the rules
At the same time the RA10 looks like something unique and original? Does the RA10 look like a different style of IEM to you? Let’s back-up for a second and imagine getting the RA10 as a gift. You don’t know what it is. You see this photograph on the box that shows the IEM, and you know it’s an IEM, still you haven’t really seen it yet. The photograph on the box is representing one of the three colors it comes in. There is white, all white, this orange and a pea green. Imagine opening the box and seeing the RA10 for the first time. I will guarantee you it’s pretty much going to be the smallest IEM you have ever seen. It’s definitely one of the smallest I’ve ever seen, and I have seen a few IEMs. This smallness has an incredible value, due to the size of the IEM and the way the cable works, it’s incredibly comfortable, not only that, it weights roughly 2 grams…….2 grams. It may actually weight less, but these are the limits of my high-tech food scale here at Redcarmoose Labs.

Just for fun, I did something I never do with an IEM……I went out and found some friends to try the RA10 out. Yep…..I simply visited some friends and brought the RA10 along with me in my pocket. I mean, my friends humored me…….or at least they went along with my market study. People it turns-out really like to try new stuff and give their option. I assured them the ear-tips were just cleaned, and I became kind-of an accomplice (with them) to this journey of discovery. Truly I can tell when my friends are sincere, or if they are laughing and have that faint smile on, you know the fake smile that reveals they’re joking. So my first victim was this 28 year old female, who just happens to work for I playfully said…..hay what do you think of these? I had them in my pocket and the first thing I got was a smile……not because of me, or anything to do with what my processes were. Well, maybe it was me………whatever? She was truly smiling at the color of the IEMs, and the shape. She was inquisitive as to how they would sound. But most importantly she was honed in on the weight and size…….not only that, but the cable feel and texture, the way it handled. And low and behold she was actually in the market for new IEMs……at least she said she was anyway. Then I got my first positive suggestion, this was truly surprising to me………she said I’m a runner and these are totally perfect for the style of activity I’m involved with. The way they fit was incredibly special…… special that a sale was made……..I mean she just wanted to take them home. But I told her that, sorry you have to buy a pair, you can’t have this set as I’m demoing it and have other folks to try them out on. So……just like that…………just like that I had a buyer. Why? Probably because they are cute looking, non-assuming looking……and they look like children’s toys. In fact, she never asked how much they cost, or anything about fidelity? She thought they sounded great…….literally, most “normies’ aren’t concerned with the over-all sound that much, I mean they are, but if a product produces a desirable sound then the deal is done.

So maybe these rules here are being followed and adhered to, as the RA10 got their first customer! Next I had to meet my other set of friends across town. Seriously my friends all know I write reviews, and seldom do I just show-up with bright colored wild-shaped IEMs! Yet I am truly interested if they like them or not! So here it goes………a visit from this IEM madman………So here I was, at a different location, trying my luck on some other unsuspecting future customers. Truly this is starting to become fun, some kind of post-covid style of gregarious interaction, some kind of new avenue for me? I’m not sure, as this has never (quite) been attempted in such a fashion or…… least by me it hasn’t?

The first question I got was do they come in other colors………why in fact they do, was my response. I pulled out my phone and showed the different colors available. The next sentence was, I would love to wear these all day. And I had to agree that they seemed to fit really good and I could also wear them all day. In fact they are so small they almost don’t even look like IEMs… almost can’t see them. Where the orange color seemed to help if you set them down, as you could at least identify them to grab them and put them in their pouch. In fact, speaking of the pouch, the draw strings (once closed) are totally a thing I would walk around with in my pocket. Such a size and weight could easily fit in my wife’s purse with-out causing a ruckus. But my friends both said they would be wonderful to sleep in. Imagine that…….I never thought of the sleeping thing, as I almost never sleep with IEMs. So three down…….and maybe I’m on to something…..truly this is the complete opposite of anything I foresaw myself doing. It was fun for me and it was a fun experience for my friends. And while I don’t see the RA10 as the most incredible set of IEMs ever made, they truly are different, an hold a value that people seem to like. Of course I will get to sound later in this review, but as far as frequency response goes, the RA10 goes about its day putting out a super refined version of a harman style response. The sound is a warmish yet detailed and careful display of tones with nothing really offensive or strange. They happen to be slightly more clear than your typical bass heavy consumer-tune $50 IEMs. But my point is, that for once sound quality was almost secondary? Of course it’s important in that you want an IEM that performs correctly……..but because they are plastic they are super lightweight. Because they are shaped the way they are, they are super ergonomic, and because of the cable style, they just deliver their intended purpose as the ultimate sports IEM, or as the ultimate relaxing IEM.

Do you ever have a healing/recuperation day? You know a day just for yourself, so that you can recharge again for the coming week ahead. With whatever that day entails, with whatever relaxation you can come-up with, the RA10 is there with you. Imagine, they are literally the perfect massage IEM, the perfect small IEM to wear when you just want to forget you’re even wearing an IEM. You know, really this talk is almost against everything Head-fi stands for. Low volume listening, IEM lifestyle listening into what could almost be seen as background music listening, if desired. Truly the opposite of focussing on every detail at lower volumes and just forgetting about everything. If this makes any sense to you……if the style of life-scenario makes sense, these are the IEMs for you.

Get them here:

Reasons to buy:

IEM weight, fit and comfort
Polycarbonate construction in choice of three colors
5N silver plated copper cable with great ergonomics
4 pairs of specific Near Field Audio silicone ear-tips in XS-S-M-L
24 dB passive noise reduction
6MM micro-dynamic dynamic driver with 15-30kHz bandwidth
Nice functional carrying-pouch which goes anywhere
Decent authority, better than you may guess
A life-style IEM

Reasons not to buy:
Below average soundstage
Maybe too small to get great fit for some
Takes some experimenting with aftermarket tips
Slightly hard to drive
They work with a phone, but don’t get to ear-shattering volume levels

Model: RA10
Driver: 6mm micro dynamic driver
Frequency response: 15-30kHz
Sensitivity: 102dB/mW
Impedance: 15Ω
Maximum SPL: 125dB
Sound insulation: 25dB
Distortion: <1%
Cable: 5N OFC silver-plated cable
Connector: 2pin 0.78mm
Plug: 3.5mm

NF Audio RA10
5N OFC silver-plated cable
MS42 eartips (XS/S/M/L)



The included extras are nice for the price asked. 6 sets of ear-tips, a 16 page elaborate instruction guide along with the warranty information. Three extra filter sets, if by chance your original filter gets clogged with wax. A fully functional 5N OFC silver-plated cable which handles graciously. And best of all, a cinch-tie carrying pouch. This single feature (the bag) (and how small the IEMs are) was part of the surprise moment upon taking the R10 out and about.

The included cable:

The included 5N OFC silver-plated cable is the cats meow as far as manageability goes. It better be with the whole sports angle this IEM is providing. The last thing you can't have is a thick cable to weigh you down. It's actually very good quality with strain-relief right at the plug. Note the ear-hooks which are nether too aggressive or too laid-back. The weight of the cable plus the IEMs themselves produce a system, a system of balance for out on the go. At the same time the splitter is a giant piece of rubber which goes to take a beating if one ever comes up.........that's topped-off with a solid aluminum chin-cinch which exudes quality. Combine that with a great cable texture and un-tangle-ability and you have the perfect match-up for the NF Audio RA10. The qdc style of 0.78 2 pins means none of the cable mounting mechanism is inside the actual IEM, leaving more room for them to make it smaller. The other advantage here becomes realized as the cable will not go on until the 2 pin is in direct alignment the with both the qdc mounts and covered 2 pin. This set-up generated an extra layer of material outside the plug creating another layer of strength. Such a set-up goes to ward-off against possible side-bends and pin-pull-outs!

If your wondering about the sound lets get started:

Yep, tips are in the sound section because correct fit means correct sound.

I will admit the tips you eventually come-up-with are critical to the quality of sound. Now such a process is always with IEMs, yet maybe more so here. Meaning many IEMs will have a range of being able to fit with a wide range of tip sizes. These nozzles are on the shorter side of the street. In many ways they are like the new DUNU Kima, in that the nozzles are on the shorter side of short. This isn’t a big deal, accept you may need to search to find a specific size of ear-tip to make the IEM work out. Also to help with this search, an extra long tip often seems to add the extra length that is missing from these shorter nozzles! Surprisingly the same exact ear-tip that worked for the DUNU Kim worked with the NF Audio RA10.That’s right, you don’t know till you know as far as fitment goes, meaning you may guess you have fit when you don’t really. And success is finding that specific tip that opens up the musical experience for you. Changes in soundstage, instrument texture and even element positioning can be found improved once you really, really get fit. Basically…..meaning everything changes, yet for many the bass increases, but along with that, you may even find the soundstage to open-up and become populated with the correct imaging……..yep, it’s everything, ear-tips and fitment are the whole thing!

This style of treble is awash with charm, a careful display of much more than the looks of the NF Audio RA10 would have you believe. In typical full-range DD style it’s not the most airy but gets the job done. Thus more mid-trebles and lower treble doses for a rule-following treble. Yep, nothing uneven or splashy going on here.

Probably the most interesting thing is just how honest they are to the music. Meaning get them some good mids and they open-up and parley the experience, get them Lo-Fi and hear Lo-Fi expressed. This may sound like a part of the review which deserves to be in a different section, only maybe not. Meaning the NF Audio RA10 have the ability to sound (relatively) big and offer a filled-out midrange, only get them the wrong files and they come-up short. This is again the rule-following and being true to the source. Some IEMs offer a style of midrange which becomes forgiving when dealt thin and harmonically challenged music. Here is a style of reality, which (just like ear-tips) when catered to, all is well.

While the lows end-up surprising. While still courting a reserved and careful bass experience, the ability is still there if you offer-up something for the NF Audio RA10 to chew-on. Meaning I went searching for songs just to see what the RA10 could do. And every time I looked, and found those true bass tracks, I was gifted with what I would call correctness of form. Playing stark Techno would have you smile and wonder………really, this really. The bumps engage, and much more than you would guess from their tiny size. In fact that’s the secret charm here, that while the stage isn’t the biggest, or widest or tallest, the musicality is here and somehow everything simply falls into place? The word, the single word I have for the bass is warm. Yep, that some IEMs could render all style of bass descriptions, here it’s simply correct and careful. In fact it's the bass (more than anything) that goes to propel the musicality forward. It's this movement that is 100% responsible for the groove. The silly way people look in public when they are shaking their heads for no apparent reason. Well there is a reason.......and that is called bass perception. It's this "pace" that is special and one of my single favorite aspects of the NF Audio RA10!

Maybe the single most important element here? This tune is so carefully chosen in replay, that if any note-weight was missing, it simply wouldn’t work-out in the end. It’s that the NF Audio RA10 walks such a line. That it’s a warm neutral line in that it’s holding just enough note-weight to become listenable and entertaining. It's also this style of neutral that ends being a challenge for bad recordings, because this particular IEM is so honest with the style of file it gets to play, a thinner (old-classic) file all of a sudden will disrupt the party at hand. And soundstage is the same way!

Probably the only thing that kept me from giving this another star. Yes, while there is ample separation and good imaging, the toy-like stage ends being the Achilles heel in replay. If you add-up the physical IEM size and full-on utilitarian properties of what the NF Audio RA10 can do, it’s still great, regardless of the stage size. It’s still a deal, but it will have you looking for your optimal soundstage music to make it all work out. Because when you put together a days worth of wide-stage, well produced music, the NF Audio RA10 is still incredibly fun and a blast. It kind-of takes the wide-stage music and follows the rules with it, joining it to the air with the best of its abilities. So imagine with me an IEM that really does it all correctly, it keeps everything in check, bass tones sculpted well and fast, and the midrange is still entertaining. NF Audio RA10 offers decent separation in the mids, the treble (while not exactly airy) there is good itemization of elements for what it is. In fact many interactive musical items make it out into the stage to secure entertainment, it’s just not the widest stage at its price point.

Probably another one of the best features here. Yep, the way they are tuned they are not exorbitantly technical, but have a sound that seems to roll along, offering interactive pace with all styles of music. Such a careful tune means no frequency is ever getting in way of other frequencies. There is a smoothness that comes from a warmness that interacts with the bass to approximate correct note fall-off. Every note seemly getting out of the way of the next note, music is never jumbled-up in any one frequency range. Such pace is actually the key to many styles of contemporary music, especially music with a beat. But more than that, the bass (while careful) is what separates the NF Audio RA10 from many of its contemporaries. And not due to too much bass, but a heathy balance that just seems to work. The bass notes and drum authorities enter then leave with what you would expect from natural replay, nothing is ever slowed down or askew. Normally this style of pace only comes with treble-centric replay, but here they walk this very carful line where bass is actually heard and appreciated?

The construction is what makes the NF Audio RA10 so unique. Seemingly a children's toy in construction, you don't really get a grasp of what they were going after till an hour passes, when you start to realize that no other IEM does what the RA10 does, or is made exactly the same way. Impervious to impact to a point, Polycarbonate is never used in exactly this form or fashion. The limited pieces during construction means less chance of H20 arriving inside. Plus all the seams are tight as heck, way tighter than your average IEMs. There are still the regular vent holes, one at the base of the nozzle, and the other next to where the 2 pin enters. Strangely enough these vents are about 1/4 of the size you normally see, in fact this style of nozzle vent circumference is a first here at Redcarmoose Labs.





This was as unusual of a review as they come. Seemingly like a toy out of the box, I did a double-take fully realizing just how small these are. Even with studying all the photographs shown on the inter web, there still leaves room for surprise. Yep, these are way, way smaller than you can imagine, even after seeing photographs. Now the thing is, they are unique, unique in that they have a purpose that no other IEM has......the are road worthy. They are built for on the go. Unplug them from you device and plop them into the carrying pouch and off you go. The sound is miles better than many of the TWS IEMs offered today.......these offer a true audiophile experience where ever, and when ever you want!

Meaning, fear that even your smallest IEMs may be too big to fit in your shirt pocket? Maybe you're not allowed to have IEMs at work? These are at the level of spy IEMs, they really are. Are your smallest IEMs too heavy to fit in your shirt pocket, these aren't! Yep, anywhere you can go these go along. Worried about those TWS IEMs falling out of your ears on a motorcycle ride? With the NF Audio RA10 you won't be. It's just there is no weight to them, they are like small pieces of paper in your ears, only they sound better. Want to take a short mid-day nap, go ahead, but you're disturbed by outside noise pollution? Pop the NF Audio RA10 in your ears and forget about everything, music has a way of doing that. The NF Audio RA10 is built strong, way stronger than they look. But because they don't weigh anything, they never totally take a fall, and if by chance they do, being 100% Polycarbonate construction, there is never a worry! Wear them hanging-off your neck and they never get in the way like regular headphones do. They simply go where you go. If by chance these look like an IEM you would be interested in, I have fully disclosed my experience. And strangely even my friends helped-out with this review, only because it was fun and rewarding, and they got to see me again! The music makes you run faster, the music makes you sleep better (if low volume) and music makes you dance to life! If that's not a reason to make a purchase, I don't know what is! :)

I want to thank Penon Audio for the love and for the NF Audio RA10 review sample.

These are one persons ideas and concepts, your results may vary.

Equipment Used:
Samsung Smartphone 3.5mm
Sony WM1Z Walkman DAP MrWalkman Firmware 4.4mm and 3.5m
Sony WM1A Walkman DAP MrWalkman Firmware 4.4mm and 3.5mm
Sony TA-ZH1ES DAC/AMP Firmware 1.03
Electra Glide Audio Reference Glide-Reference Standard "Fatboy" Power Cord
Sony Walkman Cradle BCR-NWH10
AudioQuest Carbon USB
UA3 Dongle DAC/Amplifier 4.4mm and 3.5mm
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Headphoneus Supremus
NF audio RA10. The return of the micro dynamic
Pros: Physically small made for smaller ears.
Highly technical, balanced, resolving tuning from NF audio.
Excellent clarity of sound.
6mm micro dynamic, rarely used in the audio industry
Very comfortable for daily use.
Surprising passive isolation for outdoor use.
Strong light build. Ideal for working out or walking
Small form factor ideal for relaxing.
Perfect gift for loved ones that has a proper sound.
Comes with extra nozzle filters just in case.
Cons: Could be a bit too small for some.
Short nozzle with a small build.
Included tips are short as well made for small people
Absolutely requires aftermarket tips for best fit and sound.
Included cable is what you would expect at the $50 price point
Pastel pea green color.
NF audio RA10

Great sounding $50 IEMs are actually not as many as you would expect. It's a strange price bracket for IEMs as either IEMs are clearly budget oriented which cost below the $50 mark and they start getting more technical and better performing and much more numerous at the $100 price bracket. NF audio has created a completely new IEM using a smaller 6mm micro dynamic with a brand new smaller form all plastic housing.

My fondness for the micro dynamic goes way back in my IEM journey with an IEM that was solely unique at the time the JVC FXC51. Nothing too particularly great about this IEM, in fact it was a neutrally tuned IEM with bass emphasis that had some old school brighter Japanese enthusiast type tuning. It had some wonky treble emphasis but had some astounding details, airy and had a bass end that had some outstanding definition for its price point. I still own these and while newer, cheaper IEMs have easily surpassed these. I have always thought the Micro Dynamic had some serious potential and would love to see more made using the smaller micro dynamic.

Fast forward to today and we have a brand new design from Near Field Audio called the RA10. Not only is the driver they are using unique in that it is a 6mm micro dynamic but so is its housing, its design is most definitely a one off and very unique.

With that I would like to thank Penon audio and NF audio for the review sample of the RA10. They have been burned in for a period of a weeks time and are now ready for evaluation using my sources IBasso DX300Max, Fiio M15, Fiio K7, BTR7, Shanling M6 pro, M5s, IBasso DX160, IFI Gryphon, IFI Signature. If you feel the need to get yourself a set of RA10 you can purchase a set for you or a loved one here at Penon audio.

The design
The RA10 is unique on several fronts. Unique in its housing design and unique in the driver it is using. The RA10 is one of the more smaller form dynamic IEMS i have the pleasure of putting into my ears. Why does that matter? Well for several reasons. Most IEMs are medium in size and it is not uncommon to see a much larger shell design for hybrids and tribrids. I would say a majority of the sizes of universal IEMs are at least a medium. So what about folks that want a smaller, more comfortable shell or if you physically have small ears. The RA10 is small enough to fit folks with small ears. That is refreshing. I would consider my own ear size to be about average medium in size for a male but I personally have friends and family members with some smaller ears that cannot enjoy using a UM Mest or CA solaris in their ears. It is simple, they won’t fit.

I also know many enthusiasts that love to have music playing while they rest. The RA10 was made for you. On the other hand its smaller size also poses a bit of an issue for folks with deeper ear canals as its size also has a shorter nozzle meaning the included tips might not fit well for folks with deeper or larger ears. It is the opposite issue of a larger sized IEM that doesn't fit smaller eared folks. So what to do? Not a big deal, dig deep into your tip canister and find yourselves some double flange tips, I am sure you own a set or two in your big collection of tips. Works extremely well with the RA10. This means the included tips will be a hit or a miss. For me it is a miss as I don't quite get a deeper insertion for a secure fit. So tip rolling is highly recommended on the RA10. Once you do find a good aftermarket tip to use on the RA10. They have a surprisingly decent passive isolation. Rated at 24dbs of passive isolation. That is most certainly good enough to be walking around with and the RA10 makes for good out and about IEMS. Obviously if you take a premium to comfort for IEMs. These are about as comfortable as it gets.


Its looks
If I am to be honest does not exactly scream premium. The colors are pastel? The pea green color my review set is just not all that flattering looking. They also seem to come in all white and and a white with orange color. The plastic housing is sturdy enough and NF audio has always used the protruding 2 pin design for their earphones. I would have liked to see a flat 2 pin design as these are so light, a flat 2 pin would have no issues with having a solid connection on the light shells.

The reasoning for the protruding 2 pin design is due to NF audio history of making monitoring IEMs for stage use. Protruding 2 pins with the cables that goes with them tend to hold a stronger connection to the IEM housing. If you're using them for monitoring use then yes but these were made for music listening. Ultimately the issue with protruding 2 pins is that this design elongates most 2 pin cables. I have a boat load of 2 pin cables but none of them will look right on a protruding 2 pin design is my point. If you do plan on getting aftermarket cables. The QDC type shroud designed 2 pins works on all the NF audio IEMs.

What you get.
The RA10 is a very simple package. You have to temper your expectations as these are being sold at $50 price point. You get a simple soft carry string pouch, a single set of silicone tips. Here is how I know these were made for smaller ears in mind. The set of tips comes with a set of XS or extra small. And finally, it comes with a decent matching silver plated OFC copper cables in single ended.

The sound.
So here is where these will be a bit of a surprise for potential buyers of the RA10. The sound quality of these easily punches above the price to buy a set. The RA10 is tuned for music listening but is one with very good clarity with a technical ability you can never assume you're going to hear from a $50 IEM. The sound balancing is most definitely NF audio house tuning meaning you will get ample upper mids emphasis which casts a clean and clear sound foundation for their tunings. A type of harmon tuning, leaning more toward a reference detailed yet balanced signature. You would never assume the word reference would come up in a $50 IEM but yes these are like a well balanced reference neutral harmon tuned IEMS. Their technical sound is what makes the sound quality of the RA10 a winner in my books.

Is in moderation with nothing that stands out too much, I would say most emphasis is in its lower to mid trebles but has solid detail for the treble end. It's not the most airy of treble notes and has a moderate extension. NF audio treble tunings for music listening have good presence and these guys seem to know when to back off a bit for a more balanced approach to a music listening sound profile. Reason why I mention this is because their monitor series comes a bit bright in their tunings and while the sound profile of the RA10 leans more clean in how it sounds, it does not really encroach on being bright, which is key to longer term listening comfort. The trebles here have a solid footing for its sound foundation with solid macro detailing. Micro level is about average here but nothing that makes the treble out of place, uneven or over exaggerated. Overall the treble is more of an equal footing with the mids vs overstepping the mid bands which can cast a brighter shadow for the sound. The advantage of the micro dynamic is its rigidness vs a larger dynamic. Quick snappy transients are the benefit and here the trebles are clean, details well and has just enough presence to provide a well balanced take on the sound tuning.

RA10 is where the NF audio house tuning comes into play. RA10 has ample upper mids, never seen a graph of the RA10 but if I was a guessing man it would be in the 12db emphasized range for its upper mids presentation. Upper mids can become sensitive to the listener, too much and it can cause a tonal imbalance, brightness, shoutiness and becomes fatiguing. Too little and music becomes soft, lacking attack and bite to be truly versatile. I suppose it will come down to how you like your IEM tunings but I have yet to see an NF audio tuned IEM with moderate pinna gain or upper mids. These sound more harmon in how it is tuned vs having too much in the upper mids. Overall the mids band has a clean sound foundation with a surprising resolution to its sound profile.

Technicalities are actually very good, given its driver tech and implementation and this is the area that seems consistent with micro dynamics. Its detail, timbre, imaging, sound separation with a clean tonal character is all very good especially at the price level except for one crucial aspect that keeps them from being a true higher end sound. It is mostly a sealed IEM with a small venting near the stem and a vent on top of the RA10. The tiny vent holes do two things, relieves any pressure build up in the housing and vents the dynamic for its bass presence. Absolutely zero driver flex of any type was heard on my end.

The RA10, all of it will fit inside the ear with nothing sticking out of your ears. All of it will go into the concha of the ears, with a physical size being as small and compact as it is. This has an effect on its stage. It has a fairly narrower stage, music for the most part is presented mostly in your head, it has a narrower stage than the average IEM head stage. Music is most definitely wider than deep or tall and they certainly don't sound confined. It sounds spacious actually but music comes more intimate than open and has nothing to do with a wide broad sound for IEMs.

Comparative pics. Double flange vs stock short tips.


Dunu Talos next to RA10

I suppose you have to be realistic with a $50 IEM but at the same time. I feel NF audio has a missed opportunity here to really bring out something special in the price bracket. If this exact same tuning and balancing of the sound was presented with a much wider stage. It would be the best sounding $50 IEM on the planet. I suppose NF audio went with more passive isolation for street use vs making the RA10 more of a semi open design for better stage and air for home use. You can look at it that way.

Mids are a strong suit of the NF audio tuned IEM and here the mids clarity is the good type of clarity and we are talking about a clean sound that stays away from overly sharp tones causing fatigue. It could use a bit more meat to the mid bands as it sounds more neutral for the mids than being forward. With that somewhat narrower stage it lacks a bit of depth as well. And that is really a minor complaint about its sound characteristics. Otherwise it's a nicely technical sound profile that gives you outstanding details for the money. Other aspects like sound separation, imaging and timbre are all stand outs for RA10. These sound way more audiophile than any $50 IEM has a right to be.

On a side note. I do recommend a more substantial cable to bring a meatier sound from the RA10. I won't go into to much detail about that but I did try out some of my better cables and just about anything you own will be an upgrade from the cable that NF audio has included. The included cable is fine for the given price point but lets just say the higher resolve of the RA10 benefits huge from a proper cable.

Bass is
Surprising. This 6mm dynamic packs a nice punch with a surprising deep reaching rumble. It's more closer to a neutral tuning than being a bass first IEM. So everything is in moderation here but that bodes well for its overall versatility. The bass end is like accidentally getting that small pepper in your taco that you were not expecting that brings some heat. That makes your brows sweat. Bass end of the RA10 actually turns out to be another strong aspect of the RA10. To be a musically tuned versatile IEM you have to have enough bass to make modern music sound like modern music. Here the RA10 provides a good usable dynamic tight punch for its mid bass and a surprising sub bass extension that works well to complete a sound. The RA10 is a very easy to drive IEM, they are pretty much made for using on a phone. However where these really take off is on something with some power. Bass fills out to a much better degree especially. Bass overall is clearly defined much like its overall sound presentation which shows a consistency in how the RA10 was tuned. The least of my worries on the RA10 tuning is the bass and yes it doesn't have world class texture nor does it convey the most realistic bass presentation but it does provide a tight well defined bass which clearly knows its role in the sound tuning. Bass is spunky enough to actually hear your EDM and hip hop correct. Which again shows some versatility.

Overall the RA10
Is a bit of fresh air from all the new IEMs that are in the market today. You can never assume how an IEM will sound vs how they look. Looks aside, the RA10 delivers where it matters. Its sound quality is among some of the best for its price point. In fact if you would like to introduce a loved one or significant other with some smaller ears something that is properly tuned with good balance, dynamics and class leading clean detailed sound in a small sized IEM form. The RA10 will be a great introduction to proper sound tunings. They will make for excellent media IEM for your phones and tablets. They will make for excellent listening while working out or walking due to how light, comfy and sturdy they are. They will make for perfect fall asleep IEMs as they are extremely comfortable with surprising passive isolation. You don't want to give your old has been used IEMs to your loved ones that barely fit them. You want to give them a new IEM that will fit them with a very good proper sound quality. The RA10 has its purposes. Thanks for taking the time to read.
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The sound quality is excellent and it is using a highly resolving micro dynamic. Excllent for the price especially if you like your IEMs to be comfortable with decent passive isolation.
Thanks for the review. I'll include this IEM in my wishlist.
NF Yang
NF Yang
Thanks for sharing. RA10 is a product that follows the "rules", including industrial design rules, ergonomics rules and frequency response curve rules. Compared with other products of nf audio, this product will be more in line with the market's definition of "scientific curve". Of course, in On this basis, we still maintain the traditional, excellent dynamic and harmonious wave characteristics, which is what we hope to achieve