NF Audio RA15

Short Review: NF Acous (Former NF Audio) N RA15
This is kinda bit late actually, but this unit was given me for a review from a colleague. Given this circumstance, I will give a short yet brief review regarding this.

About the NF Audio (NF Acous) RA15
- All metal dual cavity Dynamic Driver
- Price at $89.00

Packaging

• Packaging feels premium and exceeds expectations within this price range.
• Comes with a white silver-plated 5N copper QDC 3.5 mm cable
• 2 Pairs of Nozzles (Silver & Brass nozzles)
• White storage pouch
• Four pairs of eartips (XS / S / M & L)

Pros:
- Decent level of separation and layering
- Good to above average detail retrieval
- Price

Cons:
- Not for bassheads and treble-sensitive persons
- Lacking instrument separation and layering
- Soundstage is kinda "meh"

Sound Signature: Silver Nozzle
- Bright signature with emphasis on female vocals
- Mids are elevated especially on the upper mids
- Slightly you can hear the "s" and chiming sounds
- Vocals shine throughout with a sense of vocal separation
- Sparkly treble and some level of peakiness

Sound Signature: Brass Nozzle
- Warmer tonality with slight bass improvement
- No marginal difference in terms of mids, vocals and treble

Verdict:
- RA15 can be a rotational set, but considering the IEM competitive market, it can be agreed that it cannot topple or somehow be on-par with the latest IEMs.
- RA15 has a good musicality which you can really enjoy at a price.
- On a personal level, I still find other IEMs like the Truthear Hexa or the Tangzu Yu Xuanji better than the RA15 in terms of tuning.

Audio Geek Turkey Group; I have the nf acous RA15 sent to me as part of the Turkey Tour, I thank them very much
and I will try to convey what they offer as much as I can.

nf acous is a professional iem manufacturer and the products it produces really stand
out with their design, material and musicality.


nf acous RA15 Packaged
Metal structured iems themselves
White silver plated 5N copper QDC 3.5 mm cable
2 pairs of nozzles
White carrying pouch
Four pairs of white silicone tips XS S M L size
warranty documents





Sources Used
Btr 7 Hiby R4 fiio k3


Comfort: When we take it in our hands, the product feels really small and full like a bullet.
A triangular design language with rounded edges has been used. I must say that I had problems
with sealing because it was too small. Even though I used different tips, it only made contact with the silicone tips
as if it was hanging in the air in the middle of the ear cavity and could not stay fixed.
The cable inside is too thin, I would like it to be a little better.
Also, the carrying pouch made of artificial leather does not look bad. It has also enriched the content with MS42 tips.

Bass: Considering the silver colored nozzles that come as standard inside,
it may not be a suitable product for bass lovers.
It looks more pronounced in the mid-bass point.
The sub-basses remain dull. Since the extension of the basses does not extend too much,
it opens up enough stage for the mids.
It is more effective in percussive instruments rather than the basses of electronic music.

Mid: This is the safest part of the headphone, the part that is more prominent than the bass is the midrange.
It has a spacious, clear and detailed, transparent presentation.
Vocals have a nice texture and air.
Female vocals feel more clear in the front,
instrument separation is high, details are quite clean.


Treble: Treble sounds feel bright and energetic with airy presentation.
For example, although nf acous Na2+ has more controlled trebles,
nf acous RA15 is heard too sharply in cymbals
at some moments patience is required for endurance. It can be a bit tiring in long usage scenarios.

Conclusion: This small bullet, which has a clear, quite clean and detailed sound presentation in all music genres,
is quite hard and solid Although it shows very good success in the midrange,
I do not think it is a suitable product for bass lovers, but it may not be suitable for treble lovers either. When the box presentation price is taken into account, it seems obvious that it has stronger competitors.

Disclaimer​

I got this product as a review unit from NF Acous previously known as NF Audio. Except from the review unit I did not receive money or any other necessities to influence the review in anyway. This is my honest and unbiased opinion on NF Audio RA15. My likes and dislikes on this IEM are based solely on my own personal experience. If you're interested in buying RA15 check out AliExpress.

Design & Build Quality​

The design of this IEM is quite minimal and it looks bit stylist in my opinion. As I like silver accessories like watch, ring, bracelet and so on. It has a dark silver tone, with a bit matt texture. The size of the shell is quite small, and it's rare to find such IEMs with compact form factor. NF audio's signature logo's on the center of the faceplate, or rather the outer part of the shell. The center of the shell is pressed down in the middle, which makes me wanna think like, "Did they really heat this thing up just to press it down again in the center? How else am I supposed to think?"

Click to expand...

Jokes apart, the inner side look really well finished and carefully designed. On the inner side of the shell, just below the 2 pin connector, they've used "L" & "R" as indicators. I'd rather prefer red and blue color, which makes it easier to find the right one, before shoving the opposite one in and regrating while putting it back again! However, without the colorful it helps the shell to look as minimal as possible!


The nozzles are definitely worth giving attention. They've provided 2 different types of nozzle. One of them is just silver like the color of the shell and the other one has a golden tone. They've pretty well built as well.


The cable doesn't seem to be anything special. But personally I really liked the feel of it. It's not too robust yet durable. And it's totally memory free. I often used the stock cable over my aftermarket ones. It takes the "W" with it's look and comfort.


I've seem IEMs over $500 providing eartips that are not worth using. Where the RA15 comes with such high quality eartips costing less than one fifth of the price. But get your hopes too high. They don't actually pair well at all. So you still have to stick with the aftermarket ones.


The carrying pouch isn't really that practical, yet quality wise it's really good. I've never seen this type of leather carrying pouch before. Maybe Truthear Gate is similar, it's better and looks cooler.

Comfort​

As you might expect from it's tiny size, it's pretty comfortable for long time usage. It creates a decent seal, not amazing but not bad either. The shell size is so small that it might be too small for people with large ears, although I don't think giants still exist with one or two exceptions. I thought twice about mention two of them I know and end up not mentioning. I'd like to like bit long, so let's not do that.


Even for long time usage I didn't feel any discomfort or any type heat generation despite being metal built. I'm glad for the fact that I've covered this review before winter, I don't have any doubt that it'll feel like an ice cube in my ears, during winter. What a relief!

Sources​

• EPZ TP30


• Moondrop Dawn Pro


• Ibasso Dc04 pro


• Fosi Audio Ds1


• HIDIZS S8 Pro Robin


I highly suggest you to pair it with a warm sounding source, neutral is also fine but never pair it with anything bright or digital like Questyle M15, unless you wanna give up on your ears to achieve the full potential of sixth sense.

Packaging​

• RA15 drivers
• 4 pairs of MS42 silicone tips (XS, S, M, L)
• SPC Cable
• Leather carrying pouch
• 2 pairs of tuning nozzles

Specifications​

Pairings​

Eartips​

• Stock
• DDHIFI ST 35
• Final E (Black)
• Spinfit CP100+
• Tri Clarion
• Kbear 08
• Dunu Candy

Having high quality stock tips out of the box seems like the start of a new Era. But soon as you plug in your player and play a music for less than 6 seconds, you'd immediately realize that the pairing is terrible with the particular IEM. I've saved mine to use them with other IEMs. But for RA15, I liked ST35 and Candy. I believe some things will never change, though I hope they do!

Cable​

• Stock
• Kbear (Inspiration C) 4 core copper
• NiceHCK mixPP

Upgrading cable does changes the sound to some extent, but the sound with the stock cable is already good, if you already have an upgrade cable, it should be worth a try. But no need to buy a separate one.

Sound Quality​

NF Audio RA15 is an IEM with neutral tonality, shows somewhat flat response on most graphs I've checked. The signature is really ideal for editors or people who works on studios or anything related to audio monitoring. As someone who once were serious about gaming, I can assure you these will exceed your expectations.


Anyways, the two nozzles provided with the box seemed useful. They quality of the material seems great, yet be careful while using them, as they might get dent in case you drop the drivers from the 2nd floor. Also make sure to keep them away from kids and pets.


The stainless steel nozzle seems to be the spicier one among the two. Has more air and sparkle on treble. Bass decays faster. Where brass nozzle have more sub bass depth and a bit more Mid-bass impact. More note weight as well. I've personally liked the brass more, as it was more balanced among the two and less bright.

Here's a graph for reference-

Click to expand...

Stainless Steel: Blue || Brass: Orange

Click to expand...

Sub-Bass​

Quality wise the Sub-Bass is there with the good devices. Quantity wise, it's way below average. RA15 definitely has rumble, which it hard to feel. The Sub-Bass has good depth, if paired with the right tips. Overall the bass performs decently on genres like pop, folk, classical and few others. Not an ideal option for metals and rocks in general.

Mid-Bass​

Quantity wise, the Mid-bass seems to have more presence compared to Sub-Bass. Really detailed, lacks body. Lacks a bit of impact on certain scenarios like rock and metals. The texture was adequate, a bit rough on the edges but it was good overall. The Mid-bass is quite speedy on RG15. Definitely nowhere close to a bassy set, but if you're looking for something close to neutral/flat sounding, RG15 might be the best bet for considering the price.

Mid-range​

Initially the mid-range feels super clean and detailed. Every instruments on this region sounds accurate. No noticeable bass bleeding, even with the brass nozzle. Sounds neutral overall. The mid-range isn't particularly thin or thick either. But depending on source it might sound just a little thin if paired with the wrong DAC/source.

Male Vocals​

The male vocals on RG15 is quite detailed. It's not a sweet or warm welcoming vocals, it focuses more on details and accuracy. I can feel the lack of Sub-Bass most of the time. The separation between vocals and instruments were decent.

Female Vocals​

Unlike the male vocals, the female vocals seems to have a lot more energy and clarity to it. Sometimes feels sharp depending on track, but it provides a really energetic and powerful female vocal. Tracks like "Again" by Beverly sounds majestic on them.

Treble​

The treble section of RG15 is quite spicy. Guitars and high hitting instruments sound true to life. Really detailed and sounds bright. From my personal experience, the treble seems more bright than usual. Pairing with a warm sounding DAC might be mandatory here. The upper treble is really airy. Feels quite open.

Instruments​

Instruments on mid-range and treble feels true to life. Guitars have amazing sparkle. Ukulele, violin and any string instrument sound really well. Piano and harmonica sound accurate, lacks a bit of warmth. Drums seem to have low impact, fast decay.

Soundstage & Imaging​

Soundstage of RG15 is really wide. It is well rounded on both width and height. Has good depth. For the price the soundstage feels exceptional. The imaging is quite accurate.

Mobile Gaming​

In PUBG and COD mobile, the RG15 performed really well. Foes firing location can be located pretty easily with them. Even from long distance, where I can not aim without 4X on assault rifle, I was able to get my enemies exact location. Footsteps are pretty easy to notice, whether they're infiltrating from sides, front or back. Grandes after effect sound doesn't stay for long, having a fast decay. Makes it easy for locating footsteps. Whether you're playing causally or competitively, you wouldn't feel the need of having a pricier set.

Why should you consider it​

• If you prefer neutral sound
• If you like clean mid-range
• If you like energetic vocals
• If you're a treble lover
• If you're a gamer
• If you're planning on using it on studio
• If comfort is in your priority

Why should you look elsewhere​

• If you're a bass lover
• If you like warm mid-range
• If you're treble sensitive
• If you don't like energetic vocals
• If you have a purely neutral or bright DAC

Comparison​

Here are some comparison between NF Audio RG15 and similar priced IEMs.

Kiwi Ears Singolo​

Singolo is a much more safer and musical option if you're buying a device for that purpose. Has better bass, warm mid-range and pleasing vocals. However treble is better on RA15 only if you can tolerate it. Gaming experience is much better on RA15 compared to Singolo. For something like editing and studio work I'd highly recommend RA15.

Verdicts​

All in all, NF Audio RA15 is a really great IEM for the price if you're looking for something for your studio, editing or professional gaming. You wouldn't get disappointed. If you're looking for a device just for listening to music, I recommend look for something else.


As always thank you for your attention! Let me know your thoughts on this IEM.


Until then,


Keep on listening ·͜·♡

NF Audio RA15 Review​

Gear Used:
D10 balanced, Hifiman EF400 R2R, THX 887, xDuoo Tube TA-26, Hiby RS2 R2R, EPZ TP50


Sound Signature:

• Lows:
  • The bass is dynamic sounding, but it lacks the impactful thump you might expect from a dynamic driver.
  • The bass dynamics are punchy, but the overall bass quantity doesn't hit as hard as some might prefer.
• Mids:
  • The lower mids are recessed, which causes male vocals to be pushed into the background, making them less prominent in the mix.
  • Female vocals are accentuated too much, giving them a grainy and harsh quality that can be difficult to listen to at times.
• Highs:
  • The highs are bright and slightly sibilant, especially at high and mid volumes.
  • This added sheen makes the overall sound sparkle but can be sharp for those sensitive to treble.

• Comparison: It's brighter than the Simgot EA500 and most of the Simgot lineup, possibly similar to the EA2000.
• Low Volume Performance: Surprisingly detailed and decent at low volumes, likely due to the treble boost which enhances clarity at softer listening levels.
• Bass Dynamics: The bass is punchy and has great dynamics, adding a solid foundation to the overall sound.
• Technicalities: The technical performance is adequate, with most of the perceived detail coming from the treble boost.

Physical Design:

• Fit and Comfort: The small shell size makes it suitable for most ears. However, you might need to use a slightly larger ear tip than usual. If you normally use a small size, consider switching to a medium for a better fit with the RA15.
• Power Requirements: These IEMs have surprisingly high-power requirements, so they might need a more powerful source to reach their full potential.

Gaming Performance:

• Comfort and Detail: The RA15 performs decently for gaming. Its small shell ensures a comfortable fit for long sessions, and the detail boost makes the audio experience feel less congested.

Source Differences:

• Delta Sigma vs. R2R:
  • R2R NOS Mode: Opens up the soundstage, reduces bass thump, and the treble sheen is also reduced, resulting in a warmer sound.
  • R2R OS Mode: Returns the treble sheen, reduces bass, and narrows the soundstage, essentially nerfing the bass impact.
• OTL Tube Amp:
  • Sound Characteristics: Completely removes the treble sheen, opens up the soundstage, retains bass dynamics, and adds a 2nd harmonic sound, giving an echo/reverb effect. This setup sounds amazing but be cautious at high volumes as distortion may occur depending on your OTL.
  • Best Experience: The best sound experience with the RA15 on an OTL tube amp, though not entirely recommended for high volume listening.
• Dongles:
  • Delta Sigma Dongles: Likely to sound similar to the initial impression: bright with a treble sheen, dynamic bass. Tested with EPZ TP50.
  • R2R Dongles: Similar to using an R2R DAP, providing an open soundstage, reduced bass hump, and reduced treble sheen. Portable hybrid tube amps are expected soon.

• OTL Tube Amp: Opens up the soundstage but reduces the tube sound.
• Delta Sigma Solid State: Increases bass very slightly; it might be a subjective observation.
• R2R: Increases bass but slightly reduces the soundstage width gained from R2R.

• Brass Nozzle: Provides a balanced sound with a touch of treble boost.
• Silver Nozzle: Increases vocal presence and adds a bit more spice to the tuning, enhancing the treble further for those who enjoy extra brightness.

NF Audio, now known as NF Acous, has produced a range of products across different price points throughout the years. Among these products are in-ear monitors (IEM) that have been specifically designed with a neutral tuning in mind, and the RA15 is no exception. Achieving an audiophile-level neutral tuning is a challenging task, and not all products are able to do so accurately. Can the NF Audio (Acous) RA15 deliver on this front?
Purchase:

The NF Audio will set you back $90 from your bank account. The RA15 is equipped with a dual cavity dynamic driver, boasting an impedance of 32 ohms, a sensitivity of 108dB, and a frequency response spanning from 10Hz to 40kHz, complete with tuning filters.

HifiGo (non-afilliate link):

https://hifigo.com/products/nf-audio-ra15?variant=45517104251119

Simgot LC7 (non-afilliate link):

https://shenzhenaudio.com/products/simgot-lc7-headphone-upgrade-cable

DUNU Lyre Mini (non-afilliate link):
https://hifigo.com/products/dunu-lyre-mini?variant=45182513479919

Tangzu Sancai Wide Bore (non-afilliate link):
https://hifigo.com/products/tangzu-tang-sancai-wb?variant=44066526298351

TRI Clarion (non-afilliate link):

https://hifigo.com/products/tri-clarion?variant=43552646299887

Spinfit W1 (non-afilliate link):

https://spinfit-eartip.com/#/product/productdetail/104?lang=en

Box/Contents:

The NF Audio (Acous) RA15 is packaged in a black and orange box featuring a picture of the RA15 with branding on the top.
The back of the box displays more images, while the specs are listed on the bottom.
Inside the outer sleeve, there is a black box housing the familiar NF Audio (Acous) CD disc display of the RA15.
Within this box, you will find a square compartment containing the MS42 wide bore silicone tips (XS/S/M/L), a faux leather carrying pouch, the cable, and the alternate tuning filter.

Build/Design:

The NF Audio (Acous) RA15 features a stainless steel shell designed in a sideways teardrop shape. Although compact, they tend to be slightly heavy.
The front showcases an indented faceplate with NF Audio branding, while the back boasts a smooth stepped design.
The nozzle has an aggressive angle and is relatively short in length. This design might pose fitting challenges for individuals with larger ears or those requiring deeper nozzle insertion.

Cable:

The standard cable is rather ordinary in quality. While it has a pleasing appearance, it is notably thin and lightweight. The cable tends to tangle easily and often appears twisted. Many, myself included, are not fans of the 2-pin QDC connectors used. It features a 3.5mm termination.
The ear-hooks are quite aggressive, curling in on themselves. In general, the cable is functional but lacks any remarkable features.

Tips:

NF Audio (Acous) comes with a set of MS42 wide bore silicone tips in sizes XS/S/M/L. While these tips may suit some IEM models, they are not compatible with the RA15 due to their shallow design which barely reaches the filter at the end of the nozzle.
Most users, particularly those with larger ears or needing deeper nozzle insertion, may find these tips unsuitable.

Fit/Comfort/Isolation:

Unfortunately, the fit, comfort, and isolation are sub-optimal with the standard accessories.
The ear-hooks on the stock cable are overly aggressive, causing the RA15 to be pulled out of my ears.
Additionally, the shallow-fitting MS42 tips fail to seal properly, resulting in nonexistent isolation from surrounding noises.

Consequently, I could only tolerate wearing them for approximately 5 minutes before becoming irritated with the entire experience.

Alternatives:

Fortunately, an alternative cable and ear tips can enhance the inadequate fit, comfort, and isolation problems. I discovered that using sturdier cables with a moderate level of tension improved the stability of the RA15. Additionally, longer tips compared to the shallow MS42 tips not only aided in securing the fit but also in achieving a proper seal, resulting in effective noise isolation. An additional point to consider is that broader bore tips contribute to a more spacious sound, while narrower bore tips enhanced the bass and upper mids/lower treble.
I found that using either the DUNU Lyre Mini or Simgot LC-7 cable with the TRI Clarion, Tangzu Sancai Wide Bore or Spinfit W1 tips significantly enhanced isolation. While the RA15 may not excel in this aspect, with different tips and improved stability, they are likely to block out approximately 55% of external noise. This will dampen louder noises like coffee grinders, vacuum cleaners, and loud vehicles, although not completely eliminate them. In terms of comfort, there was a remarkable improvement, as I went from feeling frustrated after 5 minutes to being able to enjoy a listening session for about an hour before any discomfort arose.

Source Pairing:

When using the NF Audio (Acous) RA15, you will quickly notice that they are easy to power but very picky with the sources they are paired with. The RA15 has an impedance of 32 ohms and a sensitivity of 108db. I found that all the USB-C dongles I tried could easily drive the RA15 to high volumes, but many of them produced a sub-optimal listening experience due to their neutral or analytical sound signature. The RA15 delivered a much more enjoyable sound when paired with a warmer source. Whether connected to a desktop setup or a Digital Audio Player (DAP), the RA15 performed adequately, emphasizing the preference for a warmer source pairing.

Tuning Filters:

NF Audio (Acous) provides two tuning filters for the RA15.
The stainless steel (Bright) filter is pre-installed, while the brass (Warm) filter is included in the package. These filters significantly alter the sound characteristics of the RA15. The bright filter enhances the mid and treble frequencies, while reducing note weight, resulting in a colder and more direct sound profile. On the other hand, the warm filter enhances note weight, adds some bass impact, and softens the directness of the mid and treble frequencies.

THA Review Process:

https://www.thehonestaudiophile.com/post/honest-audiophile-review-process

THA Terms & Definitions:

https://www.thehonestaudiophile.com/post/the-honest-audiophile-s-terms-and-definitions-guide

Some Gear Used to Review:

Peridioc Audio Rhodium

Hiby FC3

Hidizs XO

AFUL Snowy Night

Tanchjim Space

Fosi Audio DS2

Aune Yuki

Fiio KA17
Fosi Audio DS1

Hiby FC4

Hidizs S8 Pro

NextDrive Spectra X

xDuuo XA-02

Mytek Liberty DAC ii

Fiio K9 AKM

Fiio K19

Hiby R5 Gen2

MuseHifi M5 Ultra

Sonic Impressions:

What is the sound presentation of the NF Audio (Acous) RA15? All sound evaluations were conducted using the default cable, the brass (warm) tuning filter, and the Spinfit W1 ear tips.

Bass:

Upon first listen, I suspected that the lack of bass I perceived was due to an inadequate seal. Having tried different cables and ear tips, I proceeded to listen further but remained underwhelmed by the bass. The bass lacked impact, depth, and enjoyment. Upon switching to the brass filter, the bass slightly improved. My initial disappointment with the bass, particularly with the bright tuning nozzles attached, persisted. If there is warmth in this bass, it is not readily discernible when listening to any track. The warm nozzles emphasize mid-bass, but the response feels shallow and constrained. The lack of sub-bass results in a feeling of insufficient depth and authority. While the bass is defined, it lacks fullness and impact. With the warm nozzles, the bass is somewhat present and kinda satisfying, yet it often feels restrained. It strives for quality over quantity but does not excel in either aspect.

Mids:

The midrange is characterized by its cleanliness and attention to detail. Instruments and vocals are able to shine with fullness and clarity. While the midrange is more prominent than the bass and exudes a high level of energy, the upper-mids stand out with their vibrant energy, bordering on being overly bright and sibilant. Keep in mind that this impression is made with the warm filter; if you prefer a very forward, lively midrange, you might want to experiment with the stainless steel (bright) filter. Despite its idiosyncrasies, the midrange offers some positive aspects, delivering an engaging and energetic listening experience for its price point.

Treble:

Irrespective of the type of tuning filter in use, the RA15 consistently displays vibrant, intense treble. When utilizing the warm filter, the vibrant, intensity is primarily concentrated in the upper-mids and lower treble. Conversely, when employing the bright filter, the brightness and intensity spread throughout the entire treble range. The treble is not suited for those seeking a subdued experience; it is forceful and assertive with the bright filter, while it becomes more enjoyable with the warm filter. In my opinion, the highs are more listenable with the warm filter, as the tone remains vibrant and intense but the peaks are slightly more controlled.

Technical Abilities:

The NF Audio RA15 impresses with its sound stage capabilities, offering ample width to easily showcase the nuances of different venues. The depth of the stage enables you to hear multiple rows in, while the layering provides sufficient air and space for each instrument and vocalist. Imaging accurately tracks from side to side, although it may not be the most precisely focused like a laser pinpoint. Detail retrieval is really good for the price, you won't miss anything even if you aren't exploring new details. Resolution of the details is top notch for the price. However, the tone and timbre lack naturalism; the note weight is thin and light, the heightened midrange and treble make the tonality seem artificial and strained, resulting in a lack of natural reproduction of instruments and vocals.

vs Tanchjim 4U:

The Tanchjim 4U with the natural tuning filter offers more accuracy and naturalism in tone and timbre, along with increased body and note weight. It exhibits reduced aggression and elevation in the midrange and treble, while delivering more impactful bass. On the other hand, the RA15 boasts a broader soundstage, comparable imaging and layering, and slightly superior detail and resolution. The 4U provides three enjoyable tuning filters - pop, atmosphere, and monitor - in contrast to the RA15's bright filter, which is very displeasing to the ear. In general, the Tanchjim 4U offers a more accurate, natural sound compared to the RA15. The Tanchjim 4U serves as an affordable stage monitor, while the NF Audio RA15 lacks a clear identity..

Conclusion:

Achieving an audiophile-level neutral tuning is a challenging task, and not all products are able to do so accurately. Does the NF Audio (Acous) RA15 deliver on this front?
The NF Audio RA15 stands out as an intriguing IEM due to its remarkable technical prowess and lively midrange and treble. However, the engaging and energetic sound presentation leads to an aggressive and tiring listening experience, lacking in the natural rendering of instruments and vocals. While adjustments like cable changes, ear tip variations, and equalization can be made to tailor the sound to be more listenable, one may question the need for such modifications. Although the NF Audio (Acous) RA15 may be well-received by some, it did not resonate with me personally. While I acknowledge the positive aspects of the RA15 such as detail retrieval, resolution, stage width, depth, and layering, I find its tonality and aggressiveness to be overwhelming for my taste. If you seek a more balanced and natural sound, there are alternative choices available.

I am Dave the Honest Audiophile. Thanks for reading, and I will catch you in the next one. Don't forget to enjoy the music and that honesty is the BEST policy!

I am not a professional sound engineer, producer, musician, or vocalist, etc. I have not done any scientific research, measurements, or in-depth testing of any kind; just my own listening, comparing and internet reading/research. I have limited, real-life experience with recording, mixing and mastering gear. I have been involved since my teenage years with various churches as an amateur sound booth technician.

Please take these thoughts, opinions and reasonings as just that, my honest audiophile thoughts, opinions and reasonings.

Specifications :
Driver Type: Dual-cavity dynamic driver with dual magnetic circuit.
Frequency Response: 10Hz – 40kHz.
Sensitivity: 108dB/mW.
Maximum SPL: 125dB.
Impedance: 32Ω.
Distortion: <1%.
Sound Isolation: 25dB.
Jack Connector: 3.5mm SE gold-plated.
Capsule Connection Type: QDC 2 pin.
Cable Type: 5N OFC.
Dimensions: 150x132x50mm.
Overall Weight: 160g.
Starting Price: 89$.

Intro :  This review unit was sent to me by Sonic Mantra. Thanks to them for giving me the opportunity to evaluate this product and also special thanks to NF Acous. I'm not a professional audiophile, so I hope you can overlook any small mistakes I made. Thanks!

Bass :
The bass was not significantly emphasized, but it was high in quality. The MS42 ear tips enhance the mid-bass. The bass has good texture and speed. The iem can be called as more mid-bass focused rather than sub-bass. But it's not like that sub-bass isn't feel able or recessed. The mid-bass has a good punch and thump. There is a clear distinction between bass notes. However, the sub-bass felt a tiny bit dry to me.

Mids :
The midrange is the star of the show. It stood out with pleasing and clean vocals. The vocals sound fuller. Both female and male vocals have good energy. In some tracks, there was a tiny bit of harshness, but overall, the vocals were very enjoyable. The positioning of vocals was neither too forward nor laid back. There is a small peak in the 5k region, but it doesn't make it shouty at all. The timber of the midrange was natural and accurate.

Treble :
The treble was energetic yet non-fatiguing. It provided good energy in rock and metal songs. The treble was airy, and detail retrieval was excellent. In the golden nozzle, the treble feels dry, but in the silver nozzle, there is enough energy in the treble. The brilliance area isn't muted like other iems, allowing for an excellent presence of micro details and resolution. I didn't notice any sibilance or harshness in the treble.

Convenience :
The build quality is solid, and the design looks minimalistic and premium. The compact shell allows for comfortable use, although it may feel a little bulky at first. But there is a chance to get used to it. However, the stock MS42 ear tips bore feels a little tough.

Comparison with Simgot EA500LM :
The Simgot EA500LM has a more fun sound, while the RA15 is more balanced, allowing for a better overall listening experience. In the bass section EA500LM's sub-bass has more rumble. All the other hand, RA15's mid-bass has more kick. The vocal energy of the RA15 is more prominent, making it more suitable for all genres. The EA500LM is better for listening instruments. However, the soundstage of the EA500LM is larger, and the depth of imaging is better. The EA500LM's treble is sharper and peakier, while the RA15 contains more micro details without harshness. Overall, the RA15's sound is more versatile.

Nozzles :
The RA15 comes with two interchangeable nozzles. The golden nozzle is dedicated to a warmer sound signature, while the silver nozzle provides a brighter sound with a wider bore, making the sound more open and airy.

Conclusion :
The NF Audio RA15 is a great choice in its budget range for those who prefer balanced sound with good technical performance and want all frequencies to be well-represented. It may not be suitable for bass lovers, but it excels in rock, metal, and instrumental genres. Additionally, it is a good option for sound monitoring and mixing, as it offers an all-rounder, technically superior sound. I didn't find it to be too bright. I've got more satisfaction using this iem with Penon Liqueur Silicone Eartips rather than stock MS42 eartips. So tip rolling is recommended.

Tested with :
- FiiO BTR5 DAC
- JVC Spiral Dot++ eartips
- Penon Liqueur Eartips
- FiiO M3K DAP

Disclaimer:-

First I would like to thank NF Acous for sending this review unit and special thanks to Sonic Mantra (Md. Rohit behind the scene) for arranging this tour unit for me to test it out. I am not an audiophile, just someone who likes audio gears. This review is concluded with my honest takes on this iem.

Box content, build & design:-

The NF Audio RA15 is a single dynamic driver set costing $89 during this review. The packaging was well thought out with the black and orange theme going on on the outside. The unboxing experience was decent. The package contents are the earpieces themselves, a lightweight white oxygen-free copper cable with a 3.5 mm termination, a synthetic white leather pouch, four pairs of NF Audio MS42 ear tips coming in extra small, small, medium, and large sizes, an extra pair of nozzles (brass and steel nozzle).

The earpieces are small and have heft to them as they are metal built with a nice gunmetal matte finish that doesn't attract any fingerprints or smudges. The iems are beautiful and minimalistic with a concaved design on the back of the shells.

Ear tips:-

The MS42 is a great set of eartip with a soft and smooth surface and a short stem, the stem itself is thick with a striped design on the outside. I use the MS42 tips as my go-to with my Letshouer Galileo which I bought separately long before reviewing this iem. But the MS42 tips doesn't go well with the RA15 set due to its short nozzle which causes poor isolation.


I used KZ foam tips, Epro E00 tips, and Zhulinniao Zhu Rythme aka Bamboo ear tips on the RA15. For me, the Epro E00 tips were a better match than the rest with this iem. Sound impressions are based on stock ear tips and I will talk about tip rolling later on.

Nozzles:-

There are two pairs of nozzles, one is brass made and the other one is steel. The brass nozzle is a little bit narrower on the inner diameter whereas the silver nozzle is a little bit wider than that of the brass one. The brass nozzle seems to dampen the sound, especially in the upper midrange and treble. And the silver nozzle makes the iem more energetic. Overall the nozzles give the iem two different types of tonality, the brass one is more lush and smooth, and the silver one is more energetic, exciting and more detailed sounding but somewhat dry sounding. The nozzles also affect the technicality of the iem which I will discuss in the sound section.


Sound:-

The RA15 is a well tuned neutral set with a hint of brightness. The midbass is sightly emphasized. The bass is fast and has good extension. The sub-bass lacks both quantity and quality. The Sub-bass rumble is inadequate. But the midbass is on point both in quantity and quality, it is fast and precise with good noteweight and didn't bleed into the mids. The nozzles do not have a noticeable change in the lows. The brass nozzle gives a little more noteweight and body to the midbass but that's all. The nozzles do not boost or tame down the bass in any way.

The mids are clean, smooth and somewhat forward which is really enjoyable. The Male vocal has enough body and is smooth and soothing. The female vocals are exciting, airy and energetic. The nozzles come into play here. The brass nozzle gives the iem somewhat warm tonality and tames down the upper mids energy. On the brass nozzle, the male vocals sound thick, lush, smooth and the female vocals sound smooth. On the silver nozzle, the male vocals sound clean and neutral. The female vocals sound exciting, energetic and airy. But it sounds somewhat dry and there's some peakiness at the upper mids with the silver nozzle.

The treble region is interesting as the nozzles change the sound a lot here. On the brass nozzle, the treble sounds clean, enough detailed and airy. The lower treble sounds good but the upper treble lacks extension. On the silver nozzle, the treble gets more energetic, exciting, and even more airy. But this time the treble sounds harsh and and dry. Although there's more detail with the silver nozzle, the drawback is it gets unbearable with higher volume on longer listening sessions.

The technicality of the RA15 is decent. The sound stage is just average on the brass nozzle whereas the stage opens up a bit more on the silver nozzle. The stage is wider but doesn't have amazing depth. Layering is good given its price, imaging is good enough with adequate immersiveness. Instrument separation is just above average. This set doesn't have amazing technicalities but has enough for it to not sound too tiny.

Comparison:-

For comparison, I will hold the NF Audio RA15 up against Simgot EA500LM as they are similarly priced and similar sounding (on specific tuning nozzle setup)

vs Simgot EA500LM:-

The EA500LM is more energetic, has more sub-bass rumble, is more detailed in the treble region, and is more technical than the RA15. However, the RA15 has much better vocal and overall better balanced tuning. The upper midrange is more peaky on the EA500LM. Instrument separation is better on the EA500LM and is the better set for those who love listening to detailed lively instruments and don't mind a laid back vocal. But the RA15 is the better overall all-rounder for all genres as it is more balanced and is non-fatiguing for longer listening sessions.


As for source, The RA15 pairs well with warm source which gives the iem more body and sounds lusher. It can also be paired with a neutral source while still being a good all-rounder for the price. Bright sources are not recommended for this set. Tip rolling is recommended for the RA15 as the stock MS42 tips aren't a great match for it. The KZ foam tips fit well with the iem but not everyone likes foam tips. The Epro E00 ear tip tames the upper mids down and gives better sealing and isolation and boosts the lows allowing the iem to give more balanced output. The earhook on the stock cable is aggressive which affects fit with the stock MS42 tips. A hairdryer can be used to shape the earhook to the user's preference and a long stem ear tip helps with the isolation and secure fit.

Conclusion:-

The 80-100 dollar price point has so many options that it's really confusing to choose the right neutral set that can play everything well. The NF Audio RA15 is more than a decent neutral iem which gives better value as an all-rounder. It's more like a jack of all trades but master at none type of iem. It has amazing midbass speed and great vocals with smooth yet detailed treble and an immersive sound. The tuning nozzles can spice things up if you want a different taste. You can enjoy quite fun listening sessions with the NF Audio RA15.

That being said, this set is not for bass heads and treble-sensitive people. For those of you who like detailed treble, smooth vocals, and fast punchy midbass, and are looking for a set that can play many genres well, this can be a good set to consider.

NF Acous RA15 review

I am an audiophile from sunny South Africa. These In-ear monitors was sent to me by NF Acous formerly known as NF Audio in turn for my honest opinion. Having their ten-year anniversary this year Ningfan have gotten customer service, communication and shipping right down to the T. The company has one of the most kind and helpful sales reps I have ever dealt with, and it was a real pleasure arranging this review. If their service is this good, I gather their aftersales service will also be on par. The package took just under 21 days to reach me and that is very good knowing I am on the most southern country on the African continent.



Unboxing

These IEM sell for R1555-00 in my country or $89 in worldview. I feel for the price the packaging and accessories is on par with the price. The packaging differs from the normal Earphones I receive, and I applaud NF Acous for thinking outside the box and being different. The slide on cardboard cover is a bright orange and black with a picture of the RA15 on the front and back. When you slide the cover off you are greeted by the coolest design that houses the monitors. It is round and looks like a compact disc. Very creative thinking went into that. When you remove the compact disc looking part you get your carrying pouch and set of ear tips on a nice little cardboard. There is also a little bank bag with your extra set of tuning nozzles and the usual instruction manual. All and all this were a very pleasant unpacking experience.



Specs

Material- Plastic

NFC Technology- no

Sound Isolating- no

Impedance Range- up to 32 Ω

Resistance- 32Ω

Line Length- 1.2m

Sensitivity- 125dB

Plug Type- Line Type

Active Noise-Cancellation- No

Vocalism Principle- Dynamic



Connectivity

The RA15 is sold in a 3.5mm termination and you can connect it to the usual mp3 players, Daps, Phone, Dac/amp, dongles and laptops. I tested the RA15 with the Hidizs S8 Pro Robin and EPZ TP50 Dac/amps as well as the Hiby M300 and Astell & Kern Ak70 mkii. For mobile use I connected it to my Oppo A78+. I also used it on my Nokia tablet and Laptop.



Look & Build

I love the look and build of the monitor themselves as they are small in comparison to most standard IEM, but they are metal and heavy and that always equates to quality in my mind. They go really flush into your ears and I found them a real pleasure under my motorcycle helmet when I went riding. The driver is a 5U High Polymer Composite Diaphragm affair with dual rear cavities for better bass control. The provided silicone ear tips did not provide a good seal for me, and I battled to get a good fit and the problem is I have very big ears, so I always must use large tips on all my IEM. The cable was not to my liking as it is thin and light and flimsy, and I prefer a heavy and thicker cable. That is just my personal preference, and I am sure it won’t be a problem for others. The little tuning nozzles are little screw on metal parts and gives a premium feel when screwing or unscrewing them on the RA15.



Sound

The treble is the star here and Ningfan describes these as warm bright. If you are a treble lover, you will find immense pleasure in this set. I found the silver nozzle to be to bright and did most of my listening with the brass nozzle witch toned down the treble to a very pleasant and non-fatiguing level for me.

As I battled to get a good seal, I knew I could never evaluate the full potential of this RA15, so I grabbed some sticky ear tips that was sent to me by Azla and man a new world of possibilities opened. On Tin Pan Alley by Stevie Ray Vaughan, which is the roughest alley in town, but the music reproduction was everything but rough. Man, that treble hits you a certain way and when Stevie picks those high notes on the guitar you can only close your eyes and nod your head to the beat. Detail retrieval is very good on the RA15, and I could make out a soft drum roll in the back and the cymbals rounding off the drum part to perfection.

With the Azla Xelatec ii tips the sound signature became very neutral, and I found the sound to be perfect for monitoring as nothing was emphasized and bled into the other frequencies. The synergy with other brands is what makes this RA15 very versatile if modding ear tips and cables is your thing. I just had to upgrade the cable as I wanted to hear what it will sound like on a balanced 4.4mm termination. I got four Linum cables from Denmark for review recently and as Linum cables are made for musician’s on-stage monitors and NF Acous always working closely with bands, I thought let’s put the two together and see if I can better aesthetics at least. What a pleasant journey awaited me.

The Linum cable on the balanced port of the EPZ TP50 added just enough warmth to the sound, and I think it is because the extra power gave a little more control over the dynamic driver. With this Linum cable and the Azla tips I think this set is great for on stage monitoring or for monitoring your mixes. This is also very clean sounding and perfect for your audiophile music collection.

If you want to know a song that was made for this RA15 it is Fading Sun by Terje Isungset. There is a lot of bells, whistles and little details going on which the RA15 beautifully dissects and puts every sound in its own space. There is also some nice basslines and deep rumbling. I was amazed at the bass as I thought this set was neutral so we know now that the driver can produce the bass when asked of it. It also showed me that the Linum cable added a bit of warmth. The female vocals were up there with the best and it was so sparkly but just under fatigue territory.

I wanted to hear a bit of upbeat acoustic guitar, and I switched to How it Feels by Sophie Zelmani. I was overwhelmed by a thick and creamy bassline from the lower notes of the guitar and there is a shaker you can clearly make out to the left.

With the new revelations from the tips and cables I wanted to delve into two of my favorite genres Jazz and Classical. I chose Truth to Power by Black art jazz collective because I know that track has some good dynamic range with sudden surges of high trumpet notes. The trumpet sounded magnificently big, and it is as if this RA15 takes the main instrument and highlights it even more.

For some Classical vibes I obviously wanted to see how the RA15 would handle the piano and violin. Yo-Yo Ma provided just that with Piano Trio No. 7 and the bow skating on the violin snares like an Olympic ice-skater. There is one thing that this RA15 does very well and that is reproduce a piano like it is supposed to sound. The RA15 is perfect for Sunday evening classical listening sessions for a final relax before the week starts.

The sound for me is sophisticated enough to satisfy audiophiles in general and music lovers. I wanted to see if I can extract a little more bass out of these monitors, so I fitted the new sticky tips from EPZ, the m100. These tips bring the treble down a little bit just like the Azla tips but also elevates the bass a little, so I went to my electronic dance music collection and blasted some Bad Ninja with Are You Ready and suddenly, the RA15 shook of her classical appearances and became a lot more modern sounding with great controlled bass. I also realized that after two weeks of use the driver became a lot looser, so I know burn in is real for this monitor.

I wanted to push the boundaries a bit and see if I could ad the metal genre but the RA15 sounded a bit flat on Sepultura- Dead Embryonic Cells so I won’t recommend them for metal.

If we move a bit away from music, I found the RA15 to give me immense tingles on ASMR YouTube and TikTok videos. I also appreciated the vocals on TikTok videos as mostly the bass is very heavy with other monitors. Also listening to Podcasts really stood out.

The soundstage is very wide with the RA15 and there are some 8d music videos on TikTok that are made for headphones that really boggles your mind with these because they play with the direction of sound a lot.



Conclusion

I really think after getting side grade after side grade from companies, that NF Acous brought something different to the table and it really refreshing. Who should buy this? Well, everyone from audiophiles to musicians and music lovers. Also, if you are a tweaker these are for you as they respond really well to tip and cable rolling. The great tuning of this monitor can only be described to the many years’ experience that NF Acous has been in the field of in-ear monitors.

This NF Audio RA15 IEM has been provide for assessment and enjoyment to Audio Reviews Downunder in conjunction with Audio Geeks Brotherhood of Audiophiles tours Australia.
The RA15 is a single Dual Magnet dynamic driver design that sells for between $80 and $90 USD. NF audio provides a soft pouch to carry the iEM and a good set of silicone tips in a range of sizes. The provided cable definitely could be improved as it is lightweight and quite flimsy.

Tested with Hiby R3 contain my FLAC music collection and a Cayin RU6 dac. I used a variety of cables and my preferred Divinus wide bore tips for stage and treble enhancement.



Comfort. The shell is small, and the shell is stepped where it contacts the pinna and ear canal. The nozzle lodges well but the shell does not contact the ear in my case, and you can wobble the shell with your fingers. It just feels less secure than other models but in practice because it is small and quite light it's not a real problem. Maybe on a treadmill?



How does it sound?

I'm hearing impressive treble response with this set and no harshness or sibilance. It's very well done. Details and separation are perfectly adequate and fit well with the balanced musicality of the IEM.
The soundstage is commendably wide and I'm hearing good depth. This is a big airy roomy musicscape that fills your head with clean and open music with commendable clarity.

The bass is rendered with nice balance, dipping into the sub bass nicely and with a decent mid bass drums impact. Some people will prefer a bigger bass sound. And there is an answer. It's called replaceable nozzles and changing to the gold/brass nozzles raises the bass curve with significant depth and punch. Once again not to basshead levels but should satisfy people with a fuller warmer bass boosted sound.

Feed this IEM with some EDM bass and synths such as Rufus Du Sol and the single DD plus the acoustic cavity performs at levels well above its price point. The bass has authority and physicality. RA15 has some effective sub bass. Feed it some rock such as "Change" by The War on Drugs and you get a solid punchy experience, not quite basshead levels but not too far away. Seven Nation Army lacks for no impact or vigour.


The midrange is excellent with great tone and timbre with both male and female voices. Piano sounds authentic with natural decay and guitars are on point. In fact the RA15 sounds so good I keep finding myself in a wee tussle
Because my right index finger keeps wanting to turn it up a notch or two louder to get more (40) Not logical but addictive.
The RA15 is easy to drive at a level of 34 on the Cayin RU6. It's scary how much more detailed and powerful it sounds at dangerous levels (50). Thankfully it's competent and engaging at more sensible levels.
Comparisons

Simgot EW300 Hybrid vs RA15 Single DD.

Bass
Simgot EW300 has good low bass and sub extension. Bass is a little soft in impact.
RA has better defined bass with better timbre.
Midrange.

Simgot EW300 is very natural and full sounding. Female vocals sound great. RA Also sound fine with female vocals. They have more presence and a little more edge to them.
Treble.

Simgot EW300 has gentle treble which blends nicely with the Mids. Never edgy or harsh but good resolution.
RA Has more extended highs which improves the details and top end sparkle. To my ears it does not cross the line of too hot.

Both IEMs have very good stage and separation with the RA15 Leaning more towards a treble head IEM and the EW300 is smoother but with plenty of energy and resolution.

Comparing with the 7Hz Sonus. One DD plus one BA.
Sonus has been around for a long while in the IEM market. Discounted heavily at the moment. Similar sound to the other two but with a more open wide stage and improved resolution yet again. Sonus is more V shaped and has a punchy bass. I'd rate Sonus a step above the other two.


Conclusion.

This IEM should be considered at the top of a pack that includes a lot of similarly priced IEMs such as the Simgot and the Kefine Delci. Audition if possible. I enjoyed my time listening to a range of styles of music with the NF Audio RA15 and gets a thumbs up from me.

NF ACOUS (NF Audio) RA15​

TLDR version on YouTube: TDLR - NF ACOUS (NF Audio) RA15

The RA15 have been sent to me directly by NF Audio in exchange for the publication of this review. They have not made any requests and I will do my usual attempt at being as unbiased as humanly possible in my review.

You can find the NF Audio official page here, although they don’t seem to feature the RA15 on their site: http://www.nfaudio.cn/en/index.html

As always, this is a non affiliate link.

To avoid being repetitive in my reviews, you can find all the info about how I create the reviews, equipment used, how I receive the products and how to interpret my reviews by visiting: About my reviews



Intro…

First let me address the naming here. Who is NF ACOUS?

Well, the IEMs I am reviewing today were sent to me by NF Audio and they are the NF Audio RA15. However, a few days ago, I received an email saying that they have decided to change their name from NF Audio to NF ACOUS.

Personally, I prefer the name NF Audio but it is not up to me and it doesn't really matter in the course of this review anyway but, just so you are aware, NF ACOUS and NF Audio are the same company. I have also left the NF Audio page link above as I can't find one for NF ACOUS.

I reviewed the NF Audio NM2 around 2 and half years ago and, to be honest, I hadn’t really heard anything else about the brand since then. That was until they reached out to me a few months ago asking is I was interested in reviewing a couple of their newer models, one of them being the RA15.

As I mentioned above, there doesn’t seem to be an official page for these IEMs, although they are available on Amazon and via a couple of other online retailers, such as HifiGo, where they are priced at just under $90.

They feature a dual magnet single dynamic driver along with onboard electronics to tune the IEMs and come with two sets of nozzles, offering different profiles, although the differences are not huge, but we will get to that in a moment.




Presentation…

Arriving a a black and orange box, with the IEMs on the cover, we open it to find the CD shaped card that immediately reminded me of the NM2, holding the IEMs. Beneath this we find the accessories, which are 4 sets of silicone tips, the extra set of nozzles, the cable and a small drawstring storage bag.

Honestly there is nothing really exciting in the contents but they all look aesthetically pleasing and, while the cable is nothing to write home about, do their job.




Build and aesthetics…

The IEMs are a full metal build and are rather small. The nozzle is not overly long either, which, paired with the shallow style tips, make for a fit that is not very deep. I found myself opting for the L sized tips and once fitted, they give a good seal and felt very comfortable.

As they are metal, they are not the lightest IEMs but, due to their size, they are far from being heavy. They are a set that I can easily wear for many hours and not feel them in my ears at all.



Sound…

All tracks mentioned are clickable links that allow you to open the reference track in the streaming service of your choice (YouTube, Tidal, Qobuz, Spotify, etc.)

As mentioned, we get two sets of nozzles and the frequency response is different between them, although they are still fairly similar. Here is the usual graph showing them in relation to my preference curve that I post for reference:



Starting off with the gold nozzles, I found them to be rather neutral with a hint of extra warmth in the midbass which can become just a little boom on certain tracks, such as “Breezeblocks”. However, the upper mids do rise to a peak at 5k which, as I have mentioned many times in the past, is not something that I am a fan of. In fact, I find the peak to be painful many times but in the case of the RA15, with the gold nozzles, it is not actually as bad as I would have thought.

Yes, the peak is noticeable to me as I am very sensitive to that range, yet I do not find it to be piercing like I do on so many other sets.

The treble is not exactly smooth but also doesn’t portray itself as being bad or uneven. I find the general sound to be rather neutral with a hint of bright, something that I don’t mind at all. It is only that boomyness of the midbass focus that can be tiring at times.

Swapping over to the silver nozzles, these bring a bit more presence in the upper mids and take away some of that boomyness in the midbass, although it is still there, just that the focus is shifted to the upper mids.

The thing is that the silver nozzles seem to give everything a more fragile and “thin” sound, especially in the upper ranges. It is not that the tuning is completely different from the gold nozzles, I would still say that we are in the neutral bright zone, but things just sound sharper and not in a good way.

Although there is is more presence between 2kHz and 4kHz, I actually notice the 5kHz peak more with the silver nozzles than I did with the single 5k peak on the gold nozzles. This made the listening experience less enjoyable for me personally.

As far as details, they are pretty decent and there is a nice sensation of sound stage also, with things seeming having plenty of space to breath (except for those tracks where midbass boomyness is experienced). The location of instruments in “La Luna” is pretty good and there is nice space between them, although I do find that width is superior to the depth.



Conclusion…

Honestly, it is nice to see brands that are staying loyal to their tunings and not jumping on the bandwagon of whatever is “in season”, yet, I really can’t say that there is a lot of difference between the NM2 and these, 2 and a half years later.

In fact, I think that I personally prefer the NM2 over these due to the lack of peak in the 5k region.

Saying that, with the gold nozzles, I find them to be a pleasant listen and, while they are not my first pick for IEMs, they do have a sound signature that is not commonly found lately, so they may be interesting to those looking for that neutral bright signature.

___
As always, this review can also be found in Spanish, both on my blog (www.achoreviews.com) and on YouTube (www.youtube.com/achoreviews)

All FR measurements of IEMs can be viewed and compared on achoreviews.squig.link

All isolation measurements of IEMs can be found on achoreviews.squig.link/isolation

*NF Audio RA15 IEM Review*

I recently had the opportunity to test the NF Audio RA15, a tour unit received through the Audio Geek Brotherhood group of India. My sincere thanks to Sandeep for arranging this tour for the Indian audiophile community.

I received the RA15 in unboxed condition along with NF Audio Kazoo 1. Honestly speaking I had no idea what this thing was. Apparently it's a musical instrument.After reading about it online, I tried playing it but didn't like the sound of kazoo. Or let's say I couldn't play it well . RA15 comes with 2 tuning nozzles. Out of the box it was equipped with silver ones and they sounded very flat to my taste. I changed them to the Gold nozzles and my further impressions are based on the same.

*Price:* $89

*Build Quality:*
The RA15 is well-made iem with a premium feel. It's small, solid, and looks great, giving the impression of a high-quality product.

*Fit:*
Fit can be tricky with the RA15. The short nozzle makes it hard to get a comfortable fit, especially for those with bigger ears. The stock tips don’t help much, the largest tip also looked smaller to me. The shape of the earhook makes things more difficult. I changed the cable to Faaeal Hibiscus 4.4 balanced cable for better comfort and for the obvious advantages of balanced output for the further impressions.

*Sound signature:*
The overall sound signature is neutral bright.

*Bass:*
The bass is fast and precise, fitting well with its neutral sound. Subbass is more prominent than the midbass when you get the proper fit. Again the tips play a major part. Stock tips were too small, giving a flat sound to my ears. I tried Penon lacquer orange tips but those also didn't help much. Finally I used a decade old Hifiman's soft silicone tips which gave the best fit and ultimately complete bass. However, it lacks the strong impact that some might want.

*Mids/Vocals:*
The mids and vocals sound natural and clear for most of the part but leaning towards bright and occasionally gave a metallic feel. I personally feel that the overall sound lacks note weight.

*Treble:*
The treble is detailed and sharp, adding clarity to the music. It has very good resolution in the highs for the price category.

*Imaging & Soundstage:*
The RA15 offers a wide soundstage, making the music feel spacious. Although it lacks the height.The imaging is clear, with instruments well-separated, which works well for complex songs.

*Conclusion :*
The NF Audio RA15 has a premium build and offers detailed sound with fast bass and clear vocals. If you pass the fit test, you'll experience a technically superior sound.

I can define them as "Balanced and Bright" kind of sound, more than "Bass and treble"...

Tested with:
Ibasso DX170 / 3.5mm
Aune Yuki
Qobuz
Tidal
Sony Walkman NW-A55 (with this just feel a little warmer)
Dunu S&S Tips (Just because the MS24 didn't fit me)

Here we have a $100 usd set of iems, the packaging it’s outstanding very well made and with good quality in general, all the accessories are very good crafted and the quality of the iems its a gold point to them.

The way of NF Audio to make you part of the unbox of their sets its well thinked.
Unbox experience. 10/10

Unboxing:

¡Congratulations for the Designers! sometimes we forgot all the work behind the products that we use everyday.

¿Whats included in the box?
well we have the pair of iems, 4 pairs of eartips (MS42), sound nozzles, and a pouch; we also have an instructions where we read the recommendation to put the iems to burn for 50 hours or more. And yes you can notice the difference between the “new sound” and after those 50 hours.

The build of this iem it's pretty good the body of each iem feels with really good quality, they’re strong with a comfortable shape, but for my hands are a little slippery. The connectors are .78 QDC and feels robust. The nozzles have good bulb but for me are a little short for the eartips that are included, I fix this with the Dunu S&S Tips. I really like the build of those RA15 a lot.

The eartips are really comfortable, but for me with these iems feels really short, so I try them with another iems and are very good. the shape helps to has a good seal and non intrusive seal, so the design of the eartips for me are a 10/10 but I would really valorate if they includes at least a pair of sponge eartips or something similar just for people like me that has a different kind of ears.

Cable its good. Lately I bought a very thick cable that I thought I was gonna love but no; its very heavy and uncomfortable. but the cable that include the RA15 Its “Special” feels very premium for its price and it’s very thin, soft, flexible and light so you can walk with the set with any kind of problems about the weight or thickness. feels Reaaaaally good. The detail “NF Audio” in the plug its a good plus. I would buy this cable for my another sets if there's disponible.



Sound in general (Stainless Nozzle)
I can feel them as Neutral-Bright iem, the sound in Subbass areas is very extended but it also have a good dry punch that you can feel when its needed in the music but it never feels overwhelming or dirty with near frequencies. Mids has good clarity in general, the timbre there, is good for almost all kinds of music, sometimes it can feels a little brighter (for me) but for my surprise with music like “Gojira” or “In Flames” this “Brightness” disappears and let us enjoy an amazing texture in the distortion of the guitars but if the music it’s very fast and intense the male voices could sound a little behind everything. Highs; The air in this area it’s pretty good but it doesn’t feel “regular”, because sometimes sounds really good and sometimes feels harshly.



Sound in general (Gold Nozzles) The sound is very similar in general the only differences is the bass and the treble. The bass feels a little bit faster and deep, and the treble has a lot more air, and feels with good timbre it feels with a little more control, BUT there's sibilances with very sharp guitars and it gets a little distorted, especially if the sound is very high compared with other frequencies. with low music like pop, instrumentals and lofi the control and details its very good and very enjoyable

For this part of the review first we gonna talk about STAINLESS Nozzle (1) an then about the BRASS one (2).

SUBBASS
1- it feels a little dry and with less gain.
2- it feels envolving with short but punchy the timbre its natural and you can notice it could maintain the sound while another parts of the music are still sounding. This frequency always sounds in another plane that is always present. Very natural, warm and with good technics.


BASS
1- I didnt noticed about something different here.
2- Again the sound is natural with a little more gain in this areas, that just feels with a better texture and envolving, never sounds saturated.

MID BASS
1- You can feel here just a little less information, and little less punch. but still sounding very good and enjoyable.
2- Here is a little more elevated and feels fast I really enjoyed this areas because it has the same timbre but feels very good with punchy songs, the texture isn’t as good as in the subbass and sometimes sounds very roundness.

MIDS
1- The tone here its a little more analytical, the emphasis its noticeable, and the information its more. you can start feeling a little bit of harshly sound (Specially if you are very sensitive to mids and trebles with emphasis like me) if you’re not sensitive to this areas you really gonna enjoy the details that you gonna have here with this nozzle.
2- Voices, Guitars, perccusions, synts and almost all the instruments in this area sounds very natural and with a pretty good timbre with slow or relaxed music. with metal surpresively everything has a really good control in general, guitars doesn’t sound harshly and all sounds really good with good definition and here you can start feeling the thransission between warm sound to something a little bit more analytical.

MIDS-HIGHS
1- everything sounds harshly if the music is very fast or if theres femme voices, the change it’s very abrupt, maybe if you’re not very sensitive to these frequencies you could enjoy them.
2- You can start feeling the air in this areas what its very good, BTW the soundstage isnt very wide, i feel it very standard with good details and very good separation in general, everything sounds natural and with a little warm tone, for me feels good and very enjoyable at low volume. this changes extremely with the other nozzle.

TREBLE
1- with this nozzle the accurate in treble its just a little bit better but again if you’re very sensitive to mids and trebles you can feel it brighter and harshly, less than the mids but you can notice this bleeding between both areas.
2- the sound it’s bright and near, all the instruments here fels with good extension and with good sound in general; again its something you can enjoy very much. the sound image its very good but isn’t very accurate. that’s not a real problem because everything sounds very smooth and balanced.



SOUNDSTAGE
1- The bright and details are much more elevated, which is good for some kinds of music like lofi, some jazz or alternative music, i really enjoyed them with these genres, but its tired after a few hours of listening.
2- The soundstage with the RA15 its good not massive but feels very standard focused in the details and the neutral sound, very enjoyable instruments near and far, the pans are very precise and clean, you really gonna enjoy almost all kind of songs with this nozzle.

SOUND IMAGE
1- You gonna ear the same kind of details, the unique difference its in the mids and trebles where you can notice a brighter sound that sometimes could be very tired and harshly.
2-You can ear the differences between every kind of instrument, all sounds good and detailed with good layering. The best part I enjoyed with this nozzle it’s that you can still feeling the punchy bass while everything continues with its own sound. this make the RA15 sounds very clean and coherent.



In conclusion…
I can recommend this set to start in the hobby because you can change the sound directly changing the nozzles, that could give you a “balanced” sound or something more “analytical” for me the best choice it's the balanced ones (brass nozzles). This set works pretty good with almost all kind of music but I enjoyed them much more with genres like Lo-fi and Heavy metal like In Flames, Orbit Culture, Whitechappel and this kind of bands, it doesn't has much sense, because they’re shouty bands but with RA15 the control in general is really good and doesn’t feel any kind of harshness.

I can’t recommend something that hurts me (Stainless Nozzle). But this set with the Brass Nozzle is REALLY GOOD. I gonna let the Brass nozzle forever in my RA15.

The sound with the stainless nozzle I feel it bright with good information but a little harshly for maybe a lot of people, few friends, and people near me feel the same about the kind of sound of the RA15 with this nozzle, btw i think its a good iem with another one.



Youtube Review in spanish:

Introduction

NF Audio is a headphone brand under Shenzhen Ningfan Acoustics Co., Ltd, which was established in 2014.
It has been almost three years since I reviewed an NF Audio model and now I have in my hands the latest IEM under this brand. This is the RA15, an all-metal dual-cavity dynamic transducer all-metal in-ear headphone. The MJC2L-10M driver uses a dual magnetic circuit capable of generating more than 1 Tesla. The mouthpieces are detachable, to achieve two types of tuning: warm (brass mouthpiece) and bright (stainless steel mouthpiece). The ergonomics have been improved with the new R-series and incorporate the high quality MS42 silicone tips. For the cable, transparent strands of oxygen-free silver-plated 5N copper conductor have been chosen. Thanks to the design of these IEMS the RA15s are able to offer a passive sound reduction of up to 25dB. Let's take a look at what this latest model from the brand has to offer.



Specifications

• Driver Type: Dual-cavity dynamic driver with dual magnetic circuit.
• Frequency Response: 10Hz - 40kHz.
• Sensitivity: 108dB/mW.
• Maximum SPL: 125dB.
• Impedance: 32Ω.
• Distortion: <1%.
• Sound Isolation: 25dB.
• Jack Connector: 3.5mm SE gold-plated.
• Capsule Connection Type: 2Pin 0.78mm.
• Cable Type: 5N OFC.
• Dimensions: 150x132x50mm.
• Overall Weight: 160g.
• Starting Price: 89$.

Packaging

NF has not changed much in this respect and the RA15s come in a classic packaging with dimensions 150x130x50mm. The model name is vertically in white letters on the left side. In the centre you can see a real photo of the IEMS. At the bottom you can read that this model belongs to the Music series and the brand logo is on the right. At the top there is the classic flap for hanging. On the back you can see the capsules in detail in an enlarged photo of the two. Also the description of the model in several languages. The specifications are on the side of the box. After removing the outer cover you get to the classic black CD-type mould containing the capsules. Underneath is the carton that holds the MS42 silicone tips. The rest of the accessories are at the bottom of the mould. In summary, the complete contents are as follows:

• The two RA15 capsules.
• Four pairs of white silicone tips size XS*S*M*L, model MS42.
• One leatherette carrying pouch.
• 5N OFC cable.
• Instruction manual.
• Two pairs of tuning mouthpieces: warm (brass mouthpiece) and bright (stainless steel mouthpiece).

The brand's classic, eye-catching packaging. In the past it came in a grey zipped case with the brand's logo. Now just a leatherette pouch. Only one set of silicone tips, even though it is the MS42 model. There is no option to choose a balanced plug.



Construction and Design

The previous NF Audio models I have reviewed had a semi-custom shape, either in resin or metal. This time, the design is different, smaller and flatter and like the best ones, in metal. Without a doubt, it is a very careful and ergonomic design, with an external equilateral triangle shape with very rounded corners. The central part of the outer face is depressed, leaving a hollow where the brand's logo is printed. The capsules are quite thin. At their edge, the connection interface projects outwards. The gold-plated 2Pin 0.78mm connection is inside an oval piece of rigid, translucent plastic. Close to this interface, but on the inner side, the letter indicating the channel is engraved. The model name and the Music series are printed on this first step of the inner side. There is also a hole. There is a second level which forms a semi-cylindrical step. The mouthpieces stand as a third level and there is another hole in their skirt. The capsules are all-metal, with a shiny rough finish. The mouthpieces are interchangeable and screw-on. The warm sounding ones are made of brass and the stainless steel ones offer a brighter sound. Both are protected by a perforated metal grille. The crown has a diameter of 5.8mm, while the middle part is 5mm, the length of the mouthpiece is 4.8mm.
The RA15 cable has a 5N conductor made of oxygen-free, silver-plated copper. It consists of 2 coiled strands, resulting in a soft, shiny, white cable. It is easy to handle and has a Velcro strap. The sleeve of the plug is unchanged from the other models, being cylindrical and grey, except for the flat part where the brand name is inscribed. The splitter piece is a triangular black plastic medal, with the logo on one of the sides. The pin is a metal ring-shaped pin that fits very snugly. The two-pin connector is covered by a transparent, rigid plastic sleeve. The sleeve is angled and has the classic vertical axis separation. The cables coming out of these connectors are protected by a semi-rigid and transparent sheath, which gives them an over-ear shape.
The cable is still the brand's classic cable, but the capsule design has been improved to reduce the size of the capsule. The construction is very robust, the surface is very smooth and the capsules feel dense, yet pleasant and attractive.



Adjustment and Ergonomics

The capsules are really small and thin. The inner side, in three levels, fits very well to the inner morphology of my ears. The metallic surface, subtly roughened and very smooth, enhances the experience of contact with the capsule. The design is very suitable for the projection of the mouthpieces, despite its length and thickness, the insertion can be shallow to medium. The specification claims 25dB of passive isolation. I think the tips have a lot to say about this. But with my large tips filled with homemade foam, the isolation I get is quite high. The cable + capsule set is nice and the over-ear hooks don't bother me.
NF Audio has really achieved a high integration of the new capsules inside the pinna. This allows for a very durable fit, very suitable for daily and outdoor use. Despite the density of the capsules, the weight is not very noticeable and does not cause any problems over the hours.



Sound

Profile

The NF Audio RA15s come with two tuning mouthpieces. The gold-plated brass mouthpiece produces a warmer sound and the stainless steel mouthpieces generate a brighter sound, subtly with less bass and more emphasis on upper midrange, even treble. The sound with brass mouthpieces is somewhat softer, while with stainless steel mouthpieces the sound becomes more vivid and splashy. One could summarise that the profile of both mouthpieces is a V-shaped upper mids oriented, with a bass slightly above neutral. There is a high point at around 5khz, which can be an annoying peak in a sensitive area of the human ear, as well as being conducive to sibilance and other undesirable artefacts. Clearly, excitation at this point can solve problems of clarity and transparency, but in a somewhat contrived way.
The following description has been made with the warmer brass filters. While the comparison will be made using the stainless steel filters.



Bass

All the previous NF Audio models I have reviewed have very good bass. The Plus (+) versions softened the low end too much, while the RA15's fall off halfway in amount of energy. At all times, I liked the low-end behaviour of the NF Audio. The RA15s are no less and hit the low frequencies with firm, tight, concise and dense power. Such characteristics describe a dark, volumetric and deep bass, which becomes greedy and addictive. The bases are precise, with little aftertaste and an accelerated decay that means there is hardly any flavour. However, there is a certain rubberiness and elasticity, without ever sounding boomy. In the very low pure tone test, there is a subtle undulatory character at the low end, combined with a sensory and barely audible aspect. The sub-bass is not too noticeable in presence, but reveals that dark colour that the lower range of the RA15s possesses. As the hertz increase, the power increases, as well as a more natural colour and a purer, more canonical, colour-free behaviour. The overall result is a realistic, dark and deep behaviour, classic of a good dynamic driver, dense and with a good sensory component.
In music, bass is not predominant, but it picks up its prominence when it appears, especially in electronic music. It is clear that the upper treble and midrange are more present in the mix, but their colour, depth and presence proclaim the budding energy of an aspiring bass-lover.
In the heavy, complex bass test, with dirty, unfiltered bass lines, the RA15s handle themselves like a fish in water. They negotiate the difficulties with precision, daring to describe them with skill and in a full and rich manner. They never try to minimise or simplify the bass, but expose it in as much detail as possible, bringing out an ability to interpret the lower range in a reliable, fast, natural and realistic way. In this way, the lowest notes always have a beginning and an end, there is clear distance between different bass lines and the bass layers always feel well layered. Finally, the RA15s know how to distinguish bass from all other frequencies.



Mids

It is clear that, with the permission of the lower area, the V-profile of the RA15s leans towards a certain upper mid-centric tendency. This generates a certain hollowness in the first half of the midrange. There is a mixed feeling of warmth, of an incipient and present base in the lower male voices. But soon there is a kind of emptiness, an absence, and where the more corporeal part of the music should be born, there is a leap towards the high notes, the details and the harmonics. In this way, there is this perception of a sonic gap that can be more or less striking, depending on the songs or musical style played. For the most part, the warmth of the brass filter survives this sensation. Even the male voices can become very prominent and rich, but I never quite get a full, continuous and dense impression of them. The lower strings possess more forcefulness and physicality, while the rest of the higher instrumentation, before reaching the turning point, is discontinuous in its thickness. The positive result is that the brass filter achieves a neutrality in timbre, as well as a more realistic sonority, despite those peaks and flares present.
In contrast, the female voices possess all the splendour desired in the male voices. They are dense from beginning to end, one feels that blend of thickness and finesse that fills them with body, physicality, detail and nuance at both ends. The richness in them is very full. The same goes for the electric guitars, which are piercing, starring and vivid. Admittedly, even with the brass filter, the RA15s border dangerously on sibilance. But I must say that the detail is entrenched beyond a search for a forced protagonism and this confers a double ability: on the one hand, a more analytical sound within a slightly warm line; on the other hand, a shared presence between the fundamental notes and the nimble nuances, which helps to establish a musical balance on most occasions.



Treble

The treble of the RA15s has the classic V-tuning decreasing sparkle, the peak of which is between the end of the midrange and the beginning of the high notes. In the upper range, small peaks and valleys are combined as control zones, alternating sharp contrasts. They do not create an inconsistent zone, but it is not entirely homogeneous, although it will always be protected by the classicism of this frequency response.
Initially, the high notes are very well represented, with that initial crisp sparkle, on both sides of the sibilance boundary. The energy of the high notes is consistent and their persistence is also consistent, which enhances their realism and naturalness, without feeling forced. Stretching the response more horizontally would have been more detrimental and that's why I don't object to the current tuning in this area. The driver is precise enough to spread out details of much higher notes and marry them with that powerful initial energy. Moreover, it is capable of extending with presence into the upper treble, bordering the air zone.



Soundstage, Separation

Despite the brass filter, the stage is wide horizontally. It feels deep and with a good height that gives a certain zenithal aspect to the music, especially in the macro details, which seem to volatilise overhead, acquiring that characteristic gaseous aspect on these occasions. The sound is clean, separated, with a very good level of transparency. It feels uncongested and although the brass filter adds more warmth, it feels more on the side of musicality and a certain softness at the edges, rather than in the density of the mix. The music feels splashy, but the micro detail doesn't quite come through. And it seems odd, in a driver that seems to have a very good level of exposure and informativeness. But, at such a small level, the RA15s are reluctant to appear in an obvious or exposed way.
On the other hand, the image is clear, well positioned, thanks to the distance of the elements from each other, both horizontally and in depth. In this way, the elements are isolated in an enveloping way. The sound does not become completely enveloping, but there is a noticeable lateral perception, even a deep and powerful lower base that emerges from below.



Comparisons

Rose QuietSea

For this comparison I used the Silver filter on the RA15s.
The Rose QuietSea is an IEMS whose initial price was under $100. But, now they are at $50, a bargain if one takes into account the quality of their accessories, possibly one of the best cables in the range, not to mention the zippered case. My least favourite thing about the Rose is the MMCX interface, which I am against because of its poor performance over time. Some of Rose's own IEMS that I have reviewed have been among my favourites, but have fallen out of favour because of the continuous loss of connection due to the MMCX interface.
As I say, the Rose beats the RA15s in terms of accessories, much better cable, 4.4mm balanced plug and zipped case. In terms of design they are not the same, but they are similar in size. Both have a triangular shape, but the QuietSea are more regular, more isosceles-like. The Rose has metal parts along with resin parts, the RA15 is purely metal and heavier. The inner face is the most different, with that thinner edge of the NFs and that triple level. The Rose's are smooth and steeply sloped towards the mouthpieces. The ergonomics are frankly good in both models. Perhaps the lighter weight of the Rose tips the balance in their favour. But the RA15s, being thinner, fit better in my ear, and the fit in relation to the tips used is better. The Rose's oval mouthpiece is their main flaw, something that can ruin the fit. So, the RA15s, finally, are safer in this respect.
The Rose are easier to move and more sensitive.
One thing that can be observed in both frequency responses is that they are identical up to almost 1kHz. Then, the upper midrange and early treble are differentiated by the QuietSea's double peaking in front of the RA15's greater upward linearity. Then, the Rose's seem a bit more excited in the second part of the treble.
Both are IEMS with 10mm dynamic drivers. The difference in frequency response in the bass is in the behaviour of the two sets. The behaviour in the very low frequency pure tones is highly similar, with a very similar character. The loudness is also similar. Perhaps the RA15s have a little more darkness, less colour and subtly more depth. I also think they have a bit more presence and punch in the mix. The sound and behaviour of the bass is very similar in both models, but the Rose's sound more neutral overall, while the RA15's area has more weight.
In the first half of the midrange the sonic equivalences continue. The neutrality of the Rose in the lower range seems to free up more of the central range. This gives the male voices a bit more prominence, although the timbre and behaviour is very similar. On this occasion, the greater weight leans towards the QuietSea, providing a little more richness in this first phase.
In the second midrange phase the female vocals of the QuietRose feel more transparent, leading, with more emphasis and energy. It seems that the 2khz peak can provide more emphasis on many occasions. But it can also be a double-edged sword in the realm of sibilance, which the valley between 3 and 4kHz is intended to compensate for. Although the RA15s also have excitation in this range, they seem a little more blended overall, keeping a little more balance with the other elements. In this way, the QuietSea's feel a little more vivid, but also more punchy.
The QuietSea's treble is not as quiet as the model name suggests. The high end is thin, slim, somewhat sharp, energetic and crisp. The RA15s' treble is somewhat rounder and not as thin, subtly softer and more relaxed, without being muffled. Very good extension in the NF Audio.
The analytical and informative capabilities of the QuietSea are superior to the RA15s, the micro detail is also more visible. There is slightly more transparency and clarity in the QuietSea, while the RA15s' soundstage seems wider and deeper, not as rounded as in the Rose. The RA15s seem more relaxed and musical, giving a sense of greater density and body, as opposed to the cooler precision of the Rose.



Conclusion

The barrier of neutrality can be difficult to find. There are several brands that I have been able to test that are on that complex path, with little margin for error, where any deviation from the ideal reference curve can be detrimental. I think NF Audio is on that path and demonstrates it with the RA15s. In addition, it adds a pair of tuning filters to offer two shortcuts to that reference point that has not yet been found in the range.
The NF Audio RA15s are perfectly constructed dynamic IEMS, very robust, ergonomic and very compact in size. The brand continues to offer its classic packaging and accessories, in a persistent exercise in change. With a splashy V-sound, excited towards clarity and liveliness, the RA15s enjoy a very well-grounded bass. The midranges are a bit of a struggle to find that desired neutrality between two waters, while the highs find a remarkable balance in the mix. With a more than good sense of stage and separation, the RA15s are IEMS that move away from the dark path that has been trodden so often of late.



Sources Used During the Analysis

• EPZ TP50.
• Tempotec V3.
• Burson Audio Playmate 2.
• Aune X8 XVIII Magic DAC + EarMen ST-Amp.
• Aune M1p.

Purchase Link



You can read the full review in Spanish here

​

>>I am brazilian and I speak portuguese, so forgive my english, I’ll use translation tools to help<<


INTRO:

NF ACOUSTICS RA15 Review

DISCLAIMER: The NF Acoustics RA15 was sent to us free of charge by the NF Acoustics team for review. We are truly honoured and excited that this is our first collaboration with NF Acoustics. We humbly thank the kind peeps at NF Acoustics for their support.

Introduction: -

Today at Aural Cafe we will be reviewing NF Acoustics' newest budget offering RA15 from their “MUSIC SERIES”.

Before we start with our review of RA15 we at Aural Cafe would like to first apprise our fellow audiophiles with the brand NF Acoustics. NF Acoustics formerly known as NF Audio is a premium audio brand of Shenzhen Ningfan Acoustics Co Ltd which was founded way back in 2014 in Shenzhen China. NF Acoustics team from the very first day interestingly identifies themselves as In Ear ‘Artists’ and considers In-Ear monitors as a bridge between the music and the people. Since its birth, NF Acoustics engineers have been actively involved with professional musicians, vocalists, and music producers to gain a better understanding of the whole art of composing and recording and come up with solid offerings across different price ranges. NF Acoustics when it was founded in 2014 has taken a keen interest in the live performance market which clearly shows their love for music and musicians. Instead of following the more conventional route of coming up with a universal IEM the NF Acoustics team started their journey with the release of the customized NF3/NF3 bass in 2015 which became an instant hit in China. Moving on to 2016 NF Acoustics engineers released a proprietary ultra-high-frequency composite BA (Balanced Armature) unit. 2017 marks NF Acoustics' entry into Hongkong, Japan and Taiwan with the launch of a universal version of NF3 IEMs and 2018 is the year when NF Acoustics launched the world’s first Sonion EST-based IEMs JD24 and moving on to 2021 NF Acoustics came with an innovative Hi-Fi NE4 Evolution which featured replaceable face panels which changes the frequency crossover with the drivers and thereby affecting the sound tuning accordingly.

In fact, it was a special time for us at Aural Cafe as we were amazed by NE4 Evolution's innovative replaceable face panels. We still remember surfing through the NF Acoustics website to just understand the tech behind NE4 and then were pleasantly surprised to see the focus, and research that goes behind every universal and customized IEMs of the NF Acoustics. It was then we had a dream to own an NF Acoustics IEM as we were really impressed by the love that the NF Acoustics team had for hi-fi music and thought that we would surely own an NF Acoustics IEM someday through this review we are living our dream. Now coming finally to 2024, the year which marks a new dawn in NF Acoustics history as it transforms from NF Audio to NF Acoustics. We at Aural Cafe believe that the transformation is not just in brand name but there is a complete business revamp where we feel NF Audio will focus equally on universal IEMs so that not only professional musicians and live performers enjoy NF Acoustics items, but Audiophiles also be able to enjoy the hi-fi music the NF Acoustics way. Not only that we also believe that NF Acoustics from now on will also focus more on geographies such as Germany, the USA and India as well.

NF Acoustics RA15 is NF Acoustics' newest budget offering from their “MUSIC SERIES” which features NF Acoustics proprietary MC2L-10M dynamic driver in a replaceable sound tube setup. NF Acoustics proprietary MC2L-10M dynamic driver not only uses a high precision integrated tuning PCB board for better timbre but also comes integrated two high-performance Neodymium-Iron-Boron (NIB) magnets in a dual cavity design setup to provide more than 1 Tesla of Magnetic flux to achieve better dynamics and transient experience. When it comes to diaphragm material RA15 MC2L-10M dynamic driver adopts a medium rigidity and good elasticity 5U high polymer composite diaphragm to achieve minimum distortion and high dynamics. We at Aural Cafe also believe that RA15 gets its name from 10 mm composite diaphragm dd and 5U high polymer diaphragm material and RA stands for Reference Acoustics tuning. The story behind RA15 tech doesn't end here as it also features a replaceable sound tube setup. As per NF Acoustics what makes the RA15 replaceable sound tube technology different from the other brands is that their technical team not only focussed on the damping material but after extensive subjective listening adopted ‘Brass’ and ‘Stainless Steel’ metal for fabricating sound tubes. The brass sound tube makes RA15 lean towards warm musical tonality whereas the stainless-steel sound tube makes RA15 lean towards bright neutral sound tonality. The replaceable sound tube design setup thereby aims at serving to wide number of audiophiles which either like warm musical sound tonality or bright neutral tonality.

The RA15 retails for 89 US$.



Specifications: -

• Driver Configuration: Single 10mm Dual-Cavity Dynamic Driver
• Impedance: 32Ω ± 5%
• Freq Response: 20Hz-20Khz
• Sensitivity: 108 dB/mW @1 kHz
• Distortion: <1%
• Sound Isolation: 25 dB
• Cable: 0.78mm 2-pin 5N OFC with 3.5mm connector

Unboxing Experience, Design & Build: -

As you can perceive from our unboxing video ( https://www.youtube.com/shorts/36sBIkSL4Lc ) the NF Acoustics RA15 arrives in a compact square-shaped black box. The NF Acoustics team's decision to go with a combination of black and fluorescent orange shades for designing the RA15 box comes out very attractive and surely going to appeal to the young audiophiles as well as the professional gamers out there. The front side of the box is mostly dominated by a snap of RA15 IEMs along with the NF Acoustics brand logo placed at the right corner of the box while the RA15 specifications are inscribed on the back side of the box in white colour fonts. On pulling out the internal box we were pleasantly surprised by the record-style packaging taking us back to the good old vinyl days. The top layer of the box showcases RA15 IEMs’ shells being placed in a cool vinyl-style cutout. The RA15 features all-metal casted shells with a tapered faceplate in metallic charcoal grey colour. The shells are a bit heavy in comparison to more conventional resin-based IEMs but the team at NF Acoustics have smartly tried to overcome it by applying their years of experience in manufacturing customized IEMs to achieve a compact ergonomic shell for RA15. One can also spot two vents on each shell of RA15 which will surely help a lot in reducing air pressure and increased dynamics. The RA15 shells come with a QDC 2-pin design which we believe was selected by the NF Audio team to further reduce the pressure of wearing while listening to music. Like NF Acoustics we at Aural Cafe also give high importance to wearing comfort and fit and we can say that we are happy with the overall ergonomic design of the RA15 shells as it not only helps with the comfort quotient but also provides decent passive isolation while listening to music while commuting. On taking off the vinyl cutout one can come across cables and other accessories RA15 comes teamed with being placed at the lower layer of the box. NF Acoustics RA15 Comes with a lightweight high quality 1.3-meter silver-plated 5N oxygen-free copper cable with a 3.5 mm earphone connector. The provided lightweight flexible cable just adds to the comfort of listening to music on the go. When it comes to ear tips RA15 comes with NF Acoustics MS42 high-quality silicone ear tips in four XS. S, M, and L sizes. As NF Audio RA15 features a replaceable sound tube setup it comes with one set of the brass sound tube being placed along with the accessories while the stainless-steel sound tube comes fitted with the RA15 IEMs’ shells straight out of the box. The RA15 also comes with a small white colour leather storage pouch which ends up adding a hint of elegance to the RA15 set of accessories. We at Aural Cafe considering the price are quite satisfied with the minimalistic design and quality of the shells, cables and sensible set of accessories.






Sound Analysis: -

We would like to state here that the sound impressions are based on our usage of NF Acoustics RA15 with stock tips and cables. The effect of other branded ear tips and cables on sound impressions has been dealt with separately in the Synergy section so we would request every audiophile to go through that section for sure.


Credits: @hiendportable

• Tonality: - After listening to different genres of music on RA15 with many sources for several hours we at Aural Cafe can confidentially state that the RA 15 flaunts a neutral to slightly bright and clean sound. The brass sound tubes definitely have better and smoother tonal balance across the frequency in comparison to the stainless-steel sound tubes. Although the sound tubes don’t have a sizeable effect on the overall tonality and the overall sound remains transparent and clean both on brass and stainless-steel sound tubes it’s the brass sound tubes that add the soul to the instrument's timbre and the vocals texture. Since the RA15 exhibits a smooth tonal balance with the brass sound tubes we can recommend it for the sound designers who are sitting on a tight budget. We especially loved listening to slowcore, indie rock and vocal-centric soundtracks such as “Apocalypse” by cigarettes after sex on RA15.

• Lows: - The lows on RA15 are tuned using dual magnetic circuit systems which end up providing more than 1 Tesla of magnetic flux. When we started listening to music on RA15 right out of the box we felt that the lows on RA15 were just average at best but after the burning period, the lows surprisingly improved for the good. There is a negligible effect of sound tubes on the bass, but the brass sound tubes do add a bit more warmth to the overall lows. The midbass in terms of quantity and quality just hits the nail on the head. The dual magnetic circuit adds superb speed to the tight midbass which makes the whole listening experience quite fun and foot-tapping. The overall dynamics and transient response are surprisingly good on RA15 considering the price. We loved listening to ‘Bad Guy’ by Billie Eilish and ‘Vadiya’ by Amit Trivedi on RA15. Now coming on to Sub bass, the Sub bass on RA15 is just average at best. The Subbass lacks both in terms of quantity and quality. We definitely missed the rumble and sub-bass layering and decay while listening to different soundtracks. We would also like to add here that the bass is tuned quite precisely without adding any muddiness to the mid-frequency.

• Mids: - We at Aural Cafe feel that the NF Acoustic team have tuned the mids on RA15 very tastefully. When it comes to positioning the mids on RA15 is a tinge more forward and immerse smoothly with the lows and high frequency. When it comes to the effect of the sound tubes on mids we felt that the stainless-steel sound tube does make the upper mids a bit more exciting but it’s the brass tube that takes the lead as it adds the soul and lovely texture to the vocals in the mids along with a smoother upper mids suitable for long listening hours. The lower mids are not the best we have heard whereas the upper mids are smooth and decently open and airy with the brass tubes but become a bit shouty with stainless steel tubes. Both the Male and Female vocals are absolutely outstanding taking the price into consideration. The male and female vocals on RA15 sound authoritatively clean without compromising on texture and feel while listening to complex rock numbers. The integrated tuning PCB board also plays its role amazingly well to add soul and life to the timbre and tonality of the instruments. While the micro details retrieval capability of RA15 is above average we at Aural Cafe would love a touch better layering. Since the vocals on RA15 with brass tubes on are outstanding we at Aural Cafe loved listening to vocals-centric soundtracks such as ‘Out of Time’ by the Weekend and ‘Scar Tissue’ by Red-Hot-Chilli-Peppers.

• Highs: - The Highs on RA15 are clean, smooth and airy with brass tubes but become quite shouty with the stainless-steel tubes and thus not suitable for long listening hours. The micro details are not on the face but come in a much more organic way while listening to different genres of music. While the lower treble is smooth and clean the upper treble lacks extension. Taking the price of 89 USD into consideration we are overall satisfied with the smooth and airy treble keeping in mind the overall neutral tonality of the RA15. We at Aural Cafe would like to suggest using brass sound tubes over the stainless-steel tubes as highs are smoother and thereby suitable for longer listening hours. We loved listening to ‘Stairway to Heaven’ by Led Zeppelin, ‘Paayalliya’ composed by Amit Trivedi for the movie Dev D and sung by Shruti Pathak and enjoyed the high notes listening to ‘Ae Watan’ sung by Arijit Singh for the movie Raazi.

• Soundstage & Imaging: - The soundstage on RA15 has a beautiful immersive feeling which makes the whole listening session quite enjoyable. The soundstage width takes lead over depth which is just average at best. The separation between the instruments is above average which makes listening to “Hotel California” by the Eagles quite enjoyable. We also loved the shimmer coming out of different instruments while listening to ‘Zariya’ composed by AR Rahman for Coke Studio India. While the micro detail retrieval ability, speed and transient response are outstanding on RA15 the layering is just average at best. When it comes to imaging the imaging on RA15 is just decent but nothing exceptional to say.

• Synergy: - We here would like to state that we at Aural Cafe do believe in burn-in when it comes to DD-based IEMs and would suggest at least 20 hours of burn-in period to get the best out of RA15. When it comes to drivability, we are happy to communicate that RA15 is easy to drive but would definitely suggest using it with a hi-fi source to get the best out of RA15. Although RA15 is just an 89 USD IEM we tried it with numerous sources, cables and tips to see how it affects the sound quality for fun. We tried it with several cables from Linum, PW Audio, Rhapsodio, Modular Workshop and Linksmith cables and felt that RA15 Synergise really well with Linum SuperBax cable which adds a bit more soundstage width to the RA15. When it comes to ear tips we felt that RA15 goes decently well with the stock narrow bore ear tips but it really shines well with Divinus Velvet Silicone ear tips which adds a touch more depth and body to the lows. When it comes to sources we tested RA15 with a line of dongles such as iFi Audio GO Link, Go Bar Kensei, Aune Yuki, and Tanchjim Space and felt that RA15 sounded best with Aune Yuki and iFi Go Bar Kensei. We also tried RA15 with a number of portable daps and desktop sources from our source banks such as Astell and Kern SP1000M, Dethonray Prelude DTR1, DTR1+, DTR 1+ LE, Listening M1, SG1 Gold Bluetooth USB DAC/Amp , Aune M1p and felt that it goes really well with Dethonray SG1 Gold and Aune M1p as it adds a bit of warmth and rumbles to the lows whereas the new Dethonray Listening M1 and Dethonray Dtr1+ LE improved the layering and soundstage depth and make us feel that we are listening to more expensive IEMs. Overall we would suggest a source with a black background and neutral tonality, a high-quality SPC cable and narrow bore ear tips as it goes well with RA15.

Conclusion: -

We feel that the NF Acoustics team through RA15 have tried to showcase their take on neutral IEMs at affordable prices. From the outside RA15 just looks like just another IEM in the ocean of budget items but it’s the dual magnetic circuit and dual cavity design which does add amazing speed and transient performance to the Lows. The male and female vocals sound clean on RA15 along with lifelike texture. We also like to add here that the NF Acoustics team have done a great job in adding a soulful timbre to the musical instruments, but we would definitely love a lot more sub-bass in terms of both quantity and quality in the Lows. When it comes to the replaceable sound tube design, we felt that RA15 shines its best and is soulful with the brass sound tube as the stainless-steel sound tube makes the upper mids a bit shouty. We at Aural Cafe would like to conclude this review by saying that RA15 is definitely not for the bass heads but if you are an audiophile who loves neutrally tuned IEMs RA15 can be a good choice as it is not only a neutral IEM but RA15’s midbass speed and top-notch vocals which do make it different from the other IEMs in the less than 100 USD range and make the listening sessions quite fun and foot tapping.

Non-Affiliated Link: -

• https://hifigo.com/products/nf-audio-ra15
• https://www.amazon.com/HiFiGo-Cloud-Diaphragm-Air-Assisted-Circulation/dp/B0D6GMFP1L?th=1

General/Build/Packaging/Comfort
NF Audio is a brand that caters mostly to pro musicians in Mainland China as well as outside of China, they offer both stage use IEMs as well as IEMs for audiophiles, but the main focus is still on pro musicians based on the offerings. They are slowly venturing into the audiophile’s market, offering IEMs with tunings suitable to most audiophiles. I have the RA15 with me today, it is touted as a musical’s series from NF Audio. It is a single dynamic driver with full metal shell, and comes with an interchangeable nozzle which alters the sound signature based on the nozzle installed.
Packaging is very nice and the unboxing experience is very positive and premium looking in my opinion. It comes with the MS42 eartips from NF Audio, purely nitpicking, I do wish it has the option to go for 4.4 or 3.5mm termination.
In terms of build quality, it is very solid and the overall unit is not heavy nor protruding edges which might cause discomfort.



Gears used for this review

• Aune S9C
• Macbook Air M2 3.5 Out
• NF Audio RA15 with stock cable and stock eartips (Gold Nozzle)

Foreword
My review is solely based on what I hear via my equipment and I never consider my reviews to be objective in any way rather a subjective approach. Do take into consideration that everyone’s ear anatomy is not the same, so the psychoacoustics perception might be different as well, but i believe it will not stray too far

Sound Impression ( Gold Nozzle )
The RA15’s tuning is leaning towards V shaped and it has plenty of energy on the top end. Timbre sounds very natural to my ears and it has quite a good body to it overall with sufficient note weight to it. I have nothing against V shaped tuning, personally i think in order to enjoy music, there has to be some sort of colorization to it, but that is just me and my
opinion and i do not represent the majority of the audiophiles out there. Timbre sounds fairly natural to my ears



Bass

• Bass on the RA15 is not lacking by all means, It is punchy has good quality bass with sufficient quantity, but certainly not a set where i would recommend to basshead
• It has good textures and body to it, doesn’t sound loose and thin
• Mid bass has good slam and punch to it, listening to Metallica’s Lux Aeterna is very pleasing as every hit on the drum be can felt
• Sub bass rumble is there when the track calls for it, doesn’t really extend that deep, it is evident in Hans Zimmer’s Why So Serious, slightly lacking the rumble
• The speed is also excellent on the RA15, handling complex tracks with ease without sounding muddy and bleeding into the mids

Mids

• The midrange is good with sufficient note weight, not sounding too thin and vocal positioning is not too forward nor laid back
• Female vocal has good energy to it and good texture
• Male vocal that has low baritone voice such as Zhao Peng retains the warmth and texture to it, it doesn’t sound thin at all, very pleasant experience
• The upper mids are not shouty at all and it does very well in terms of giving the female vocal a slight boost
• Slightly recessed in the mids, but not really a deal breaker

Treble

• Treble response on the RA15 is energetic but not harsh nor sibilant
• On the stock silver nozzle, the treble can be too much to handle for those who are sensitive to treble
• Good amount of air and presence and contributed to good sense of staging and imaging as well
• Detail retrieval is good and i can hear the nuances distinctively without having to try hard, an example of such track is Faye Wang’s 旋木，the finger slides from the guitar can be heard easily

Soundstage/Imaging

• Soundstage for RA15 is good for the price, having a good sense of width, depth, a little lacking in height but very good overall. It is quite spacious sounding, listening to orchestral or live tracks is very enjoyable on the RA15
• Imaging is also a strong point for RA15 as well, instruments can be pinpointed easily even on complex tracks such as Slipknot’s People = crap!, well layered and good separation

Driveability

• RA15 is not hard to drive, give it something like Apple’s Dongle is actually sufficient to get good sound and listening volume out of it
• It scale very well with source but not so much on the amplification

Sound Impression on Silver Nozzle

• From the bass response to the mids, it is more or less similar sounding to my ears
• Vocal positioning however is more forward compared to red ring nozzle
• Female vocal is even more lively compared to red ring nozzle, this is due to an early rise on the upper mids, i find the female vocal to be very enjoyable on this nozzle, but i can’t say the same for those who are sensitive with the upper mids boost, do take into consideration that your experience might vary
• Soundstage is slightly smaller on this nozzle, but imaging capability is excellent
• The treble is also being boosted to give more resolution and better perceived detail retrieval capability
• I would say this is a more of an analytical kind of tuning compared to the gold nozzle which is slightly tame on the top end with slightly thicker note weight

Comparison (Simgot EA500LM Gold Nozzle)

• The tuning of Simgot’s EA500LM is more on the harmanish side, overall note weight i would say they are more or less quite similar
• Soundstage is just slightly out of your head compared to RA15 which has a wider and bigger perception of stage, imaging is more or less similar
• Mids are forward on the EA500LM and the upper mids might be perceived as slightly offensive for those who are sensitive in this region
• Mid bass on the EA500LM is not as punchy, sub bass does have a slightly better extension compared to RA15
• Treble is slightly smoother on the EA500LM
• The EA500LM is easy to drive and scales with better source, similar to RA15, but doesn’t benefit much from amplification based on my listening impression

Final Thoughts
I have a very positive experience with the RA15 and I definitely look forward to trying out their upcoming products when I have the chance. RA15 is a solid product overall that offers versatility with the swappable nozzle, although this is nothing new in the industry, but it does offer the user to switch to different kinds of tuning whenever they feel like it. With all things considered, this is not to say that RA15 is perfect and without flaws, or perhaps i shouldn’t say flaws because i’d be instilling my own preferences instead of properly reviewing the IEM itself, i would say if the sub bass quantity is slightly boosted while retaining the same quality and control over it, it would make the overall listening experience more “musical”, also a slightly tame treble on both nozzle would make the overall note weight sound thicker. All in all, the RA15 is paving the path for NF Audio and personally I think they are on the right track. The RA15 gets a recommendation from me if you are not that sensitive to the treble region.

*RA15 is being sent over for the purpose of this review. I thank NF Audio for the opportunity. I am not influenced in any way to produce this review nor do I receive any monetary compensation.

Head over to the following link if you are interested in getting a pair!
NF Audio RA15- Non affiliated

Disclaimer
Please note that I am not an audiophile, and this review does not delve into the technical aspects of the IEMs. My impressions are based on my personal preferences, and others may have different experiences with this product. I also have a very limited experience with audio products so please take this review with a grain of salt.

The NF Audio RA15 was lent to me by @mars chan because I was in the market for headphones under 100USD that could be used for casual gaming and music listening, it's not a part of any tour.

Price: 89 USD
Link: https://hifigo.com/products/nf-audio-ra15 (not affiliate)


Part 1: General Product Details

Package Inclusions:

• IEM shells & cable
• Carry pouch
• 4 pairs of MS42 Eartips
• Tuning Nozzles

The IEM Shells
- The shells are greenish-grey teardrop shaped cnc-ed aluminum with the NF Audio logo printed in light brown on the faceplate.
- Weighing in at 9.4g, these are the heaviest IEMs I’ve tried, and the MP143 Salt pales in comparison at 7.8g. It’s a little fatiguing to use for more than a few hours for me due to the weight but over time, I got used to it and was able to wear this pair without any problems.




The Carrying Case
- The pouch is a plain white drawstring piece with black cord. Nothing special about it

The Cable

• The cable is of a pearlescent white color. It’s very thin and feels like it can easily be damaged. despite that, it’s very well behaved and easy to wind or position.
• The silver chin clutch and black splitter are both made of plastic.

Part 2: Subjective review


General Usage Impressions

• The shell is a little slippery due to the shape and material. You need to be very careful when handling these
• Despite being heavier than the Hidizs MP143 Salt at 9.4g, I didn't have trouble getting used to the weight. Maybe because the center of gravity was inside my ear instead of outside.
• The shells are small, and are able to give me a good seal. This set made me realize that my right earhole needs one size smaller eartips than my left earhole.
• You won’t have trouble with fitting the shells to the cable, there’s a jacket over the 2 pins that will only fit on the correct pair so it’s much easier to fit the two sides together!

Sound Impressions

• Gold Nozzle
  • The treble is less pronounced, so it’s just warm. I guess this nozzle is supposed to be the “balanced” one.
• Silver Nozzle
  • The treble is more pronounced, more bright. Some songs are are a bit more sibilant to me.
  • I don’t like using this as it seems exhausting to me.
• The soundstage is average at best, it’s not as wide as I hoped, but it’s good nonetheless.
• I used this set for gaming competitively (Overwatch 2) and it was able to give me good information on where certain enemies are, details were great.

Final Thoughts
Premium build quality, outstanding details, with some excellent accessories I think it’s a no brainer that the NF Audio RA15 is a great buy for its price. I have yet to try out any IEMs in the same price bracket that can give the same performance as these (See my profile for what I've reviewed, there's just a few of them. ).

Introduction​

The NF Audio RA15 represents an affordable, highly-capable in-ear monitor that has been designed to appeal to audiophiles on a budget. For an asking price of $90 or so, the RA15 easily stands out with its unique dual-sound tube design, thanks to which users can tailor the sound signature according to preference. With a robust build, these IEMs are equipped with a dynamic driver featuring a high polymer composite diaphragm and a dual-magnet circuit, offering enhanced sensitivity and a more significant driving force. Whether you're a casual listener or a more discerning audiophile, the RA15 promises to deliver a detailed and immersive audio experience. In this review, we will go through different aspects of the RA15, ranging from its build quality and design to fit and comfort, and sound performance at varied frequencies, including its suitability for gaming.

Context​

I have been using the RA15 for some weeks. I loved this pair of sets so much. I use it with my Xduoo xd 05 basic (with NE5532 OP-Amp),ddHiFi tc44c, and LG V60. Also tested it with Fosi Audio DS1 for its sound stage performance. I use the stock cable also an upgraded cable. But I have changed the stock tips. Try it with different eartips like Spinfit W1, 145, CP100+, Penon Orange, Velvet, and TRI clarion eartips. My pick for this iem is Penon Orange eartips. They provide a good seal for my ear and provide a good sound for my preference.

Note: I use these iems with this cable, eartips, and sources. That is the basis for my overall review.

Disclaimer​

I received this IEM from "NF Acous宁梵声学" for review needs. And each corporation has no direction on what to write and what not. With the sound I listened to, the whole evaluation represents my objective experience and honest assessment.

one more item. The review is grounded in my own experience and what I learned from many IEMs. Your experience could change depending on personal taste and anatomical variations including ear canal depth and form. Also for some sources like DAC, eartips, cables.

Unaffiliate links​

If you want to buy this iem, visit SHENZHENAUDIO, or AliExpress's official store NF Acous.

Gears Used​

• ddHiFi tc44c (for Bass details)
• Fosi Audio DS1 (for Sound stage)
• LG V60 (for phone sound test)
• Xduoo XD05 Basic with N5532 op amp (overall sound

Technical Specification

• Driver configuration: Double Cavity Dynamic Driver
• Frequency response: 10 Hz - 40000 Hz
• Impedance: 32 Ω
• Sensitivity: 108 dB/mW
• Cable: 2-pin 0.78mm 5N OFC cable.

What in the Box

• - Iem
• - 4 pairs of MS42 silicone tips (XS, S, M, L)
• - cable
• - carrying pouch
• - 2 pairs of tuning nozzles

Build Quality​

NF Audio RA15, against expectations, proves to have an almost perfect construction for its class. The IEMs sport an all-metal build along with a dual-cavity design to make them tough and long-lasting. The use of metal shells not only gives the IEM a higher quality feeling but also protects the internal parts from any serious impact, including the dynamic driver. Also, the removable nozzles make the model versatile for easy maintenance or upgrades. There is also a silver-plated copper cable included, adding to its high-quality make for being flexible and tangle-free. While the build is robust, the fit is not quite ideal for everyone, especially for those with smaller ears.

Design​

The NF Audio RA15 is both practically and aesthetically pleasing in design. The IEMs sport an all-metal body that houses a sleek, nice feel from outside, much like the premium build these advertise. The RA15 uses a dynamic driver inside with a high-polymer composite diaphragm and a dual-magnet circuit that greatly improves responsiveness and accuracy on the IEMs. Indeed, with two interchangeable sound tubes included-one for a warmer signature and another for a brighter, more treble-focused response-it does grant options for customizable listening. It is definitely that one design feature alone that makes the RA15 highly desirable for those people who do appreciate versatility in their audio gear.

Fit and Comfort​

Fit and Comfort: Generally, the NF Audio RA15 can be comfortable but might not fit each and every different anatomy. The monitors are delivered with several eartip sizes so that one can catch the best seal for quality sound. Some users may find that the metal housing sticks out slightly, requiring occasional adjustments to maintain a secure fit. Still, with the ergonomic design and relatively light build, the RA15 is comfortable enough to be worn for long listening sessions. As mentioned earlier, most users should find it snug, but particularly small ears may need one to look at other options.

Internals/Tuning Nozzles​

One of the interesting design features in NF Audio RA15 is that it bears a dual-sound tube design. it allows users to change the sound signature by switching different tuning nozzles. To this end, NF Audio RA15 comes with two interchangeable sound tubes, with one aimed at a warmer sound profile and another for a brighter sound, treble-heavy. This system with two sound tubes serves effectively to alter the tuning of IEMs, enabling the user to tailor their own listening experience. Inside, the RA15 boasts a dynamic driver with a high-polymer composite diaphragm and dual-magnet circuitry for greater sensitivity and responsiveness to the IEMs for a sound that will prove detailed and dynamic. Adding the facility to switch between different sound tubes-which is seldom found in this price category-the RA15 definitely is one of the more attractive models for persons who especially like fine-tuning their audio.

Sound Impression​

The NF Audio RA15 sounds really good, considering the price one pays for these IEMs. Overall, the RA15 has a well-detailed and well-balanced sound signature across the frequency spectrum. The bass, while impactful and controlled, is only enhanced by the warm sound tube attached; the midrange is clear and slightly forward, and the treble is crisp but not overly bright. Switching over to the bright sound tube indeed shifts the emphasis more towards the upper mids and treble, providing an even more analytical listen with greater retrieval of detail, although it does end up being fatiguing with longer listens. Overall, the RA15 offers a pretty versatile sound profile that can meet a variety of listening preferences.

Sub-Bass​

Sub-bass is present in the NF Audio RA15. However, it never becomes over-emphasized. Additionally combined with the warm sound tube, the sub-bass supports the rest of the frequency range very well without shadowing the rest. This sub-bass is somewhat lacking in depth and rumble to the users who hear this from more bass tuned IEMs. The emphasis here is on clean and tight bass response, more about precision than power. This makes the RA15 suitable for genres that demand a controlled low-end rather than a booming bass.

Mid-Bass​

Mid-bass is more forward on the NF Audio RA15. It can give this IEM with a tube-oriented warm sound a really punchy and satisfying bass, which fills the bottom end quite pleasantly. The mid-bass is tight and really well defined, avoiding any kind of muddiness that would affect some budget IEMs. This no doubt makes the RA15 an excellent choice for those who enjoy genres like rock, pop, and electronic music-with genres in which mid-bass is absolutely indispensable. It requires this bright sound tube to relegate the mid-bass and move both the mid and high into the spotlight.

Male Vocal​

Vocals on the NF Audio RA15 are clear, natural, and well-articulated. Male vocals are slightly forward, and tonality is on point; it's hard not to take notice with most tracks. Deep baritone or higher-pitched tenor, male vocals are done right on the RA15 for a smooth and involving presentation. The warmth brought on by the mid-bass works great with male vocals, making them sound rich and deep but without taking anything away from the rest of the presentation. The male vocals keep their clarity but lose some warmth, coming more forward in the mix while using the Brilliant Sound tube.

Female Vocal​

The female vocals on the NF Audio RA15 shine just as easily, with a focus on clarity and detail. Tuned-in in the upper midrange, this yields females that shine bright, yet airy, accented with delivering every nuance of each performance. RA15 manages to retain control over the sibilance in a bright sound tube, which makes it a very recommendable choice for people listening to vocal-centric music. The soft female vocals are given a little warmth by the warm-sounding tube, which makes them sound fuller yet more intimate at the same time. In general, RA15 gives out a good and balanced type of vocal.

Treble​

The performance of the treble is different on the NF Audio RA15, depending on which sound tube is in use. With the warm sound tube, the treble is crisp and detailed, providing enough sparkle to keep the music lively without getting harsh or fatiguing. This makes the RA15 suitable for long listens. In contrast, the bright sound tube emphasizes the treble energy, which makes it more easy to feel and gives very well-delivered high-frequency extension. This may contribute toward a good sense of detail and airiness but will come at the cost of some potential listener fatigue, especially where the use is for longer periods. The choice of tube promises to offer the best treble response for one's personal taste.

Instruments​

Some of the great features of NF Audio RA15 are instrument separation and clarity. The IEMs really manage one separate instrument in a track very well without allowing it to bleed in with all the rest, which in turn allows each to be distinctly heard. It is kind of a detail impressive for an IEM in that range. Whether one is playing complex orchestral pieces or more straightforward rock tracks, the RA15 presents each instrument as clearly defined and placed within the soundstage. The sound tube produces a sound that is warm but full-bodied and rich in tone; however, the bright sound tube underlines detail and separation even more.

Soundstage​

The soundstage in the NF Audio RA15 is reasonably wide for its price point-an expansive soundstage quite hard to grasp within an IEM at this price. Said expansiveness isn't so deep, but the width is there and is one that would afford an immersive listening experience. Imaging is precise with instrument and vocal positions well placed in the stereo field. This makes the RA15 a great choice for those who appreciate a well-organized and spacious soundstage for either music listening or gaming. The soundstage on the RA15 is not as wide as some higher models but very impressive for the price.

Gaming Performance​

So, the NF Audio RA15 is quite a decent performer, mainly considering its price range, for gaming. Here it goes against some other popular games:

CS: GO: With the RA15, sitting at the perfect midrange neither too forward nor recessed led to a minute resolution in imaging, thereby making players precise in sensually locating the origin of those sound cues in competitive play. The soundstage, although not the widest, offers enough spatial awareness to detect an enemy's movement and position with ease. This ever-so-slightly forward midrange ensures that critical audio cues, like the Pitter Patter of enemy footsteps or the clinking of nades, are easily identifiable, giving the player an edge in tight matchups.

Valorant: Just like in CS: GO, at Valorant, RA15 sounds pretty good, where good positional audio gives a competitive advantage. The evident mids and controlled bass on the RA15 help to quickly differentiate between sound cues, like gunshots, footsteps, or ability sounds, to not get lost between them. Coupling with the soundstage, the distance and direction from which the enemies were would be noticed to help in strategic playing as well.

Battlefield 2042: Battlefield has always been about large-scale maps and massive firefights. The RA15 does well in this aspect, helping to transport players to the battlefield with its wide soundstage and detail in sound. Explosions, shooting, and ambient noise do good reproduction, though the RA15 is lacking a little in sub-bass, especially deep sub-bass, which tends to capture the intensity of some of the larger explosions. Still, the clarity in mids and highs lets clear communication and detection of enemies in big, open maps.

Warzone 2.0: It's a good performer in Warzone, where the constant good spatial awareness is the difference between winning and losing. With its wide soundstage, it becomes pretty easy to pick out the distant gunfire and oncoming enemies in the mix while having detailed mids to make sure footsteps are never missed. However, lovers of heavy bass might find that in extra heated firefights, the RA15 gets a bit too talkative in the sub-bass regions.

Rainbow Six Siege: In a game like Rainbow Six Siege where count of every possible sound is crucial, the RA15 shines bright. In this game, the IEMs really show their accurate imaging and separation properties by making it easy to distinguish between various environmental noise and opponent movements. The sound signature of the RA15, especially with the bright sound tube, highlights the highs and mids of a track, which helps to catch subtle audio cues such as reloads and movement on different surfaces.

Conclusion: NF Audio RA15 presents a fun balance and has enough details, making it definitely fit both casual or competitive gamers. It won't have that thumping in the lows that is of preferred signature among many gamers; however, it has plenty of clarity and imaging for on-point in-game awareness.

Overall Ratings​

Note: This rating is based on my listening experience.

Conclusion​

The NF Audio RA15 has been absolutely excellent value for money and all-rounder so far. Solid build with unique dual-sound tube design, it allows tuning one's presentation in style, simply like having two different tunings within a single IEM. Clear, highly detailed sound is presented in all the music genres and gaming frequency ranges. While certainly not the endgame for any basshead out there looking for deep resonant lows, it makes up for this with very good midrange clarity, treble detail, and instrument separation. Its appeal widens with its performance in gaming, especially for competitive shooters. For someone looking for a wallet-friendly IEM that does not compromise quality and versatility, the NF Audio RA15 would be a strong contender.



Thanks for joining me on this deep dive into the NF Audio RA15! I hope this review helped you decide if these versatile IEMs are a good fit for your listening preferences. Happy listening!

★ Introduction :-

NF Audio is a well-known chifi brand but they lag behind other chifi manufacturers. They mainly make in-ear monitors (IEM). I haven't used much of their offerings. Although I purchased their NM2 a few years ago for personal use and found it to be a pretty ideal set sound wise.Their target includes both single dd as well as multi-driver IEMs, with a reputation for descent build quality and sound performance even with the attention to detail they always have in the user experience. I recently got my hands on their music series RA15 model single dd IEM, Which is my second used item of NF Audio so far. I've been using this IEM regularly for a few week. Now, I'll try to highlight all aspects of this IEM in my review. So that it is convenient for you to understand how equitable it is for this price category.



★ Disclaimer :-

This review unit was sent to me directly from NF Audio. I had no financial agreement with them to promote their product. So, the entire opinion of this review is completely my personal.

★ Box Content at a Glance :-

The RA15 set provides the necessary accessories along with beautiful packaging. It comes with a single end stock cable, and a black color card bord with four pairs of different size silicon eartips. At the same time, a thin leather pouch is provided to carry the earphone. Besides, also two pairs of tuning nozzles are provided. One of which is gold and the other one is silver.




1. A pair of RA15 IEM ×1
2 . Four pairs of different size ms42 silicon eartips
3 . Two pairs of interchangeable nozzle
4 . silver plated copper cable ×1
5 . Simple leather pouch ×1
6 . User manual guide ×1

The quality of the provided accessories was not very satisfactory. Especially not to mention the stock cable, very average quality of plasticky material braided sliver plated copper cable which will definitely become useless after a few days of regular use. The carrying pouch was also very simple, which protects the IEM from scratches, but it does not seem to be effective in practical life. It's a bit disappointing to get such average accessories from an IEM for around $80. At this price, others in the market offer a better unboxing experience.

★ Specifications :-

★ Design, Build & Comfort :-

This IEM shaped like a small candy, the shell of this IEM is fully metal constructed, so it feels solid in hand and ensures robustness. But here the design is not very attractive because Nf audio has focused more on the build quality than the design here. Despite the metal alloy build, but also it has been reduced in size due to which it fits perfectly in the ear and when worn in the ear, it can be said that it is super comfortable. It can be used comfortably for long periods of time even for those who are used to using IEMs while lying down. I was able to wear it in my ears for about three hours straight any kind of issues without earache or loss of balance. It can fully satisfy those who want to avoid problems like fit issues or ear heaviness in daily commuting.

★ Sound Aspect :-

RA15 is basically a set of bright U shape profile, where the emphasis of treble is very high. As its internal configuration, the full sound frequency has been handled with a 10mm dynamic driver and two interchangeable nozzles provide a test of different sound tonality. Although the sound of the gold nozzle is fairly safe tuned, the silver nozzle produces a more detailed & analytical sound. Where the upper mids lose their control and make the lower treble aggressive, this tuning nozzle will undoubtedly be considered unusable.


Credit : Super* review

★ Gear used :-

1. Questyle Audio Engineering CMA Fifteen
2 . Cayin Ru7 (Se & Bal both)
3 . Questyle m15 (Se & Bal both)
4 . Quloos Mc01 (SE & Bal both)
5 . Epz Tp50 (Se & Bal both)
6 . Fosi Audio Ds1 (Se & Bal both)
7 . Fosi Audio Ds2 ~ 2024 (Se & Bal both)
8 . Blon V1 (Se & Bal both)

RA15 is a set of 32Ω impedance whose sensitivity level is 108dB so not very powerful amplification is needed to drive it, I got enough loudness from the phone's 3.5mm port, but if a good quality dac amp or portable player is used, then it gets scaled up with the source(warmish-slight neutral)and becomes better sounding. However, the best pairing I've found with CMA Fifteen. Better stage depth, dynamics, improved imaging even a bit better micro detailing capability.Tonal balancing is also a little bit better.



Now, I will discuss the sound in detail, I will start with the Low end of this set, i.e. the bass....

★ The Bass :-

In the context of the bass section, I will say that this set is generally mid bass focused. However, there was rumble of sub bass but it is relatively less.There wasn’t much deep or rumbly effect like typical harman tuned sets. Interestingly, they have limited the presence of sub bass to reduce bleed into the mids. Again, the mid bass punch is good but the bass notes lack proper weight and less depth. Some of these improvements can be observed in the silver nozzle.The attack & decay of the bass was fairly fast and at the same time the control level was good, but the physical authority that a well tuned dd bass usually has, which was noticeably lacking here. Additionally, the mid bass is limited to 200hz in order to maintain politeness in its control levels.

★ The Mids :-

This set has enough clarity in the upper mids and the presentation was also very forward. Generally, there was no tendency for too much shouty or overly dull, but there is some emphasis on high-pitched vocals. As a result of which the thickness of some female vocals body becomes lean even lifeless.This is most noticeable in the silver nozzle. On the other hand, the gold nozzle has a hint of warmth touch in the lower mids which gives some fullness to the male vocal but it does not ensure the authentic character of the vocal. Harman-ish or v shape tuning is always thinner i.e recessed to maintain sufficient clarity in lower mids otherwise the contrast between bass and treble region will not be maintained. So lush even melodic vocals cannot be expected from this type of tuning. As a mids lover I personally don't like harman target very much.

★ The Treble :-

The treble part of this set would be described as clean & moderately detailed. Upper treble extension was good but I noticed more treble harshness from the mid to lower treble which was quite tiring. At the apex of this area some unpleasant sibilance issues arise, like s,,,sh,,s,,h, which add harshness. This situation can be noticed more in the silver nozzle and even enhances the brightness of the treble and increases the details but it is not at a tolerable level. Moreover, the treble is not well-articulated, the actual character of other high frequency instruments like cymbals, hi-hats is slightly distorted.Then I notice that a kind of metallic shrillness appears in the treble region which makes the 8k area even more peaky which becomes unlistenable. Even though I'm fairly tolerant of treble energy, but its silver nozzle fatigued me by treble. Which was full of unnatural sparkle and dry timbre. That's why the less detailed sound was found on the gold nozzle, but it was quite safe & enjoyable. Unfortunately there was a touch of unrefined treble though.

★ Technicalities :-

The RA15 technically delivered a solid performance. But I would say silver nozzle's contribution deserves more prominence in this regard. The sound stage was wider with accurate depth & height. Imaging capability gave descent result in gold nozzle but got holographic imaging in silver. On the other hand, the presence of micro detail has also increased significantly. Along with this, the dynamics and micro dynamics punch was also on the good side so there is no room to complain much. but the tonality lacks enough authenticity even the silver nozzle will seems more dry. As a single dd set, the timbre was also surrounded by a metallic touch instead of being natural, which created a somewhat disappointing situation. Those who prioritize the natural tone & timbre of dd IEMs will surely be disappointed.



Overall rating out of 5 is what I would give

Bass : 4 /5
Mids : 3.8 /5
Treble : 3.8/5
Technicalities : 4.5/5
Dynamics & speed : 4/5
Build & Aesthetics : 4 /5

★ Comparison :-

~ NF Audio RA15 vs Artti R1 ~

Considering the current market, the R1 triple dd set is offering decent sound quality. But it doesn't have the modular tuning versatility like the RA15. The sub bass region of Artti R1 is quite strong compared to RA15, for punchy mid bass, RA15 will be one step ahead. So overall bass note weight wise R1 is in a better position, but fast attack & decay RA15's strength. Although both IEMs are not very strong in the mids section, I personally prefer R1's midrange because it has enough detail in the upper mids which is not harsh sounding like RA15's silver nozzle. In its gold nozzle, although the vocal section is fairly safe, there is a tendency to make the female vocal shouty, which is comparatively less in the case of R1 and the lower mids are recessed in both cases . In the treble section, the RA15 is a bit on the thinner side, Instruments has capable to produce clearly with the resolution was good. On the other side, the separation and layering of the R1 is a bit unrefined. RA15 just real winner in technicalities, Wider sound stage combined with holographic imaging makes it very competitive in this price category. R1 is technically not very strong as it is a triple dd set. Its staging was good but the imaging was of average quality. But in terms of tonality and timbre accuracy, none of the two sets will be the best, although I will put R1 ahead here, besides, the RA15 set is just far better in terms of detail & micro detailing capability.

★ Conclusion :-

The 100$ price category has become very competitive these days. Chifi brands have many offerings in this price range. NF Audio has recently become a part of this competition by launching their RA15. This set is technically better than other competitors. Currently, there are better options than this in the 80$ market because the quality of its accessories is quite low and at the same time the drive flex issue will also be a problem for many. The interchangeable nozzles they used for sound tuning could not provide a very polished sound. Especially the sound of the silver nozzle will be quite tiring for many people. I would recommend it to those who are more used to the treble's energy with prioritize excellent fit & comfort.

I've provided the purchase link below for everyone convenience

 Hifigo official store (link isn’t affiliated)

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Disclaimer:

• I don’t read FR graphs. I only use my ears, as earphones should be used.
• NF Audio sent this unit to me in an exchange for an honest, transparent review. Rest assured that this review will do its best to devoid from any bias/es as much as possible.
• The following remarks and observations shall be made and owned only by me.
• No monetary compensation is/was involved before, during, and after the period of creation of this review.
• Your mileage may (and always, will) vary.

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Burn-in time: 4-8 hours per day, 5 days.

Source/s used:

• - Non-HiFi smartphone (Infinix Note 12 G96), PC.
• - Tanchjim Space DAC
• - Hidizs S9 Pro DAC
• - Aiwa XP-V710C CD Player (12 sec. EASS)
• - Sony Xperia X Compact
• - Local Files via Foobar, YouTube Music, Deezer, and Qobuz with UAPP.

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IEM/Earbud/Setup configuration: Stock MS42 large eartips, any form of EQ or MSEB off, 40-60% volume.

(Additional note here: I will be reviewing the RA15 first with its preinstalled silver filter, then compare my findings to the additional gold filter).

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Sound signature:

• The NF Audio RA15, in its stock silver filter, exhibits a fairly neutral sound signature that leans to the brighter side of the spectrum. On certain setups and ears, it may sound as a mild-v-shaped, bright sounding set.

Lows:

• First things first, the NF Audio will never be a basshead set and will never be the IEM for die-hard bassheads who prefer a chunky, lingering bass. The bass of the RA15 is a clean, well-controlled, firm bass, with both midbass and subbass having equal levels. This means that the RA15 also exhibits a good amount of detail and texture in this region, but does not exhibit any slouch or slow decay, which can be a necessity on some genres and tracks.

Mids:

• The mids are well done on this set. It is not too forward nor recessed, and exhibits a very good amount of presence, openness, and detail. Lower mids do not sound too thin or too thick on this set as well. Male vocals, and instruments in this region are presented well. Upper mids are elevated, with a good amount of clarity, air, and sparkle. The upper mids also exhibit mild peaks but nowhere near piercing, or certain ears and tracks. This can be a deal breaker to those who have a pair of ears that are very sensitive to upper frequencies. This however is also greatly reduced when the gold nozzle is paired or used with this set.

Treble:

• As for the treble, it is well extended, bright, and airy. This isn’t a surprise for those people who already auditioned NF Audio IEMs before because they tune this region well-done and favorable for those people who are accustomed to brighter signatures. This region doesn’t have the peaks that the lower mids have, as the cymbals seem to sound alright and not too much to my ears. Detail retrieval is above average most of the time as it renders microdetails excellently, if we are talking about IEMs under 100USD.

Soundstage, Imaging and Separation:

• NF Audio has always been one of the top performers in this department in their respective price points, to my book, at least, and it shows here in the RA15. The soundstage is wide and has a good amount of depth and height. Separation and layering is well rendered, clean, and does not suffer from any congestion or any abnormalities. Imaging is precise and has no problems rendering vocal and instrument positioning.

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Other tuning filter nozzle comparisons!

Gold Nozzle:

• The gold nozzle tones down the upper frequencies, turning it into a balanced sound signature. Bass exhibits a bit of additional chunk when compared to the preinstalled nozzle, which also adds a slight tinge of warmth to the lower mids. The peaks are greatly reduced and are somewhat gone to my ears. Technical performance isn’t affected that much as well.

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Other IEM Comparisons!

Simgot EA500 LM

• To keep things short and simple, the EA500 LM and the RA15 nearly share the same sound signature and quality. The EA500 exhibits a bit more bass quantity when compared to the RA15, while the RA15 is more detailed and brighter with the stock preinstalled filter applied. The mids is a bit more laid-back/relaxed on the EA500 LM when compared to the RA15. As for the technical performance, the EA500 LM is wider in soundstage when compared to the RA15. The rest is more or less the same in terms of level of quality for their respective retail price.

TangZu X HBB Xuan NV

• These two sets are literally night and day in terms of their overall sound. The Xuan NV is thicker, warmer in sound, a bit harder to drive IEM when compared to the RA15. The RA15 leans to the brighter side of the spectrum, more resolving, and better in technicalities, while the Xuan NV has smoother, lush, sound to it.

Tanchjim 4U (on monitoring filter)

• The Tanchjim 4U on monitoring filter is a flatter, thinner sounding set with an evident sub bass roll-off. Technical performance is better on the RA15, but the Tanchjim 4U has better transparency in mids.

KZ ZS12 Pro X (standard version)

• The KZ ZS12 Pro X actually shares the same sound signature when compared, as both sets can sound mild-v-shaped that leans to a brighter spectrum most of the time. However, the NF Audio RA15 has more energy to it, making the ZS12 Pro X sound a bit “reserved” when compared side by side. Surprisingly, both IEMs share the same level of technical performance given that the ZS12 Pro X sports only 1 dynamic driver per side, while the ZS12 Pro X is hybrid configured IEM.

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Pros:

• A well-balanced, all rounder yet technically capable IEM!
• Clean, detailed sound!
• “Relatively neutral” sound signature (on preinstalled silver filter).
• “Balanced” sound signature (on gold nozzle filter).
• Tight, speedy, controlled bass response.
• Open, detailed mids, the NF Audio way!
• Bright, airy upper frequencies!
• Excellent technical performance under 100 USD!
• Straightforward yet effective modular tuning nozzles!
• Very good fit, comfort, and isolation.
• Durable, premium build quality!
• Premium quality accessories!
• Cohesive, minimal packaging!
• Easy to drive!

Cons:

• Upper frequencies can be peaky to some ears.
• QDC connectors slightly ruins the aesthetic (nitpick, subjective)
• An included hard case would’ve been nice treat (nitpick, subjective)

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The NF Audio RA15 in my honest opinion, is a very competent IEM under 100USD. This IEM, to my ears, shares the same DNA that its older, more expensive sibling, the NF Audio NA2+ has. It is eerily close to that IEM but has noticeable differences when compared to the pricier set, such as its smaller soundstage as an example. So, if we are talking practically, the NF Audio RA15 will please and cater those people who want a bright, resolving, technically competent IEM under 100 USD! I also looked at the bigger picture and the RA15 holds itself on its own really well, along with the other popular, noteworthy IEMs within the same price range, 100 USD and below. Very remarkable and competitive NF Audio, but in a really good way!
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Pairing recommendations:

• Source: The NF Audio RA15 is bright sounding IEM, and it is easy to drive. Any warm-sounding USB DACs and devices will suit this well.
• Eartips: The eartips are more than enough for the most part, but it does feel a bit shallow to my big ears sometimes.You may use your preferred eartips.
• Cable: The cable in my opinion is well-done as it is not too thick, bulky, and not too thin either. You may still use your preferred cable.

Thank you for reading!

Non-affiliated link here: https://hifigo.com/products/nf-audio-ra15

Additional Photos Here: