NF ACOUS NM20

Introduction to the NF ACOUS NM20 Review

NF ACOUS is quite an unknown brand today, and not without reason. It’s been a while since something new from the NF team came about. But now, here we are – NF’s latest offering, the NM20, is now in my hands, and I have a few things to say about it. Not only that, but I also have to mention the available product line because there are some surprises to be had there. 

The brand itself, originally named “NF Audio”, was founded in 2014 in China, becoming one of the first custom IEM brands from the region. Since then, the team at NF Audio provided the market with some popular gear, as their website states – in 2015, the NF3 became China’s leading custom IEM, in 2016 a proprietary balanced armature driver was introduced, but the most intriguing thing came about in 2021 – NE4 Evolution, an IEM with exchangeable faceplates, each providing changes in sonic performance. Maybe one day I’ll get my hands on those, who knows…

NF Audio also collaborated with franchises like Assassin’s Creed, marking their venture into the gaming world. Afterward, after a period of silence, another announcement was made – NF Audio has been renamed to NF ACOUS. Together with a new name came new products, like the NM20 which I am currently reviewing. If you scroll through NF ACOUS’ website, you will see that nowadays the brand seems to be focused mostly on professional use, with models like the NM20 and NM2 taking up a lot of space on your screen.

If you want to learn more about things like brand philosophy, achievements, et cetera, check out their website. There are also quite a few bands sporting NF ACOUS gear on stage, but unless you’re familiar with far-eastern music, those may not exactly be household names to you. Well, maybe you’ll come across something new and refreshing.

Packaging

The packaging for the NF ACOUS NM20 is quite shiny and full of inscriptions and images, most of them highlighting the NM20’s intended use – on the stage. I’m no musician, so I had to resort to more simple listening sessions, but thankfully, they work well even if you’re not on stage. No one checks that when you buy them, apparently. Inside a colorful sleeve is an even simpler black box with the brand logo on it. It opens up like a book to reveal all the accessories you get with it, and something I find very pleasing aesthetically – the IEMs embedded in a round piece of foam, which very closely resembles a CD. For real, the first time I opened the box I actually thought it included a CD (shoutout to Blaz Erzetich).

Despite there being no CD in the box, the accessories are plenty, and they are of satisfying quality. With the IEMs you get 4 pairs of silicone tips in different sizes, an instruction manual, and a fabric-covered pouch with the brand’s logo turned into a metal patch smack-dab in the middle. Philosophy about carrying pouches for IEMs differs from brand to brand, but this is a solution I could easily see in a more pricey set of IEMs – perfect combination of size and security, no space wasted, and fits elementary stuff like a 1/4in adapter and a small dongle inside. The cable itself is pretty good as well. It surely beats stuff like the stock cable included with the 16 times as expensive Hifiman Svanar, but it’s not the best cable I’ve ever seen to come with an IEM. It is most definitely an adequate solution given the budget at hand – a 5N OFC cable with 2-pin connectors recessed into a small enclosure. 

While we’re on the subject of unboxing things, together with my NM20, Paul from NF ACOUS (an absolute joy to work with!) hooked me up with a Kazoo, labeled on the website as KAZOO 01. That certainly isn’t something that I’ve had on my Bingo card of accessories made available by IEM manufacturers, but now I own one. After learning how to actually use the thing, and a couple of interventions by the police after numerous noise complaints, I have decided that a career in music production may not necessarily be my calling. I’ll stick to reviewing headphones. Nevertheless, the Kazoo is surely a conversation piece among the lineup proposed by NF ACOUS. Points for creativity right here.

Design, Build Quality and Tech

The design of the NF ACOUS NM20 reminds me a lot of a certain era in computer hardware design when everything had to be made with translucent colorful plastic, revealing what lurks inside the enclosure of whatever you were looking at. This is especially true for the blue colorway, which I currently have on hand. The NM20 can also be had in pink and gray, each colorway sporting translucent plastic of course. I consider it nice to take a trip down memory lane, back to the days when having a computer looking like that was one of my biggest dreams. I was broke though, because I was 3. I guess I should have began investing in real estate back then.

The NM20 is not only pretty, however, as it is also comfortable. The shells are very lightweight and their shape is inoffensive, which makes me consider these suitable for most users’ ears. The shell is neither too small nor too big, and the insertion, while not the most shallow, is not very deep either, which is fine by me. At least it’s not as bad as whatever Etymotic comes up with. The build quality itself is pretty good, though not exactly a standout feature of the IEM, seeing as you can shoot for 3D printed resin-like IEMs at a similar price range. That’s not to say that there’s anything wrong with the build quality, everything is fine in that department, and despite being made 100% of plastic, the sturdiness should leave you with no worries whatsoever.

The tech department is quite simple in the case of the NF ACOUS NM20. The pair sports a single dynamic driver per side, no weird combinations or exotic drivers to see here. I find that to be a good solution. One well-tuned dynamic driver is lightyears ahead of a mixed bag of a million balanced armatures jammed into a 30-dollar IEM. Hell, some of the time you don’t even know if there are indeed as many drivers inside as advertised… With a limited budget of 120 USD, I would definitely prefer to have one well-tuned driver than a whole host of random junk in the shell. Good choice!

Sound of the reviewed NF ACOUS NM20

Summarizing the NM20’s sonic performance, the IEM seems to shoot for a neutral sound signature with a slight boost to the highest registries. Oftentimes the NM20 may shock with the amount of detail pushed in the treble, while other facets of sound remain dynamic and clear, with no evident boost to any certain frequencies. To test the NM20 I have resorted to using my trusty ol’ Luxury&Precision W2, and an Apple dongle for my coffee shop ventures, occasionally making use of the Angel by Earmen as well. I’ll delve deeper into the pairings discussion down the line.

BASS

The bass of the NM20 seems to show its teeth especially when it comes to technical performance. The sound is crisp, fast, and clean. The lower registries never leak into the midrange, punching hard and fast, while knowing their place on the stage as well. “Violence” by Andy Stott is a perfect example of how it happens. At certain intervals, Mr Stott seems to have pushed the viciousness of the bass to the maximum, intending to give it a towering and gargantuan characteristic. The NM20 handles it with ease, which is something I did not anticipate at this budget, but I guess the market keeps on evolving. The bass maintains its presence and remains highly pronounced, whether it’s the towering monster or simply an addition to the musical arrangement, and keeps everything clean, allowing other aspects of the music to shine.

There is a small bone I have to pick with the bass though – the extension. “Miracles” by Mala, my reference track for sub-bass extension, captures the issue quite well. At certain moments when the bass is at its lowest, the notes seem to roll off a bit too fast to consider the NM20 perfectly extended. It’s not the worst extension by any means though, and the dynamic driver still keeps it all together well, providing a clean and snappy reproduction of the low registries. Also, the bass response itself is tactile and dynamic, but I would’ve liked to see it hit ever so slightly harder. I guess it boils down to bringing up the sub-bass a bit. Still, the bass response is praiseworthy for its cleanliness, control, and simultaneous dynamism and tactility. 

MIDRANGE

In terms of the midrange reproduction, the NM20 seems to put all its skill points into technical performance here as well. The midrange is smooth but there is no coloration or warmth to be found – it’s neutral, as could be expected from a product intended for professional use. What I enjoy the most about the midrange of the NM20 is its clarity. Even in more complicated musical arrangements, like Kanye West’s early work on The College Dropout or Late Registration, despite a lot happening at once, the NF ACOUS NM20 remains clean and precise, not letting any clutter or claustrophobic sensations to come in the way of a smooth listening session.

The lower midrange benefits a lot from the bass’ clean and controlled nature, making male voices and certain electric guitars stand out. And, similarly to the bass, the lower midrange is very well-controlled – it never seems bloated or loose, as it may sometimes happen with gear that tends to boost the lower mids too much. The upper midrange, however, like the electric guitar in Chris Stapleton’s “Cold”, comes in with a ton of sparkle and life, leaving the harshness behind. Man, the chills you get when listening to this track are like getting hit with a taser. Despite the intensity of the spectacle, there’s not a lot to be desired in terms of the detail retrieval, which is also a standout characteristic of the…

TREBLE

…treble. Yeah, this, in my opinion, is the absolute best aspect of the NM20’s sound. The detail in the treble is so intense for the price, that it may give some of you the sensation of “hearing things you haven’t heard before” in certain tracks. That’s always quite a shocker. One of my favorite tracks of all time, and surely one of my favorites to listen to on the NM20 as well, is “Moth” by Burial and Four Tet. The latter mentioned that “Moth” is the single best piece of music he had ever worked on, and even at your first listen you may see where he is coming from. As the track progresses, revealing more and more to the listener, numerous treble-intensive instruments appear, putting additional  emphasis on treble reproduction, thus making the NM20 shine. 

“Moth” is an easy track to reproduce well, but difficult to reproduce exceptionally well. The treble performance of the NF ACOUS NM20 reveals a lot about the piece that may have been hidden from many listeners up until now. The bell hits throughout the track seem like flashes of light, shining through the whole production with the amount of detail and dynamics being displayed. For this beautiful, tactile, and sparkly treble to happen, it needs to stand out. And it does, not in a bad way – despite its liveliness, the treble seems to keep a safe distance, refraining from threatening the listener with sibilance and harshness. Bravo.

SOUNDSTAGE

The stage of this IEM is not the largest I’ve ever heard, but it’s very well reproduced for the price, remaining competitive even in higher price brackets. The soundstage of the NM20 expands to the right and left quite a lot, but it’s not the deepest. Still, the instruments have plenty of space to shine, and a left-right extension of the soundstage is still a pretty good way to handle it. Infinitely better than if it wasn’t extended at all, or, even worse, contributed to a sensation of being boxed in with the sound. Thankfully, that isn’t the case. 

What also helps with the spaciousness of the stage is how clean and well-separated the sounds are. The reproduction of space seems effortless when everything is controlled properly, but I would’ve liked to see what would happen if the sub-bass was slightly less rolled off from the get-go. Still, as it stands, everything is clean and tidy with a sufficient amount of air, so no complaints here from me. This pair does a good job of reproducing live recordings, and I can only imagine that it would fare well in a professional setting with everything being kept clean.

Pairings

NF ACOUS NM20 is an easy IEM to drive. Even something like an aforementioned Apple dongle can do a sufficient job of making those play sounds and all, but I would only consider it a viable option if you are in a shortage of mobile devices to plug your IEMs into. If, however, you want to step things up a notch, get a dongle that’s intended for actually driving the IEMs, not just letting them play.

Nowadays good dongles get cheaper and cheaper, and the expensive ones push the ceiling for mobile performance even higher. Amidst all of that happening, I am still more than happy to use my L&P W2, and I consider it the prime choice for something like the NM20 – it provides a certain substance and slight thickness to the sound, but doesn’t drown the treble with additional warmth of the midrange or bass boost. If you can opt for something neutral yet natural, with a boost to the dynamics, that would be my choice. Of course, you could even get something more fancy, like the Earmen Angel I’ve mentioned before, but as great as it sounds, I find the dongle to be more versatile in terms of use cases, so the W2 remains my choice, despite the Angel’s might.

Comparisons

Meze ALBA

The Alba has remained a benchmark for me in terms of sub-200 USD IEMs. However, it’s worth to note that the Alba is a whole 40 USD more expensive than the NM20. With that taken into account, I consider both of them to be pretty good contenders for their micro price ranges. Your choice should depend on what exactly you’re looking for, as both have their advantages. The Alba shines with versatility, satisfying note weight, and engaging sound, while also keeping a better extension of the lowest registries than the NM20. The latter, however, seems to beat the Alba in many cases with perceived detail retrieval and a lively and dynamic treble, keeping things lighter and slightly more airy in other registries. It’s also a matter of deciding whether you prefer a light, neutral sound with a slight treble boost, or a fuller, well-extended, slightly V-shaped signature. All that being said, I think both of them deserve their own praise.

NF ACOUS NM20 Review – Summary

The NM20 stands out with its treble reproduction, as I think it’s some of the best on the market at the price range, contributing to great detail, air, and spaciousness. You don’t have to be into pro audio or become an audio engineer to appreciate that, despite those IEMs being marketed mostly for professional use. 

At 120 USD, I think the NM20 by NF ACOUS does a very good job of providing a clean, technical, neutral sound with a slight lift to the treble. The weak spot of the NM20 is the sub-bass extension, but the IEM makes up for it with a clean, precise, and powerful presentation of the bass.

Aspects like the build materials, accessories, and build quality are decent, but not exactly the best to be had at the sub-200 USD price point. Nevertheless, I can maintain a clean conscience and still keep it real labeling those as…recommended.