NF Acous NM25 IEMS Review – Rather Light And Bright
NF Acous NM25 is a $199 USD pair of IEMS or in-ear monitors with a dynamic driver at the core, a high SPL and low impedance, dual magnetic circuit and dual acoustic chamber designed by NF Acous. Today we will explore the sound and fit of the NFAcous NM 25.
Introduction
NF Acous has been creating IEMS and In-Ear monitors for a long while now, the new NM25 being a completely new adventure for them, as they are working more with tuning and acoustic chambers. NF Acous products can be found on Amazon, Aliexpress, and other similar outlets also, as they are a widely popular entry-level earphone designer with a strong track record.
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Product Link
Amazon – https://amzn.to/4pY6UX3
Build Quality – Design
NF Acous designed the NM25 to be a premium metallic IEM with a single piece of aviation aluminum, carved by a 5-Axis CNC process. It has the MC2L-100A dynamic driver at the core, with a special Dual Magnetic Circuit, Dual Acoustic Chamber and a new damping system for the best tone from this driver. Combined with the new Clutter TRAP 2.0 tech, which acts like a physical EQ, this new IEM should deliver a smoother and cleaner sound.
NF Acous did not stop there and they even included a special circuit that reduces the reflected sound, having 5 air pressure damping nets and 2 tuning sponges. You will receive good silicone tips, a transport case and a 3.5mm single ended cable also.
Technically, NM25 has a dynamic driver at the core, uses a Silver Coated OFC cable and has a SPL of 108 dB and an impedance of 32 OHMs, with a promised isolation of 25 dB. They also have a THD lower than 1% with a max SPL of 125 dB.
Subjective Usage
Wearing the NM25 I noticed that they are quite lightweight and fit nicely inside of my ears having a medium insertion with a good eartip and cable quality. They are quite similar to all of the NF Acous IEMS I reviewed including NE4 being like a mini NE4 in person.
I feel like the fitting is not that secure, which means that the passive noise isolation is at max around 20 dB, and they also are incredibly sensitive to source noise, showing noise with most sources, a background hissing.
Sound Quality
Pairings – I have paired the new NM25 with the most recent sources I have reviewed including FiiO K17, Argon Audio SA-2 Amplifier Driven by FiiO Warmer R2R, Acer Nitro 18 AI Laptop (with 3.5mm adapters), iBasso Kunlun, FiiO Snowsky Echo DAP, Orchard Audio Valencia driven by Musician Pegasus III and Luxsin X9
I would rate NM25 to be as easy or hard to drive as most IEMS, but they are more sensitive to source hissing and noise than most. The sound combines well only with the warmest, thickest and smoothest sounding sources, so make sure you don’t have a bright sounding source if you buy them.
Overall Signature – Sonically, NM25 is extremely bright and will pierce the skin, ears and sound really revealing, detailed, but with so much treble that they will only work well for music like rock, metal or when you have a hearing loss and want to get back those nice cymbal crashes, or when you really want them to stand out. I like it for certain bands, it makes me go back to my post-hardcore favorites, but does not work well for most music, especially new and music with a strong dynamic compression.
Bass – With a bass starting at around 40 Hz, NM25 simply does not have a lot of bass and the bass has the lowest presence and amount in the mix, as they sound snappy, airy and quite piercing. This means that the bass that is there is fast and moves as fast as the midrange and the treble. It is not dry but it is not much in amount.
Voicing And Midrange – Voices are more present than the bass but less present than the treble, which takes away some vocal focus and forwardness. This works well if your music is older and less compressed but results in a piercing sound if you’re listening mostly to new rock and metal music. It is great for classical and music with less dynamic compression. Female voices have more presence, owed to the really strong upper midrange and lower treble.
Treble – Treble is the most forward part of the sound, and this creates a really bright tone, but something I noticed only while listening to the NM25 is that they work really well with ACG and J-Pop as well as J-Rock. This makes me think that they were mastered and designed for those styles, as they are hugely popular in China and ASIA where the NM25 is marketed for.
Dynamics And Textures – Dynamic range is very wide and there is minimal compression, but textures are not dry, despite the sound being so bright. Quite on the contrary, the sound can be rather splashy and not the fatiguing type. This works well as it balances out and dampens the aggro end of things allowing NM25 to be enjoyable and a bit musical, especially for ACG music styles.
Loudness Saturation Gradient – Although NM25 has a much lower distortion and THD than promised, they actually sound best at low and medium volumes and you will not be able to take them too loud, since the tuning itself is a bit too aggressive and bright, making them sound best if you prefer quiet or medium level listening.
Soundstage – Staging is one of the aspects that saves the NM25, as they sound quite open and wide, having a good instrument separation and clarity. While not necessarily holographic, NM25 is enjoyable with most pop, ACG and new music from a staging perspective.
Value – Conclusion
Considering the price point, NM 25 is very much a dedicated and niche pair of earphones. You need to know you would like this type of tuning as it is not universal and it will be a top favorite for some folks, a breath of fresh air for others, but will not complement every single collection out there.
I like what NF Acous did with the NM25, but I listen to quite a bit of ACG and bands like HimeHina which allow them to shine. If you like Vtuber songs, or Vtuber voices and shows in general, you will love NM25, yet if you are someone who follows a mainstream taste, you might find their sound too bright and not the best combo for your collection, and NF Acous has the NE4 which works much better for a more commercial collection and which you can even tune to sound more balanced.
PROs
- Good resolution and a crisp treble
- Wide soundstage and instrument separation is respectable
- Thin but reliable cable
- Excellent build quality
- Comes with a transport case
- Sharp treble with top extension
- Bass extension is good despite the low quantity
Cons
- Very bright and nice tuning, works really well for certain styles like ACG, or old rock, but does not complement every single style out there
Product Link
Amazon – https://amzn.to/4pY6UX3
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Full Playlist used for this review
We listened to more songs than those named in this playlist, but those are excellent for identifying a sonic signature. I recommend trying most of the songs from this playlist, especially if you’re searching for new music! The playlists are different for Spotify, Tidal and Youtube, and based on the songs I enjoy and are available on each!
https://www.youtube.com/playlist?list=PL_cjBXGmwSHSdGcwuc_bKbBDGHL4QvYBu
https://open.spotify.com/playlist/5J3oloz8Riy9LxEGenOjQ0?si=979ba4f082414be7
https://tidal.com/browse/playlist/330fd544-8e5b-4839-bd35-676b2edbb3d5
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