• The artwork on the outside is exquisite, for it has a wham of colours whilst still being minimalistic. In a nutshell, this is a box worthy of being displayed on shelves.

• The box is a big step up in size and finish compared to budget models, such as the KZ Dawn (makes sense since the Mermaid is 66 times more expensive). “What makes it so big?”, you may ask.

• The box’s content is comprehensive and all-inclusive, housing an instruction manual, a hard water-proof case, the earpieces, the cable, a lanyard, 15 pairs of eartips of different sizes and materials.

For the full unboxing process, please watch my Youtube video (it’s only 2 minutes long)

Build quality:

• The earpieces are made out of aluminium, allowing for the impression of solidity without weightiness.

• The faceplate is either resin or plastic and is texturized to represent fish scales.
• There is also a protruding part which symbolizes fish tail and is solely for cosmetic purposes.

• Personally, I dislike the stock cable of the Mermaid, the reason for which being the ribbon form factor and its enduring memory. Besides, the termination is 3.5 mm and unswappable, which is somewhat disappointing should the $300 price tag be true. For reference, their $50 TRN Starfish has a modular cable.
• The 0.78mm pin connectors also fit quite loosely into the earpieces, which reduces the Mermaid’s premiumness.

Fitment: Generally speaking, the shells, having to house 4 drivers, are bulky and protrude significantly from the ear. Because the housing doesn’t conform to my anatomy, the stability is almost entirely tip-dependent. Speaking from experience, I have tried budget IEMs with better fitment than the flagship Mermaid.

Sound quality:

Sound signature: (V-shape)

• Bass: The bass on the Mermaid is crispy, quick and compact. Despite the large mid-bass quantity, it is not bloated but rather deeply impactful thanks to its definition, transience and resolution. There is seemingly no bass bleed into the midrange despite the graph suggesting otherwise.

• Midrange: The lower midrange is accentuated, lending the instruments a warm sonic profile. Personally, I prefer it to be a bit lowered for a smoother curve. On the other hand, the upper midrange is attenuated compared to the Harman target, constituting the new tuning meta pioneered by Super Review. Subjectively, I prefer the midrange executed in this manner over compliance with the standard Harman target. In real world testing, I could hardly ever hear vocals being shouty.
• Treble: There is a Himalayan peak around 8khz, which allows for an analytical sound at the cost of being incisive. In my own experience, sibilance is not a major issue. However, I often experience treble fatigue after 30 minutes of music playback at standard volume. As a result, it is recommended that this pair be played at lower volumes and that treble-sensitive listeners be cautious before making the purchase.

Soundstage: The soundstage on the Mermaid is shockingly expansive thanks to the two tiny holes in the shell and the planar magnetic drivers, making it perfect for gamers and music enjoyers alike.

Detail retrieval and imaging: Thanks again to the planar magnetic drivers, micro nuances are easily heard and instruments can be told apart, even in busy songs.

→ All in all, the TRN Mermaid possesses a crystal clear sound profile and is extremely versatile. On songs whose bass I have hitherto only thought of as dirty such as “Murder in my mind” by Kordhell, the Mermaid impresses with deliberate and energetic rumbles. On songs with a plethora of contemporaneous instruments playing like “Chutzpan” by Avishai Cohen, it shines with impressive resolution and instrumental separation. The sound is spacey but not overly clanky, bassy but not boomy, pleasantly surprising me for its clean presentation.

Comparisons:

Against NiceHCK Tears ($30):

• Though the cable on the Tears is made out of a cheaper material, it ended up feeling nicer compared to the Mermaid’s, which is unsurprising since in my opinion, the Tears’ cable is the best I have ever held.
• I prefer the sound signature of the Tears over the Mermaid’s. Whilst the Tears’ sound is not as crystal clear nor spacious, it is simply more pleasant and smoother to listen to for extended periods of time.
• The Tears is also going to fit more people’s ears thanks to its small form factor.
• Everything else, including build quality, accessories and detail retrieval is done better on the Mermaid.

→ The Mermaid should not be nearly 7 times as expensive as the Tears.

Against Tinhifi C2 2025 (40$):

• While the C2 is airy, lacks crispiness and resolution, the TRN Mermaid is basically an improved version with added treble spiciness.
• The build of the Mermaid slightly edges out the C2.
• The cable on both is equally bad.
• The C2 hugs my ears’ anatomy better than the Mermaid.
• For long listening sessions, I would still prefer the C2 for its less strenuous sound signature.

→ For me, the Mermaid is something only intended for special occasions when there is a need to hear all of a song’s nuances. On a daily basis, however, for casual listening sessions, I would still pick some better-tuned sets, their cheaper price notwithstanding.

Verdict:

• The TRN Mermaid is a decent pair of IEMs that come with a well-rounded package. Nevertheless, the competition at the $300 price point is fierce, and the Mermaid will not be the definitive selection for sound quality at that price. As a matter of fact, the $100 Fosi Audio IM4, which I am about to review, stay tuned for that, is expected to punch well above its weight and render IEMs like the Mermaid obsolete.

Final score: 3.5/5 (Wanna see how this compares to other IEMs? Click here)

Songs I listened to for testing:

• Center Mass - Twenty Øne Pilots
• Heavy is the Crown - Linkin Park
• Smells like teen spirit - Nirvana
• Metamorphosis - INTERWORLD
• The Timeless Machine - Linkin Park
• Papercut - Linkin Park
• Murder in my mind - Kordhell
• Chutzpan - Avishai Cohen
• Running Up That Hill - Kate Bush

Thank you for reading my comprehensive review. If you find this article helpful or want to contact me, please click this link to buy me a pair of eartips or find my contact information.

Thank you, and I’ll see you guys next time!