A different ear tip can make bright earphones easier to listen to and give their bass more substance. The NICEHCK R04 uses a narrow bore to soften sharp treble and increase low-end density. It works particularly well with aggressive tuning or a short nozzle that won’t hold a stable fit.
Tube Design with a Narrow Bore to Suppress Sibilance and Add Dense Weight
The package contents are intuitive and simple. Made from eco-friendly silicone material, the ear tips come in four sizes (SS, S, M, L) with one pair per size and color. The practical material makes them easy to clean with water and reuse if they get dirty.
Looking at the shape, they feature an elongated tube structure with a vertical nozzle orientation. The key design element is the narrow sound passage bore inside the long dome shape. This physical structure acts as the primary driver for altering the sound signature.
The narrow bore has a familiar effect: sibilance softens, the bass gains weight, and vocals get more body through the midrange. Together those changes make the presentation denser.
Hands-On Impressions: 3-Model IEM Matching Test
AKG N5005 (High-Boost Filter): The Epitome of Flaw Correction – Recommended
The N5005 has short nozzles that make a secure fit tricky, and the high-boost filter produces intense sibilance in the 7–8kHz range. The R04’s long tube shape and narrow-bore design solve both of these shortcomings at once. First, it extends the short nozzles to secure a stable seal so the fit doesn’t slip.
It also rounds off the piercing sibilance, alleviating the sharp fatigue of the high-boost filter. Achieving a proper seal also restores the dynamic driver’s bass punch that used to leak out.
There is a real trade-off to that smoother sound. The high-boost filter is meant to offer an open, refreshing top end, and the narrow opening restrains some of that airiness. If the original attraction is precisely the sharp edge and thrilling openness of that filter, softening it may not feel like an improvement. The result could instead come across as too polite or a little muffled. For me, the important distinction is whether I am trying to reduce fatigue or preserve the filter’s most vivid character unchanged. The tip answers the first aim more readily than the second.
Softears Studio4: Compromise Between Transparency and Warmth – Average
This is a monitoring device tuned with a 4-BA driver structure for extremely flat and dry sound across all frequencies. Pairing the R04 centers the sound and adds bass depth, giving substantial body to previously flat sound.
The most noticeable aspect is that the cold 4-BA sound gains cozy warmth and thickness. When listening to male vocals or acoustic instruments, it provides a densely filled sound. However, as the sound converges inward, the device’s inherent clean and transparent resolution is somewhat dulled.
The stage becomes more concentrated, which can make the space feel narrower rather than wide open. That leaves a choice about the role I want the earphones to play. For careful analysis, I would miss some of the original transparent clarity. For ordinary listening, the warmer presentation has another kind of appeal. Putting on jazz or a substantial vocal track casually can make the same earphones feel like a different, more relaxed device. That contrast is why I regard the pairing as a compromise rather than a simple upgrade or failure. It changes the emphasis toward comfortable enjoyment.
Sony IER-M500: Sound Shift That Changes the Purpose – Not Recommended
This device delivers deep, tightly controlled bass via a 5mm dynamic driver built for live stages. When the boosting characteristics of narrow-bore tips overlap with an already well-tuned closed shell, the texture of the sound changes significantly.
The combination of the flexible tube shape and closed shell does an exceptional job of blocking external noise and metallic harshness. On the other hand, the tightly controlled bass swells up, making the overall sound heavier. The increased bass quantity slightly masks vocals and other instrument sounds, reducing precise separation.
The balance consequently shifts away from monitoring and toward heavier bass. Give up a little precision, though, and the strong isolation and impact make it entertaining for casual listening.
Pros and Cons
Pros
- Significantly reduces listening fatigue by taming sharp highs and sibilance
- Long tube shape ensures a secure fit and strong seal on short-nozzle earphones
- Adds bass weight to light sounds and reinforces vocal line density
- Flexible material provides comfortable isolation without ear pressure
Cons
- Sound can become congested and muddy when matched with bass-heavy or dark earphones
- Reduces sharp edges and clarity specific to female vocals
Where to Buy and Comments
Outer diameter measurements by size may differ from the tips you currently use, so please check the detailed specifications before purchasing.
