NiceHCK M6 English Review

Green Velvet




Construction 90%
Comfort 80%
Accesories 70%
Sound 90%
Quality/Price 90%





  • Sound profile.
  • Remarkable scene and image, clarity, separation and detail.
  • Very natural mid region.
  • Excellent quality/price ratio.
  • System of filters to modify the sound.




  • The cable does not allow the potential to be extracted from the EMIs.
  • The low range could improve in sub-bass extension, linearity and decay.
  • The filter system is not exploited: only part of the frequency range is modified.



Purchase link


Link to the Store





  • Driver Type: 2 Dynamic Drivers 10mm + 4 Balanced Armature
  • Frequency response: 20-20000Hz
  • Sensitivity: 106 ±dB/mW
  • Impedance: 17 Ω
  • Jack connector: 3.5mm in L
  • Cable length: 1.2m
  • Earphone interface: MMCX





The M6 comes in a shiny brown box completely sealed in plastic. The logo of the brand is engraved in silver. Behind it only comes a white sticker with the minimum specifications. Inside is the classic NiceHCK zipper box. In it are the IEMs with the connected cable and a pair of medium silicone eartips. He is accompanied by 4 more bags. One with three pairs of narrow diameter yellow core silicone eartips, sizes S-M-L. Another one with two pairs of black silicone eartips with wider core, sizes S-L (the pair M comes in the IEMs). A bag with two foam eartips and finally another bag with two pairs of filters Gold and Silver. The third pair is screwed to the IEMs and is the same color as them.

It is a similar presentation to other NiceHCK products but with a more attractive box and a well-protected interior made to measure.



Construction and design


The capsules are metallic and lightweight, smaller in size than they appear. They are IEMs, which simulate the internal shape of our ears, very rounded and pleasant. The construction seems quite robust although they are very light. The MMCX connectors have good quality and the adjustment with other cables is done in a firm way and without looseness.

The IEMs have interchangeable nozzles. After they have been unscrewed, they can be replaced by another pair in order to modify their sound. The standard installed pair is the body color of the IEMs and provides the reference sound. Gold-plated mouthpieces offer softer treble and silver-plated mouthpieces with more treble.

They are designed to be worn with the cable over the ear.

The cable is composed of two thick wires of dark copper covered with transparent plastic. Both wires are braided to the splitter. Behind it there is a pin to help the adjustment under the chin. After the splitter, the cables reach the connectors smoothly. In the over-ear section they are covered by a slightly thicker plastic sheath that provides the necessary rigidity to maintain the fit. The jack is L-shaped in a combination of metal and plastic. The cable looks of a good quality that presages a good sound. In the end this is not fulfilled, being the weakest link of the whole, because the sound of the IEMs, after being replaced, clearly improves.



Adjustment and ergonomics


The shape tries to be ergonomic, but for me anatomy remains halfway to the perfect fit, due to its compact size. I still think it’s personal. However this has not been such a negative point because I have only felt some discomfort after a long time with them on.





The sound is delicious to my ears. I’ve been trying out headphones for a long time and looking for something that will make me forget the idea of analyzing their sound. This time the M6 has done it, once fitted with the right eartips, when the sound has started to flow, any hint of critical judgment has disappeared and I’ve just concentrated on the music. Music, finally! And so a few days have passed.

Now I have to think about its sound and I feel lazy. Why try to describe a pleasant listening sensation?

There is part of the sound that fits the personal preferences described at the beginning of this review: The bass is wide and large, suitable to my tastes. Perhaps I would have preferred something more sub bass or something more precise and faster decay. The treble is very soft to my ears and in the most sibilant recordings has been very far from causing me any discomfort. The voices are quite complete but somewhat behind the gain of the bass, which interferes with a point in the mids. They are not analytical headphones nor with great precision, but they tend more towards the warm and musical side. In my personal opinion I think that their sound is very soft, comfortable and pleasant, in these aspects they move away from an extremely high level of detail.




Warm V profile.




The bass is wide and warm, its great presence begins in the mid bass and extends in gain to the mids, where it meddles a little. This area reminds me a little in the presence of the Toneking TK12s, without reaching their level, but giving a pinch of that massive sound that characterized it.

The sub-bass extend with enough presence up to 40Hz, below which the gain drops significantly. While at the other end it remains quite linear up to 100Hz to slowly fall towards the midrange. So the bass is not the deepest nor does it have a great precision, but it is a little diffuse and not very laminated. As for the speed would be above average, although the decay is not so good, getting to mix a point with the mids.






The lower mids start with quite a gain from the lower zone, descending smoothly, which makes male voices have a very good presence. Moreover, at no time do I find any hint of mud in them, but they are warm, with a very musical and natural timbre, a fairly sweet and soft texture. The female voices are a little behind, but they keep their same characteristics.

In spite of being IEMs in V the mids shine, but not by the presence of the treble, but by themselves, by their own exuberance and wealth. The resolution of the area is remarkable and exceeds in definition, detail and clarity to the bass area.

The right part of the V is represented by the classic enhancement in the high mids, without this implying something negative. Contrarily this peak is fully controlled and conveniently smoothed. The result of this is the delicacy with which the mids is executed and its richness in nuances and details. It’s, therefore, that soft V that characterizes the profile of the M6.





The treble start their fall, almost free, from 6kHz. Did I tell you that I like polished highs? Here they are: absence of wheezing, penetrating trebles, knives, crystals, needles. The only thing I could miss is some more air to gain in detail and precision.



Scene, soundstage


Wide and high scene, good depth and instrumental positioning. The drivers do a great job on the directionality of the sound and the stereo image takes advantage of such virtues.

The sound is clear and detailed, but it is not until the micron, its analytical capacity does not reach such a point, because it is not its profile. But for all the warmth offered by the level of precision is remarkable.





The filter whose color coincides with the body of the IEM, the reference one, offers the sound that I like the most. The sound described above has been produced with this filter.

The Silver filters soften the bass and enhance the high mids, gain with them some more definition and cut the overall warmth of the set. They are a good choice for those who find the M6 too soft, as they bring something more sparkle and liveliness to the sound.

The Golden filters, on the other hand, reduce high mids. And although they seem to be designed to provide greater gain in bass, I don’t find that to be the case with reference filters, but almost the opposite. I think bass is reduced to a certain degree. But the biggest difference is in the gain cut in the upper mids. Some might like the result, but I think that with this filter some virtues of the M6 are lost because it produces a sound with less spark, perhaps more balanced, but also more boring.





1More Triple Driver


Within the price range the 1More are other warm W-profile headphones. When I bought them I placed a lot of hope in their sound. The first negative point I found in them was their fit, their wide channel made it difficult to fit in my ears with the standard eartips. There began a long search that has ended not long ago with my homemade hybrid eartips. The second negative point was the mids, I expected that having 3 drivers the mids would gain in presence and details. But that was not the case. The Triple Drivers are warm headphones that offer greater darkness than the M6, this aspect is perceived instantly. There is a big difference in the mids, the 1More are more backward, more diffuse and more congested. They even have less brightness in high mids, with the level of detail being lower. At the only point that would highlight the 1More above the M6 would be in the lower zone, I think they extend more deeply.

The scene is more claustrophobic in the 1More, they have less clarity and detail. The image is not as open as in the M6.

Ultimately the M6 are like I expected them to be the 1More.






Other classic IEMs in warm profile are the MA750. The first thing you notice after trying some and others is that the MA750 are somewhat more aggressive in the high mids area, have less bass, less scene and separation and are less warm. There is more transparency in the M6 but it is true that they look somewhat dark, offering a more bassy profile. The voices seem more advanced in the MA750 but are somewhat more aggressive and strident, less controlled. At higher volumes or in passages with greater dynamics, the MA750 sound less precise and more aggressive.

Really the mids is not that they are more or less backward, the difference is that the central part of the bass is more prominent, almost more so, in the M6 with respect to the MA750, for that reason it gives the sensation of distance in the voices.

The treble in the MA750 is sharper and more penetrating, offering that more aggressive sound, somewhat more unpleasant in comparison.

The sub-bass below 40Hz is somewhat more audible on the MA750, but when that barrier is overcome upwards, the M6 show their power in that area.

In general, the MA750 offers a simpler, more focused sound with fewer nuances. The M6 offers more richness in sound, more complexity, more detail, more amplitude, more resolution. The scene is clearly widened and the positioning of the instruments is focused, being more precise. The definition of sound in the M6 clearly beats the MA750. In conclusion, one could say that the MA750 sound more 2D, while the M6 sound more 3D.

Although the sound of the M6 is generally more bassy, the evolution is clear and the most amount of drivers is noticeable enough in the final sound.


Dunu DN-1000


Other great classics, this time also with three drivers, are the DN-1000. From output the DN-1000 are less deep in sound, narrower, more congested, somewhat more balanced from bass to mids. They also have a more linear bass, which lowers more and does not have that hump that the M6 do have. The bass extends more to sub bass level, is perceived more balanced, very good quality, faster and with better decay. While in the M6 are not perceived as complete.

As for mids, they sound more hollow, less natural, with a certain veil, cut out in brilliance. Voices lack the spark, extension and realism found in M6. The sound in these media is flatter. The M6 enjoys a greater richness of nuances and details, omitted or excessively softened in the DN-1000.

The high mids end up quite filed in the DN-1000 but there is a peak in the highs around 9-10kHz that makes the cymbals sound somewhat strident, somewhat unnatural. While the high-mids are more prominent on the M6 without becoming sibilant at all. This provides the highest level of detail. On the contrary the M6 lack peaks in the treble that produce undesirable effects.

Again, in this case, it can be concluded that the greater number of drivers in the M6 produces a positive effect offering greater detail, clarity, separation, width and depth in the sound, as well as three-dimensionality, compared to DN-1000. In my opinion the only thing that the Dunu surpasses the M6 is in the low frequencies.





The NiceHCK M6 are the IEMs I have that best suit my personal preferences, that’s why they deserve 5 stars. Are they perfect? No. Can they be improved? Of course, the bass could be more linear and extend more towards the sub bass and not be so prominent. The mid and high treble could also have some more presence…With these improvements, a better cable that doesn’t limit its potential and a more complete packaging, the M6 could cost twice as much and compete in another league. But they cost about $100 and in that range I haven’t heard anything I like more yet. And I can say that I’ve heard of higher priced and perhaps technically better IEMs, but for now none of them fit my profile as well as these. That means two things: one, that I have yet to try many other IEMs, and two, the M6 are magnificent IEMs.


Sources used during the analysis


  • xDuoo X3 MkII
  • Audiodirect Beam