100 €

Review published:




per Side






19 Ohm











102 dB








Daily Life


20 - 40000 Hz


YINYOO doesn't get sloppy, and releases an IEM like NICEHCK (M6) and BGVP (DMG) which uses two dynamic and 4 BA drivers with the difference, that there are no interchangeable filters to influence the sound like the DMG or M6 does.
It's become a bit quieter these days as far as the beat rate of YINYOO's released in-ears is concerned. So this is a possible exclamation mark to the competition, that you have to reckon with them again. Behind this exclamation mark there is also a question mark!


The D2B4 reminds a bit of the BQEYZ BQ3 in a modified form. It's quite possible that YINYOO has taken over the company, since BQEYZ hasn't been on the market since the BQ3.
They have a classic, ergonomic IEM shape and are comfortable to wear without any problems.

The In-Ears are made of metal and are currently available in blue and black. The faceplate has a ground edge where the metal stands out undyed, similar to the BQ3. This is optically chic and also makes a valuable impression. In general, the D2B4 is very well processed. No gap size, or fraying are to be recognized. The sound opening has a protruding ring to prevent the tips from slipping down.

The insulation is very good and would therefore also be suitable for stage use. The cable is a bit stiff, but robust, with reinforced earhooks and the two channels are separated next to each other (2 strands), which I haven't seen for a long time, because there are many braided, multi-core cables in circulation at the moment. In addition there is a small slider after the split to keep the cables together and to increase the comfort.


Here the D2B4 doesn't meet my (audiophile) expectations, which were created by the configuration and the general quality, but also by the price tag.

The bass is mid-bass emphasized and has a dry and soft character. It starts to generate pressure at 30 Hz, but is completely present at 40-50 Hz.
That speaks for a good portion of sub-bass. The only problem here is that the mid-bass adds another scoop and thus dominates the sound image very much. It discolors the midrange, as is the case with the 1MORE E1010. If you like bass-oriented IEMs, you might be happy here, because it still has texture and sounds quite natural, but the mid-bass increase is too strong, because even the mid-range doesn't really get there. The KZ ZS7, for example, has even more bass than the D2B4, but the mid-range is more resistant.

The mids don't have it easy in the V-signature. They get pressure from below and are also slightly dominated by the treble in the upper mids. What remains are flat and warm mids, which generally lack energy and liveliness.
Voices are discolored and seem a little emotionless. If you reduce the bass a bit, you can get a lot more out of the mids, because they become clearer and more natural. So the mids are even really good when viewed separately! The separation and also the three-dimensionality are above average, but what is the point if the bass destroys these characteristics? Then you have a well separated and spatially represented tangle of sounds. Unfortunately, I also have to make this so clear here, as we are talking about in-ears that are supposed to cost around 140 €. Already at the release date they were partly offered with 30-40% discount and even then I have a stomachache. Maybe I am a little biased here, because I currently also have the CCA C16 and the BGVP DMG in my ears, but these are in-ears to which they have to compete with this asking price.

The highs unfortunately can't give a coherent picture and sound a bit inconsistent. In the lower range are lifted and then roll off quite fast again. Towards the top, there seems to be a hilly landscape again, which provides some loosening and also contributes to the stage feeling. If it wasn't, the sound would be even warmer and more oppressive. What can be kept to their advantage is their resolution, but you have the feeling that there is a slight clash somewhere from time to time. Sibilants are again a negative subject. They sometimes play a perfidious game between aggressiveness and relaxation, there are occasional peaks where you wouldn't expect them and vice versa. This isn't exactly called homogeneous, but overall they are very solid. (Micro)Details are also a plus point of the highs, although with a deduction in the b-note, as far as naturalness is concerned.


I am firmly convinced that YINYOO will react here once again, as they have already done with the V2. Technically the D2B4 are certainly not bad, but the screwdriver must be used there, if one wants to offer the D2B4 further at this price. If you polish the mid-bass a bit and manage to smooth out the treble and make it more linear, it can become really good in-ears.
What remains is a fun-emphasized, relaxed, comparatively warm sound with 4 BA's, which has an appealing stage, plays more liberally with the right music material (depending on genre and quality) and generously provides details. In addition there is a powerful bass, which slips however more and more frequently into a boom, instead of producing a really clean kickbass, or a bass line. Here less is more. The mids suffer the most, lacking clarity and liveliness due to the dominance, although they can do better. YINYOO's aim should be to listen to it again and draw the consequences.
What remains to be said is that the D2B4 does a solid job in bass, treble and especially in the midrange, but can't hide its weaknesses compared to equally expensive models. For the price there are better alternatives at the moment, meaning the in-ears are good, but the price/performance ratio isn't good!

Note: For CHI-FIEAR fans you can buy the D2B4 for 78 € at AliExpress, which is already more realistic and quite ok. To do this, write "CHI-FIEAR" in the comment when ordering, choose "Other payment options", place the order and cancel the payment. The price will then be corrected and it can be paid with the desired means of payment.



Here the processing plays a role and the usability of the scope of supply. Additionally the appearance, wearing comfort and robustness.

Here I evaluate for me subjectively the price/performance ratio - does not flow into the evaluation!

Z: No Brainer

A: money well spent

B: all right, you can do

C: gives better for less money

D: overpriced

E: collector's price

Daily life:
Here, I focus on the long-term audibility and whether I can hear it well out of the box. This is of course very subjective and therefore only a minimal deduction or bonus. 

(-0.1, 0, +0.1)


Rating in Letters

S: 9.5 - 10

A: 9.0 - 9.4​

B: 8.0 - 8.9​

C: 7.0 - 7.9

D: 6.0 - 6.9​
E: 5.0 - 5.9​

F: 0.0 - 4.9​













Second Opinion:


CHI-FIEAR © 2020 by David Hahn

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