Ikko OH2 English Review


Triple Pleasure: Design, Comfort and Sound




Construction and Design




  • Very pleasant, musical and euphonic tuning.
  • Balance and equilibrium.
  • Soft treble, very suitable for long listening.
  • Excellent ergonomics, very light weight and small size, also contributes to high comfort for long listening.
  • Good accessory set.
  • Very good capsule design.




  • The treble is too soft.
  • Intimate scene.
  • It is not an analytical IEM, its softness, both in its definition and in the treble, limits the expressiveness of the details.
  • The cable has a tendency to stiffness.
  • The oval nozzle and the special shape of some of the standard tips do not facilitate the adjustment, nor the best sound, although with traditional tips, it is very comfortable and sounds better.
  • Again, a drawing of a woman is used as a claim. It seems to be something that is becoming more and more common in some audio brands.


Purchase Link




Link to the Store






Ikko has had a very active year and seems to continue working on new products. If the other day it was a DAC/Amp, now it’s back to IEMS from the OH series. The OH2s could be the next step to those first OH1s, but more affordable, with a revamped design and inherited from their big brothers, the OH1s. Ikko’s progression seems symmetrical, not counting the exception of the OH7s: first came the OH1, were upgraded with the higher-priced OH10, without the shape and tuning changing too much. Then came the OH1s and the change was really big, both in construction and tuning. The symmetry closes with these OH2, which keep similarities in the tuning of those OH1s, although it is true that there are also differences in their design.
For this occasion, Ikko has also opted to use the dynamic driver with a deposited nano-carbon diaphragm and the patented S.V.A.S. (Separating Vector Acoustics System) technology. The capsule design is a mix of metal parts and transparent windows, through which a 24k gold-plated printed circuit board can be seen, which optimises microcurrent, as well as an ultra-low-resistance FPC and a unique cavity connection design, which improve the transmission rate more efficiently. The oval nozzle remains, as does the use of the same cable and tip set as its big brother, which is to be welcomed in today’s tight price range. Finally and to the delight of the users, the OH2 can be chosen from 5 colours. But these and other details will be developed in the following sections.





  • Driver Type: Dynamic driver with deposited nano-carbon diaphragm
  • Frequency Response: 20-20kHz
  • Sensitivity: 100dB/mW
  • Impedance: 32Ω
  • Jack Connector: 3.5mm
  • Capsule Connection Type: MMCX





Ikko has gone for a fresher and more eye-catching presentation, including a girl with a more occidental and urban style. Again, an image of a woman on the packaging of an earphone. Is it to attract attention or are these IEMS for girls? Well, you know I’m against using a female image as an advertisement in a mostly male hobby. The urban girl image itself comes as a magnetic figure, which can be stuck on the fridge. I gave it to my niece, who is still alien to this kind of symbolism […].
Going back to the packaging, it came wrapped in a plastic bag. It has an almost white decorated cardboard, which only covers two thirds of the packaging. On that part is almost all the information concerning the IEMS: the brand logo on the top left, on the right the name of the model, in the middle a description and other characteristics on the bottom right. As if floating, there are two holes in the cardboard, which reveal the shape of the outer face of the IEMS: they are both holographic sandblasted, which start from a grey colour and can take on all the colours of the rainbow. The left edge of this cardboard is die-cut to show the urban girl and above it is the magnetic figure. On the back is the complete name of the IEMS, characteristics, frequency response, a realistic photo of the capsules and the brand name. After removing the cardboard, an eye-catching cover divided into colourful boxes with different motifs is visible. In gold lettering, OPAL stands out. She must be sensitive to high notes… There are some more descriptions at the bottom of this side.
The dimensions of the box are 202x139x49mm.
Inside the box, the IEMS are encased in a dense, white foam rubber. Attached to the nozzles are transparent tabs with the brand logo. There is also a classic pin with a black background and gold highlighting with the brand logo. Below this first level are the rest of the accessories. In a nutshell:


  • OH2 capsules.
  • 6 pairs of specially designed Ikko silicone tips in different sizes.
  • 3 pairs of Ikko i-Planet foam tips.
  • 1 MMCX cable.
  • 1 clear brown leather bag.
  • 1 pair of tweezers to remove the filters from the nozzles of the capsules (inside the leather bag).
  • 2 filters for the capsule nozzles (inside the leather bag).
  • 1 warranty card.


The content is practically the same as its big brother OH1s, the same cable, the same leather bag, the same tips… It’s good that they have included the same level of accessories, but I still think that the oval mouthpiece is questionable, as well as the oval tips, even the cable is slightly stiff and I don’t like the MMCX connection.



Construction and Design


Ikko has iterated the shape of the OH1s in these new OH2s, simplifying the design slightly, but without losing beauty or ergonomics. In the lookalikes, the capsule of the OH2s is once again in three parts: the inner side is white (in this case) and is metallic, although it doesn’t look like it. Then there is a central part made of transparent polycarbonate, which covers part of the outer face. Finally, the outer face is closed with another metallic portion. On it is the brand logo and a small slot with a grille. The transparent side reveals a beautifully crafted printed circuit board. The gold-plated MMCX connection is also on its edge. The whole of the outer face has a shape very similar to that of the OH1s: an equilateral triangle with very rounded corners. The final size is small/medium. On this occasion, the outer face is not oddly shaped, it is quite smooth except for a protrusion resulting from the MMCX connection. The inner face is smooth and rounded, but the nozzle does not have the projection of the OH1s, so it is not as long. This time, almost the entire inner face is at the same level and when you get to the nozzle, it stretches abruptly along its entire length. On the OH1s, this rise was more gradual and even the nozzles were longer. But the final shape of the nozzles is almost identical: they are oval nozzles, whose grid can be removed with the help of a tool that comes as an accessory. The grid is a black filter, made of plastic/resin, which has visible holes. It is also oval in shape. Finally, there is a hole in the very centre of the inner side.
The cable is the same as the OH1s model, it is thinner and stiffer than you might expect. It is two strands made up of 127μm wires of high-purity monocrystalline copper, with a silver-plated magnetic core. As mentioned, the connection is still MMCX and these connectors are protected by black plastic sleeves, with the channel letter inscribed on them. They have a soft angled shape and the cable coming out of them is protected by a semi-rigid black plastic sheath. The cable covering is transparent and reveals blue and red-tinted strands. Both the pin, the splitter piece and the 3.5mm gold-plated connector sleeve are polished and shiny metal cylinders. The Ikko logo is engraved on the jack connector. There is no choice of balanced connection, which is a negative point for a model of this price, when such a connection is becoming more and more popular. The cable, despite its bombastic description, doesn’t look like much and is very susceptible to being swapped for a balanced cable.
Again, Ikko has made an effort in design, modifying the look, but building on the shape of their previous OH1s. I think they’ve done away with the frills, such as those unhelpful dents, and gone for a more striking design, leaving that beautiful printed circuit board in the air and returning to smooth, soft lines. The nozzle is shorter and perhaps not as steep, but the size and shape are still ideal. It’s true that the cable is still not ideal for my taste, I find it too stiff and I don’t like the MMCX connections, because the cable tends to rotate. Again, the oval nozzle is a risk and the standard tips have complex ergonomics.
Finally, the construction feels light and the ratio between size, build quality, materials used, beauty of design and weight is excellent. Moreover, the result can be even better because this model is available in five different colours: grey, green, gold, purple and silver (white).



Adjustment and Ergonomics


Normally, Ikko is not known for designing long nozzles. In this case they have again reduced the size of the nozzles compared to their previous model OH1s. The angle also seems to have changed slightly. The result is no less ergonomic, but it is clearly aimed at shallow insertion. I find the use of their oval tips totally useless for my morphology and I have to resort to my beloved homemade silicone tips, filled with foam. Luckily, their inner core is wide and they can accommodate the oval nozzle without any problems. With them I get a real seal and a remarkable level of isolation, as well as an excellent fullness of sound.
Again, I think Ikko’s great design is penalised by the boldness of the oval nozzle design and the tips to match. I’m sure they are designed to extract the full potential of the OH2’s sound, but I still think the fit is critical, not straightforward and will not be appropriate for many users. Fortunately, it is not difficult to find other suitable tips and even in the same accessories there are others that may work better, either foam or silicone, with a more traditional shape.







The profile is balanced/neutral but with a clear mid-centric, warm character. Unlike its big brother, whose graph it shares from low to mid-high, the OH2s have a recession in this upper zone, which detracts from the overall sense of brightness, sparkle and clarity, offering greater control and a more typical, reserved tuning.





If there is one thing that seems to have changed (in me or in the new dynamic drivers) it is the representation of the low end. In no case could one say that the OH2s are powerful in this range. But neither could you say that their bass is anaemic. And this is the difference. In the past, in order to achieve neutral and balanced IEMS, the presence of the lower range had to be unloaded a lot. Now, it is not so necessary, unless you are looking for such a tuning.
The OH2, in my opinion, have a pleasing combination of neutrality, balance and a hint of punch, which is achieved by a very subtle curve, which goes into the mid-range. However, it is also true that the greatest weight is in the mid-bass, with the sub-bass being lighter and less represented. The result is a range that is soft for the development of electronic music or any music that demands a greater presence of the low end, but that has a realistic colour for the rest of the musical styles. I insist, it is a light bass, but not anaemic. It will never overpower the rest of the frequencies, nor will it be left behind, because it is very fast and has a quick decay, but it will always have more than a testimonial presence. It is also true that the result is not very deep, the punch is limited and there is no bass flooding in the music. The texture does not have a rough roughness, but it becomes distinctly perceptible and pleasant. In contrast, the colour feels quite real, as does the timbre. In the low-frequency pure frequency test, the tones appear natural, not very coloured. This means that there is no forced bass tuning and despite its restraint, its development appears natural.
The result is a well-balanced, neutral, light, fairly represented, not outstanding in presence.
On a technical level, it can be described as audiophile-grade bass, effective, very well articulated, dynamic, defined, coherent, its speed is clear, its development is clean, detailed and the notes are reproduced with very good definition. But as a bass lover, I find that the bass lacks punch, more depth, more presence, a little more darkness and a greater ability to create punchier bass lines, as well as a richer representation of its planes. In reality, all this is intuited, because the driver is not lacking in qualities (and with that I return to the beginning of the description, knowing that Ikko is a good expert in these arts), but it gives the feeling that it remains on the threshold of a door to a higher power.





When the lower end is lightened and the treble is softened, it is the mid-range that should remain. And there is no doubt that this is the case. The mid-range of the Ikko OH2 is designed to be enjoyed, even at high volumes. And that is something that is appreciated with styles such as rock or pop, as well as all other musical styles where mid-range representation is paramount. Firstly, that the midrange makes the lower range very good, and it is here that the kick drums, drums, bass guitars and bass guitars all have a presence that is fully justified and adjusted to enrich the mids. The warmth is there, but never as a darkness, but rather as a shading of the treble. The bass tuning does not bring warmth towards the midrange, but is effectively tuned to bring a full body, never sounding overdone, muddy, unnatural or even dense. Thus, in the first half of the central range, a natural, complex, full, but in a good way, rich and quite pure body prevails. It is very pleasant to note that there is no darkness, no heaviness, not a hint of nasal or metallic sound. In this sense the OH2 repeat the tuning of the OH1s, making it canon. Although, it is true that other brands have also sought a similar tuning, as you will see in the comparisons.
The result is an enhanced central band but in quality, it is not an exaltation of presence, it is not about enhanced voices, close above the rest. It is a successful integration of means that enjoy mutual respect in their entirety, where both male and female voices enjoy a shared protagonism, also with the rest of the instruments. There is no favourable treatment of any particular element, but rather the range is choral, in which all the components have their space and are treated with respect and naturalness. It is clear that this is not a brilliant sound and the harmonics of this range are dry and not very extensive, there is no flash or sparkle, not even when it would be desirable. In this sense, the representation is sparse, perhaps the negative point of this zone. Or maybe it’s a blessing, because if someone is looking for IEMS that will allow them to enjoy bad recordings, shrill highs or simply a nice, musical midrange, just pick up a pair of Ikko OH2 and you’ll know what I’m talking about. It’s an analogue sound, harmonious but dynamic, vivid, smooth, but with good definition. There’s no trace of sibilance, but it’s not a dark sound either, nor is it completely nuanced. While I do miss some brightness, a little more sparkle, a little more micro nuance, the sound is sweet and silky, with a good level of detail, though without being scrupulous. Compared to its big brother OH1s, the subtraction of the BA driver is felt and noticed in presence, but also in its more analogue and permissive character. The detail is more rounded, the darkness is not as pronounced, the clarity is not as perceptible and the transparency is warm. Undoubtedly, this is a good alternative for long listening enjoyment.





The difference, in this case, with respect to the OH1s and those other brands that have similarly tuned IEMS, both in bass and midrange, is in the treble. The OH2s are that sweet friend that accompanies you and never ruins your evening. The treble is restful, delicate, unobtrusive, controlled, but pleasant. They have a subtle initial sparkle and the classic valley that attenuates its presence. The result is an upper zone that is also light in presence, which seeks a respectful, insinuating, suggestive presentation, beyond a superior and remarkable emphasis. In this sense, the integration of the treble as a range that enriches the midrange is obvious. The high range is the contribution of quietness and detail to the central area and not a particular protagonism. However, the price to pay is a limited extension, as well as a moderate, even sparse, airy feel, as if it were an almost tube-like sound, rounded at the top end. I understand that this tuning is intended as an alternative, intelligent and focused on an audience that can be quite wide.



Soundstage, Separation


The sense of spaciousness is moderate. Its width is simply good, it has a limited depth and an average height. The perception of three-dimensionality is not very great, although no congestion is visible. The soft character and its slight analytical capacity have a binding effect on the elements. Although the separation is noticeable, the silence, the dark background and the level of transparency are more difficult to notice. But I cannot deny that the OH2 have a clean, pure and diaphanous sound. To sum up, and to use a cliché, the scene veers towards the intimate side, in which the half-distances are very well represented, nothing sounds too close, nor too far away. But nothing stands out with particular excellence. Nor is the enveloping space of the elements very remarkable. Thus, the recreation of the image is not very complex and the location of the elements, as well as their origin, is not explicit.
The level of detail is quite adequate, even beyond its range, and looks better when the source is of high quality. The micro nuances are not as noticeable and the analogue feel of the whole smoothes its recreation.





TFZ My Love 4


In my opinion, a somewhat revolutionary product in the TFZ catalogue (and I’m not talking about its peculiar appearance and colour) is the My Love 4. In a brand legendary for its bass, this model smoothed out that band, creating a profile with an emphasis on mid-high and treble. While I am not a regular reader of all the forums I frequent, admittedly I have a tendency to read them diagonally, I have not found this model to have caused much of a stir and I don’t think it’s fair.
As for the physical differences, the TFZ’s capsule is larger and stubbier, when you put on the OH2’s you realise their superior level of comfort and ergonomics. The integration of the Ikko’s in my ears is excellent, while the TFZ’s are more bulky, protrude more and have more contact with my ear parts, which in the long run, creates more fatigue. I’m not a big fan of the Ikko cable and I prefer the thickness and the better handling of the TFZ cable to the stiffness of its rival. I also prefer the 2Pin connection.
If you compare the lower range of the two, their level of similarity is surprising. You could say that from the low end down to 2kHz, the two have a very similar frequency response. What emerges from this is that the bass sonority is very similar. You notice that both have a very fast punch, I feel that the mid-bass of the Ikko has a higher emphasis, while the TFZ has a more sub-bass point and depth. The rendering is slightly different, there is a little more colour on the Ikko and a more rubbery feel on the TFZ, despite their greater darkness. Both the power of the hit and the recovery are similar. Although I’m inclined that there is more bass weight in the sound of the Ikko. The gumminess of the TFZs allows the Ikko’s bass to be more concise and precise. Otherwise, there are many analogous parameters in the lower range of both models.
Voices sound fuller and closer in the Ikko, with more body, something more noticeable in the male voices. The TFZs represent them as thinner and lighter, somewhat more distant, as well as more prone to sibilance, as they are brighter. In some situations, the Ikko’s greater softness can be a negative, comparatively speaking, because it limits detail and harmonics. It is clear that the timbre is distinctly different, feeling darker, warmer and less vivid on the Ikko. The TFZs have more sparkle, brightness and brilliance. Both the details and the presentation of the instruments change in register from one model to the other. Those in the lower mid-range are better perceived in the Ikko, while those in the upper mid-range are for the TFZ. Nevertheless, I prefer the closeness and fullness of the Ikko’s midrange, even if it lacks the sparkle of its rival in this case.
The difference in treble is clear: there is more representation, emphasis, extension, extension, travel and presence in the high end of the TFZs. Comparatively speaking, it is clear that the Ikko has a more nuanced, lighter and softer high end, with less sparkle and brilliance.
The greater projection of the high end of the TFZs and their slightly greater depth in the low end increases the sense of openness of the scene in the TFZs, as opposed to a more linear and flat perception of the image in the Ikko. There seems to be more width in the OH2, while the sense of separation and three-dimensionality is slightly higher in the TFZ.



Hidizs MS2


If I had to choose one of last year’s favourite IEMS in this price range, I would definitely choose the Hidizs MS2. In my opinion, Hidizs has created a low/mid-cost premium product, with a neat presentation and quality elements, with special attention to its cable and carrying case. Although the cables are similar, both have two strands, even subtly thinner on the MS2, both the connectors and the handling are better than on the Ikko cable.
Although the shape of the MS2 capsules resembles that of the My Love 4, it is slimmer and more comfortable, and has a better insertion, being deeper than that of the Ikko. However, if I had to choose, I’d still go for the superior ergonomics of the OH2.
Again, it is a war between similar tunings. The frequency response is almost identical between 1kHz and 5kHz, while the similarities from the lower end down to 1kHz are great. Again, the biggest differences are in the high end. Although it is also worth noting those 2-3 dB more in the lower bass. In my opinion, the tuning of the MS2s is a winner. In addition, the fact that it has a very well tuned BA driver adds a higher level of technicality, precision, definition and resolution.
With a lower impedance and clearly higher sensitivity, the Hidizs move with a puff and need very little to shine.
Again, a very similar encounter in the low end. Both are concise, fast and slightly decaying bass. But the Ikko’s are superior in these parameters. The MS2s have more punch and more LFO presence, with a more powerful sub-bass. The Hidizs’ greater power gives them other noticeable characteristics, such as better texture, more depth, meatier bass lines, and a more vivid and dynamic representation of planes.
As I said, the frequency response of the centre range is very similar in the two IEMS, but there is no doubt that the neighbouring ranges play a decisive role in the overall sound. No one can claim that the ranges can be evaluated individually, forgetting the others. In this case, the importance is paramount, as well as other non-representable characteristics. The favour of a more extended and emphasised treble, as well as the greater depth of the bass, brings a richness to the mids of the Hidizs, which is not present in the Ikko. On the one hand, the profusion of detail, nuance and harmonics is greater in the MS2s. In contrast, the OH2s are more sparse and bland. The Hidizs’ level of transparency is also raised and the greater depth stretches the scene, even giving it more height and width. The three-dimensionality is more perceptible and the sound is more ethereal and volatile. In contrast, the Ikko is denser, slightly more full-bodied, more compact and less transparent. Their sound is sweeter, softer and more pleasant. It cannot be said that the sound of the Hidizs is not pleasant, but it is more critical and analytical, which must be taken into account. This implies more separation, a larger space between the elements, a 360° level, a higher degree of resolution and the perception of a blacker background.





I think Ikko has a plan and is executing it to perfection. After the OH1s and their distinctive tuning, much lighter in the bass than the OH1 and OH10 models, they are now going down a similar path, maintaining a very similar level in bass and midrange to their sibling in form, but lighter in the high end. It is clear that this move is calculated with the idea of covering the different musical profiles of the IEMS with quality alternatives. And in this respect the brand deserves a round of applause.
The Ikko OH2 has a measured, balanced and musical profile, very suitable for long listening. It is euphonic, almost analogue, with treble that is totally under control, nice and smooth. Everything about their sound is in keeping with their rounded shape, small size, light weight and excellent ergonomics. The OH2’s sound is in keeping with their exterior, with its transparent parts and smooth surface. And the best thing about them is that they have a particular profile that makes them a very special model. I’m sure many fans are looking for something like the OH2 and don’t know it.



Sources Used During the Analysis


  • ACMEE MF02s.
  • ACMEE Magic Sound 4.
  • Zishan Z4.
  • Hidizs S9 Pro.
  • Tempotec Sonata E35.
  • Earmen Sparrow.
  • E1DA #9038D.
  • HiBy R3 Pro.
  • Burson Audio Playmate.
  • S.M.S.L Sanskrit 10th MKII + iFi ZEN CAN.