Rose QuietSea English Review


Clarity Has A Price




Construction and Design




  • Overall, very good sound and representation in all three ranges.
  • Great low end, with very particular bass, deep, dual, dark, rough, attractive and captivating.
  • Very good ability to recreate detail and generate layers.
  • Excellent cable with choice of balanced 4.4mm plug. Very good zipped case. Rose demonstrates that great capsules can be paired with great accessories and options such as various colours and
  • SE and BAL plugs.




  • There is some imbalance in the midrange, between the first half and the second half. A little more homogeneity and smoothness in the upper-midrange would have been superior.
  • MMCX interface.
  • The shape and design generates some discomfort for me over time.
  • Although the cable and the zippered case are excellent, they only come with one set of tips.


Purchase Link


Link to the WEB




Founded in 2015, Rose Technics is an emerging audio brand that has spent years in the pursuit of unparalleled original sound reproduction through intelligent technology and meticulous craftsmanship.
I can’t hide my fondness for this brand and have been lucky enough to review some of their great models, such as the Mini2 MKII 2.0, the QT9 MK2 and QT9 MK2s, as well as the Martini earbuds. And I have to admit that each of them is on my list of favourites in their respective categories. So it’s no wonder that every Rose Technics model that comes on the market gets my attention. That’s why I’m in luck again today, to be able to review their QuietSea model. At first glance, I thought it was a clone of the Ikko OH2 as the capsules are completely identical. However, the brand acknowledges that the QuietSea has been designed in collaboration with IKKO after studying over 7000 ear samples to design a universal shape that is comfortable for the masses. On the other hand, it has also been tuned by professional acoustic engineers with years of experience in this field. It is a joint work of Mr. Xie (acoustic engineer of Rose Technics) and Mr. GaoQiao (ex-Tokio Audio). Together they have fine-tuned the tuning of the pair to create an effortless sound with dynamic resolution and rich tonality. The pair has been tuned to deliver a quality sound for multiple musical genres.
Internally, the QuietSea is a new model that uses a unique CNC-machined zinc alloy dual-chamber dynamic driver. It uses a special gold-plated brass dual-chambered dynamic driver with a topological diaphragm that produces a clear sound with ultra-low distortion. The pair is supplied with a high-purity four-strand monocrystalline copper wire. It also uses a powerful magnetic design: the transducer parameters are constantly adjusted and optimised so that the pair has a controlled airflow and produces a more accurate and lively sound. The pair achieves a magnetic flux of more than 1.5T, which also aids in easy handling.
RoseTechnics Quiet Sea IEMs come with a premium quality cable as standard. This is a high-purity four-strand monocrystalline copper cable made from premium OCC 5N wire cores. This cable has a standard 3.5mm connector option and is also available in a 4.4mm balanced version.
After this comprehensive introduction from the brand, let’s take a look at what the Rose QuietSea really looks like, in my view of course.





  • Driver Type: Dual chamber dynamic with 10mm topological diaphragm.
  • Frequency Response: 20Hz – 20kHz.
  • Sensitivity: 99dB.
  • Impedance: 32Ω.
  • Harmonic Distortion Ratio: less than 0.1%.
  • Jack Connector: Choice of SE 3.5mm or BAL 4.4mm.
  • Capsule Connection Type: MMCX
  • Cable Length: 120cm.
  • Weight: 20g.





The Rose QuietSea comes in a medium-sized black box, whose dimensions are 195x145x52mm. On the front side you can barely see anything: Chinese lettering inscribed in the centre and wavy lines moving across the diagonal of the box. On the back, at the top are the product specifications. Underneath are the brand’s contact details, in the centre the name of the model and below that the logos of the certifications it complies with. There is also a sticker with the colour and cable connection. In my case it is the Silver version with 4.4mm cable. After removing the outer cardboard, a matte black box with the same Chinese lettering in the middle appears. The box opens like a chest and the first thing you see is a sheet of onion paper with the capsule exploded view. Underneath is a large foam mould that protects the two capsules and the grey zippered case. Underneath is a user’s manual and inside the case are the rest of the items. In summary, the complete contents are as follows:


  • The two Rose QuietSea capsules.
  • A four-strand coiled textile-coated cable with 4.4mm connector.
  • One zippered case.
  • Three pairs of white silicone tips.
  • One tool for removing the MMCX connectors.
  • One user manual.


It is clear that this is a very high quality set of capsules, cable and case. It is very difficult to find a cable as good as the one that comes standard with these Rose QuietSea. I insist that I don’t like the MMCX connection and I must confess that this connection fails me in the previous QT9 MK2 and QT9 MK2s models and that prevents me from enjoying them with total freedom. On the other hand, it is also worth mentioning that the zippered case is excellent for the price, both in finish and size, as it is able to hold the whole set with ease and has a zip that slides smoothly.



Construction and Design


It is clear that this is a capsule design that has already been seen in the Ikko OH2. The capsule of the QuietSea is divided into three parts: the inner side is grey (in this case) and is metallic, although it doesn’t look like it. Then there is a central part made of transparent, dark polycarbonate, which covers part of the outer face. Finally, the outer face is closed with another metallic portion. On it is the model name and logo, as well as a small slot. The transparent side allows you to see some of the cables inside. On its edge is also the gold-plated MMCX connection. Next to it is a letter indicating the channel. The whole external face has a shape very similar to an equilateral triangle with very rounded corners. The final size is small/medium. The outer face has no strange shape, it is quite smooth except for a protrusion resulting from the MMCX connection. The inner face is smooth and rounded and the mouthpiece does not have a very elongated projection. Almost the entire inner face is at the same level and when the mouthpiece is reached, it stretches abruptly along its entire length. These nozzles are oval and have a perforated metal grid. Finally, there is a hole in the very centre of the inner face.
As for the cable, it is possibly the best cable that can be found as standard in this price range. It is a 4-strand coiled cable protected by a grey textile layer. It uses a high purity monocrystalline copper conductor made from premium OCC 5N wire cores. This cable has a standard 3.5mm jack option and can also be chosen in a balanced 4.4mm version. The jack connector sleeve is a smooth metal cylinder. The 4.4mm BAL connector is gold plated. The cable outlet is protected by a transparent plastic sleeve. The splitter has a hexagonal metal sleeve with the brand logo inscribed in the centre as well as the brand name. Inside is a black plastic piece that imprisons the cables. The back is an oval metal piece that has the same surface as the rest of the pieces. Inside there is another black plastic piece in the shape of an 8 that holds the cable tightly. The cable has semi-rigid transparent plastic ear guides. The sleeves of the MMCX connectors are two smooth metal cylinders, with the same shape and surface as the other parts of the cable. The MMCX connectors are gold plated.
A design shared with Ikko, with a very suitable shape that has oval nozzles. The cable is of very high quality. But it has MMCX connections, something that may ruin my experience with this model over time, as it has happened with the previous QT9 MK2 and QT9 MK2s. A pity.



Adjustment and Ergonomics


Although it may not look like it, the opaque parts of the capsule are metallic. The size of the capsule is medium to small. The mouthpieces are short and oval in shape. They have a particular angle. The result is ergonomic but clearly aimed at a superficial insertion. In this case there are no oval tips as in the Ikko model. However, they were not suitable for my morphology. Neither are the standard tips and I had to resort to my home-made large foam-filled tips. As they have a large inner core, they fit easily into the oval mouthpieces.
As I said at the time, I think the great design of the Ikko/Rose feels penalised by the boldness of their oval mouthpiece design. I maintain the impression that its fit is critical, not straightforward and will not be appropriate for many users. Fortunately, it is not difficult to find other suitable tips, either foam or silicone, with a more traditional shape, on the aftermarket.
All in all, the ergonomics might seem exceptional due to the small size of the capsules and their relatively flat design. But when it comes down to it, the shallow fit and the oval mouthpieces mean that over time I feel that the shape is not the most suitable for my ear canal, causing me some discomfort and fatigue. And that’s a pity because the fit and integration of the capsules in my ear is very good.







There is a certain similarity in the frequency response of the QuietSea to the Harman 2019 target. It is possible that it has a softer bass and that the double peak in the midrange and early treble is more pronounced. There is arguably a more pronounced W trend in those high end peaks. But there is also a clear extension in the treble area. In this way, the profile is slightly oriented towards brightness and light, something that is obviously noticeable in that W that exists in the 2khz, 5khz and between 8 and 10kHz. Honestly, I would have liked those peaks to be smoother and the lower sub-bass end to be higher. But this is not my tuning, but a collaboration between Mr. Xie (Rose Technics acoustic engineer) and Mr. GaoQiao (ex-Tokio Audio).
Actually, it is not a completely unique tuning, as you can see several models moving very close to their frequency response.





The low end is relatively neutral, for a bass lover like me. It is clear that I would have raised the sub-bass end, leaving the rest of the lower range in the same way. However, I have to admit that the bass has quite a bit of personality and is more than noticeable. First, because of their sonority. The QuietSea have a dual, dark behaviour in this area, something that differentiates them from the rest of the IEMS and gives them a greater sense of depth and realism. This dark component is apparent in the very low frequency pure tone test. The 20Hz tone reproduction emits a coloured sound vibration accompanied by this dark and relatively sensory sound. This dual perception is not quite normal and I must confess that, despite being slightly unreal, it has a certain attractive and peculiar sonority that makes the QuietSea’s bass quite unique. From 30hz onwards the sense of darkness is mixed with a sound wave of distinctly sensitive power that gives it a sense of superior body, volume and presence. It is possibly this characteristic that gives the bass sound so much personality and a presence above neutrality, as well as its very attractive, yet dark and coloured behaviour. It is not a sensory bass, nor is it the deepest or darkest, but it does have a blend that makes it more expansive, fuller and more voluminous. There are many IEMS that stay in the sub-bass, generating a deep, physical sensation, but they remain relatively low in punch, as does their extension. The QuietSea stretches the sub-bass boundary and joins it with the low-midrange, keeping it fairly horizontal towards the midrange. In this way, the lower range becomes large, noticeable and voluminous. If it lacked control and speed, the result could be disastrous, but the QuietSea shines in both respects. Technically speaking, the bass hits are compact, rounded, fast, with just enough spring to give them realism, but without overdoing it to maintain a compact, concise and tight body. It doesn’t feel dry, but rather juicy, full-bodied and with a sonority that mixes a subtly coloured vibration with a dark and rich aftertaste. It is this behaviour that moves the low end away from neutrality. Although it is not an IEM for bass heads, its behaviour is clearly oriented towards bass lovers due to its particular qualitative characteristics. It is undeniable that there is power, even more than I would interpret by looking at the graph. And that is the result of a lower range that is quite linear, that is not only focused on the bass-midrange, but is able to be present in the whole range.
In the unfiltered, dirty bass reproduction test, the QuietSea’s are able to follow bass lines quite easily, without mixing them up, keeping the bass in check and delimiting them masterfully. They are able to locate them in their zone and do not let them take up more space than necessary and realistic. In this way, the intrusion in the midrange is very low and allows the vocals and other elements to maintain their prominence. It is true that a certain colouring persists in the lower notes, something that can be off-putting for purists. But it is also true that this sense of dual and dark sonority allows to maintain that fragile magnetic and powerful balance that grabs my attention. To all this, and as a result, we must add a texture that is the fruit of this dual reproduction: the vibration and the darkness give rise to a rough mantle that is the culmination of a sound and behaviour that is as particular as it is attractive.





The first part of the midrange carries the existing body and volume of the lower range, but a lower prominence. In this way, the male voices possess physicality, a marked base, with a certain power and volume, although it is placed at a certain distance that prevents them from being more of a protagonist. They lack a point in their extension to be more complete and presential, something that keeps them from having a more exuberant and richer representation. There are times when they feel closer, but they still lack a more constant thrust throughout, as well as a higher power. It’s as if there is a certain hollowness in some phases. The base is very good, with a strong physical, visible and sensory foundation. But, as the voice fills out, a certain bump is perceived, while the higher elements become more prominent. This is how the hissing and wheezing flirt with the permissible limit. It is not a markedly sibilant IEM, but those peaks at 2Khz and 5khz make them more visible than usual in these aspects. Ultimately, the first half of the midrange ends up with that sunkier aspect that prevents a more balanced and fuller range. And that’s coupled with a rapid ascent into the midrange-highs. But somehow the QuietSea manages to maintain some control and retain a more homogeneous sonority than the chart represents in this area. I don’t find the midranges to be deliberately bright, shouty or excited, but rather keep a warm base, supported by that dark air of the bass, which helps it to remain in that natural, somewhat analogue and romantic zone, despite the final brightness of the harmonics. It is true that many elements end with that final sparkle, brilliance and shine, leaving, at times, a space in the middle that does not feel occupied. But it is also true that the weight of the notes is high and their representation is relatively thick. This characteristic moves the QuietSea away from a sharp or analytical sound and places it in that gentler, more homogeneous environment, despite those bright nuances in the higher harmonics. As a result, the female vocals are more prominent, as are the guitars, while the cymbals become more persistent. This is not a brilliant timbre, but its balance is sustained by that mix of darkness, note weight and sparkling nuance.
The QuietSea have quite good clarity and transparency, which contrasts with the darkness and warmth of the low end. In the sum, brightness and light may win out, but the thickness of the notes and the smoothness of their travel also support the result being a more pleasant and musical sound, rather than thin or sharp. And that’s something the sibilance is grateful for, as it would otherwise be more piercing, given that the QuietSea flirts with that hot zone on many occasions.
The end result is an ambivalent, but corrected, zone that can be very pleasant and relatively splashy. It retains a good timbre, a solid base, a somewhat discreet and distant centre point, which contrasts with an excited second half, clear, crisp and present, but rounded in its development, to maintain smoothness and a certain musical homogeneity.





The treble starts from the peak of the midrange-high, energetically speaking. Quickly, the tuning places a control zone to counteract the negative effects of such a rise. That slight drop prevents the first highs from being too sharp or hot. However, Rose has managed to stretch the high end beyond what is usual for a dynamic driver in this price range. This way, the energy level persists and this is felt in our eardrums. The advantage is that the treble is not completely thin, sharp or piercing, but has a subtly rounded edge, which makes it easier to tolerate.
It is clear that the energy level in the midrange and the first two phases of the treble outweigh the power struggle that exists with the low end. Despite this, both the weight of the notes and their thickness and rounded peak, the sound remains below my tolerable limit, maintaining very musical sound characteristics, without losing brightness and sparkle in the higher harmonics. All this gives it an extra richness in the nuances and end points of the elements. As well as a certainly natural, albeit excited, sonority, within the sound channels of a dynamic driver. But there is also a bright undertone, which can be more or less persistent depending on the song or genre of music. This aspect is another factor that can lead to fatigue for the listener who is used to a softer, lighter environment in the high end, not as explicit and exposed as the QuietSea’s treble.
Finally, there is a certain amount of noticeable and pleasant air.



Soundstage, Separation


In my opinion, the QuietSea has a good balance on all three axes, with none being too superior to the other. They are not too wide and have a good level of depth, as well as a moderately good height. This gives them a rather semi-spherical, but frontal representation. The good height perception adds a certain subtly ethereal, three-dimensional effect, but without going over the head. The remarkable lateral impression offers a stereo presence that falls just short of crossing 180 degrees. However, the whole remains attached to the head, at a specific distance. It is not an intimate scene, because it goes beyond and that is something that the depth it generates overcomes this barrier. But it remains in that spherical representation I have already mentioned.
The amount of air, clarity and transparency helps to generate a certain vapour in the scene and to distance the already well-separated elements, thanks to the good technical characteristics of the QuietSea. Even this unforced distancing of the elements is enough to feel an incipient dark background.
Everything seems well placed in this semi-sphere of controlled distances. In this way, the image is discernible and the provenance of the elements is simple and easily located.
I have already mentioned that this is not an analytical sound. But there is a remarkable level of technique that allows a great deal of detail to be visible. It is true that the more excited tuning in the high end makes the high details more perceptible and has a tendency to overshadow small elements in the midrange. But even so, I was surprised by the ability to discern these micro details in a seemingly small area. The layers are not very far apart because of the limited distance, but there is enough air, distance and technical skill to represent those elements. It’s a pity that the weight is heaviest in the treble. But within such a controlled space, the QuietSea are able to reveal a lot of detail without sounding analytical or unnatural. And this is something I didn’t expect in this price range.





Simgot EA500 Black Filter


The simgot EA500 are IEMS that play in a similar price range. While it is true that the Rose cost $90 on their own website, it is easy to find them for $50 in some specialised shops. At this price, it’s a bargain set, almost unbeatable. The Simgot’s cost around $71 at the time of this review and can certainly be a great touchstone for the QuietSea. Starting with the packaging, the EA500 has a large zippered case, as does the Rose, 2 pairs of tuning mouthpieces, which gives it an advantage over the Rose. In terms of accessories it’s very similar, but I’ll take the Rose’s cable, with the 4.4mm BAL connector and that textile cover available to very few as a standard accessory. On the other hand, the EA500’s cable is not bad, silver-plated with two transparent strands with PVC coating and a 3.5mm SE connector with a rather simple plastic sleeve. In terms of capsule construction, the EA500s feature a polished, shiny, mirror-finished design. Its shape is an equilateral triangle with very rounded corners, a stubby body and a two-tiered inner face. In addition, as mentioned, it has two pairs of interchangeable nozzles. These provide a slight change in the midrange and treble. The Black filter excites the tips of the peaks in the second half of the frequency response. This filter has been used for comparison with the QuietSea because of its closer sonic resemblance.
In terms of ergonomics, despite the larger size of the EA500s, they fit very well in my ear canal. At first, the QuietSea seem better in this respect, with the smaller capsule that seems to hide in my ears and fit more flatly. But, as time goes by, they end up producing a discomfort that did not appear at the beginning. This has meant that from a very promising start, I have lost the ergonomic battle against the EA500, even though they are heavier and bigger.
In terms of sound performance and sensitivity, the EA500s are slightly more sensitive, although the difference is subtle.
As you can see from the comparison of the two frequency responses, the QuietSea should be brighter. However, in my opinion the EA500s have a brighter sound, whereas I find the QuietSea warmer. It may be the thickness of the notes. The EA500s are lighter, thinner and more analytical. From the low end, the Simgot are drier, compact, tight, technically good and precise. They have a slicker texture and a great behaviour. The QuietSea’s are slightly more elastic, with a bit more bite, more darkness, a rougher and more pronounced texture, giving a warmer, rounder and deeper feel. I prefer the QuietSea’s slightly dirtier, thicker, darker, deeper and rougher bass. The EA500s are more academic and refined in that respect. And it’s worth noting that the frequency response curve is practically the same, the difference is in that colour, in that more textured surface of the QuietSea and in the technical skill and control of the EA500.
In the midrange, the difference in note weight and finesse persists. The EA500s are thinner, finer, leaner and more defined. There is a slight warmth to the QuietSea’s, which gives vocals a denser, fuller base and a smoother, rounder and subtly closer colour. However, the EA500s seem technically superior, offering cleaner, clearer, more separated and defined midranges. It’s clear that this is a battle between the more relaxed, darker, smoother and rounder sound of the QuietSea, versus the more refined, cleaner, neater, clearer, crisper, cleaner, thinner, leaner, more separated and analytical sound of the EA500. Within such a similar profile, this differential timbre and behaviour can form a great combo to enjoy on a variety of occasions.
The high end of the EA500s is more piercing, crisp and penetrating, due to their thinner, cooler notes. There may be more lift and energy in the QuietSea, but their rounder timbre and note weight make them less sibilant and more restrained in those peaks. There is plenty of extension in both models, and the difference is still in the way the treble is represented in the two models, as well as the subtle differences in energy. Both have great extension for dynamic drivers in this price range, though.
In terms of detail, the EA500s are more explicit and may appear to be much more expressive and informative in this department. But, as is often the case, the macro-detail so present tends to obscure small nuances by overexposure. However, the QuietSea’s maintain a good relationship between macro and micro detail that favours the observation of those fine details, even reaching higher levels than the EA500, depending on where they are located. The Rose’s have more depth and that helps them to generate layers and decipher them better. On the other hand, the sound is more refined, thinner and separated in the EA500s, while their background seems darker and more discernible, as it also treasures a greater sense of resolution and precision.
In terms of scene, the EA500s are airy, separated, with very good width, even height. But the QuietSea’s are a little deeper. Perhaps there’s more of a three-dimensional, open feel to the Simgot, because of that more splashy, dynamic sound, which seems to have more movement, a crisper, more oval exposure. The QuietSea persist in a rounder, more recessed representation at the extremes.





Rose Technics does not disappoint despite using a shared design with Ikko and a frequency response with a couple of somewhat repellent peaks. The Rose QuietSea are excellent IEMS that should be listened to with open ears. The clear example that a graphic does not completely dictate the sound of an IEMS. They come with a spectacular cable, which could be half the price of the set, with the possibility to choose a 4.4mm balanced connection and a case that would have been a dream for higher-priced models. With a price on the brand’s website of $90, but which can be found in specialised shops for $50, they represent an aural kick to the rest of the competition. And not just in terms of design and accessories, but more importantly in terms of sound. With a very distinctive bass that blends darkness and roughness with an engaging and captivating sonority, the QuietSea’s are deep and pleasing in the first half of the frequency range. The early midranges are well grounded, relatively full sounding and possess a warm timbre peppered with energetic treble, but softened at the peaks to control musicality, but without losing sparkle and extension. Very capable at revealing detail, with a great balance in the presentation of micro and macro elements, they also have a good ability to recreate layers of sound and separate them in depth, generating a realistic, semi-spherical and relatively wide scene. Undoubtedly, a very musical model, more balanced and enjoyable than I might have thought at first. If it wasn’t Rose it could be a surprise for me. But, in this case, it’s all about maintaining a very high standard, something that may prove difficult for the competition and also for the brand’s future models. But it only makes me want to test their new models all the more.



Sources Used During the Analysis


  • MUSE HiFi M3 II.
  • Tempotec V3.
  • Hidizs S9 Pro Plus.
  • Burson Audio Playmate II.
  • Aune X8 XVIII Magic DAC + EarMen ST-Amp.