Moondrop SSR Review

Jul 11 · 6 min read
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The Moondrop Super Spaceship Reference (SSR) is an in-ear monitor (IEM) using a beryllium-coated dome diaphragm dynamic driver. The SSR retails for $40 at Shenzhen Audio. I received the Moondrop SSR from Shenzhen Audio in exchange for a fair and objective review.


I have used the Moondrop SSR with the following sources:

I have tested these headphones with local FLAC and Spotify Premium. Visit my page to get an idea of what I listen to.


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The Moondrop SSR comes in a square white box illustrated with the infamous Moondrop anime waifu in full color. Technical specifications for the SSR are provided in English and Chinese on the back of the box. The package includes a detachable 2-pin cable, three silicone eartips (small, medium, large), a synthetic fabric drawstring bag, a contact card written almost exclusively in Chinese, and a user manual, also written almost exclusively in Chinese. For the price, I can’t complain about the accessory selection. However, I encourage Moondrop to include at least one pair of their MIS foam eartips in future products.


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The Moondrop SSR has low-profile aluminum housings with a glossy clear coat. The faceplates have a black nut set into the surface, and there are several vents on the inner face of the housing and on the side of the nozzle. “L” and “R” are inscribed into the inner faces of the housings. The 2-pin connections are slightly recessed. The nozzles do not have a lip to secure eartips.

The 2-pin cable has a transparent plastic sheath. The Y-split is a black plastic disc embossed with the Moondrop logo, and the L-shaped 3.5mm jack hardware is clear rubber. There is strain relief only above the jack and there is no chin slider. There is a red O-ring on the right-side cable in addition to the typical raised “L/R” indicators. The cable has pre-formed rubber ear guides. The fit of the 2-pin connectors is extremely tight.


The Moondrop SSR is intended to be worn cable-up only. The earpieces have a moderate to deep insertion depth but are comfortable to wear for extended periods. When worn, the entire housing falls below the outer surface of my ear, making the SSR ideal for use while sleeping. Secureness of fit is excellent, but isolation is average. The SSR does not have driver flex.


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My measurements were conducted with a Dayton iMM-6 microphone using a vinyl tubing coupler and a calibrated USB sound interface. The headphones are driven using my Element, which has an output impedance of no more than 1 ohm. The measurements use a compensation file derived from relating my raw measurements to published measurements from Crinacle and Antdroid. The measurements are presented with 1/24th smoothing. There is a resonant peak at 8k. Measurements above 10k are not reliable.


If one were to evaluate the Moondrop SSR based on the graph above, one could describe it as a Diffuse-neutral IEM with a slight mid-bass emphasis. sound signature with a forward midrange. My subjective experience with the SSR has been different. I perceive much more bass than measured, presumably because of my ear anatomy and the insertion depth I listen to the SSR at. I have small ears and insert the SSR as deeply as possible. Other reviewers with access to measurement rigs have found that blocking the SSR’s vents significantly increases its bass response. My guess is that these vents are mostly blocked when I listen to the SSR. For me, the sub-bass is emphasized over the mid-bass, though there is an ample amount of both. The bass response has excellent speed, articulation, and texture. There is a fair amount of mid-bass bleed, but it serves mostly to give the SSR’s lower-midrange body rather than creating sonic mud. The SSR has surprisingly great resolution throughout its frequency response.

Reviews of the SSR have been mixed in large part because of its polarizing midrange emphasis. I used the Moondrop SSR exclusively with Moondrop’s MIS tips, which bring the upper-midrange even further forward than the measurement above indicates. Male vocals are significantly less prominent than female vocals, though vocal intelligibility for both male and female vocals is excellent most of the time. The quality of the imaging and instrument separation is such that instrumentation panned to the left and right is easily distinguished from centered vocals despite the forward upper-midrange. The shouty quality of male vocals is most noticeable with vocal harmonies and gang vocals that are panned to the sides and overlap with instrumentation. Male vocal intelligibility suffers when this occurs. Female vocals have a breathy, mild sibilance to them but are not shrill to my ears. Harsh male vocals have good bite. Timbre is realistic if slightly dry.

The upper end of the SSR’s frequency response is weighted towards a gentle lower-treble emphasis, with limited upper-treble extension. There is a fair amount of sparkle but little air. Transients are not splashy or overly diffuse but also not unrealistically quick in their attack. Soundstage is expansive for a single dynamic driver IEM.


I am a huge fan of Toranku’s target curve, which elevates the Moondrop S8 to a new level of clarity and does wonders for the KB EAR Diamond’s overemphasized upper midrange. However, equalizing the Moondrop SSR to this curve resulted in a subjectively overwhelming sub-bass response. I also did not find the equalized midrange response to be a clear improvement over the raw response.


The Moondrop SSR is surprisingly demanding in terms of its amplification needs and requires a competent dongle or dedicated amplifier to achieve volume levels I find acceptable. The UAPP workaround may be necessary for Apple dongle users. I did not notice hiss with any of my sources.


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The Moondrop SSR stands apart from most IEMs at its price point because it is clear just from looking at its frequency response that its tuners had a specific target in mind for it, as opposed to shoving a mishmash of drivers into a shell and pushing it onto the market. That target may not be to everyone’s taste, but some measure of intentionality counts for a lot. The Kinera Tyr is one of the few competing IEMs that I feel deserves to be in the same conversation as the SSR because it too measures and sounds as though effort and care were taken to make it sound like something. If one is sensitive to upper-midrange “shout” the SSR should be avoided. If not, the SSR is a surprisingly technical monitor that is well worth its price.

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