Hifiman Sundara Closed

Sundara Closed – a new release from the HiFiMan raised many questions. Join me on a quest to answer them all. Let's dive in and see if the Sundara Closed is THE headphone to get at $399.


Sundara Closed – a new release from the HiFiMan raised many questions. Join me on a quest to answer them all. Let’s dive in and see if it is worth the noise around it.

Sundara Closed was a huge announcement. HiFiMan is one of the leaders in the headphone market, no wonder why everybody got excited when the first information started pouring in. I was lucky to meet the HiFiMan crew at CanJam in London this year. If you ever have any chance, take your time to talk to them. They are amazing people, very passionate about audio. Also, very chill and down-to-earth. Remember, kids, audio shows are as much about people as they are about gear.

One of the many cool toys they had was the new Sundaras, and I didn’t hesitate to try them on. After a brief listen, I knew that it was a solid headphone (ups, spoiler). They even proposed that I take a pair immediately so they “won’t have to pack all of that again” LOL. Sadly, I couldn’t take them with me at the time, but long story short, they have arrived in my hands. 

Packaging and Comfort

This is the coolest packaging I have seen. It’s super intelligent. Inside a normal-looking box is a filler made of closed-cell foam. But here’s the kicker: the bottom part of the filler works as a stand for the headphones! With the HiFiMan logo and a plastic base for stability, it’s a proud part of my wall of happiness. How thoughtful and efficient is that? I love it, especially since it is done in a relatively not expensive product.

The rest is pretty much standard. The first impression: a solid piece of headphones, on a heavier side (432g). The whole thing uses a leather strap to place pressure on the user’s head equally. The clamping force is medium, and the entire thing is comfortable for extended periods, but that will depend on the person due to the weight. 

Build Quality and Tech

At first, Sundara C. looks like a classic Sunara with wooden cups strapped on. The headband is mainly made out of metal with some plastic pieces. The headrest is a leather-like material that can move freely with your head.

I only want to see the adjustable angle of the cups, which is available even in cheaper HE400se. That would be a level-up in comfort, especially with a heavy pair of headphones like these. A new part, wooden cups are machined od of a solid piece. Wood is well known for its acoustic properties, but what amazes me is that they were able to secure a consistent, high-quality source of wood for such an incredible production scale. I wouldn’t think it’d be possible if you had asked me half a year ago.

While the headband and the base of each earpiece come from the older brother, the driver is very different. Underneath the earpads, we see a set of acoustic filters: a distancing foam, semi-transparent cloth, and a star-like filter on the driver. Their purpose is to tune and smoothen out the Sundara’s frequency response. The driver features HiFiMan’s proprietary tech, namely stealth magnets, and NEO Supernano diaphragm. It has double-sided magnets, which provide the extra drive required to perform in a closed-box headphone.

Also, that gives them higher sensitivity than the OG (Original Gangsta) Sundara: 98dB vs 94dB. The impedance is lower at 20 Ohms compared to 37 in OG Sundara. Don’t expect to drive them with your smartphone. Like all planars, they like juice, and 20 Ohms is low. Pads are made with synthetic leather and have perforations on the inside, aiding in tuning the headphone.


From all the HiFiMan’s that I have recently listened to, I think I like the Sundara C. the best. The newest release from HiFiMan has a darker tuning that goes very well with my clean, linear setup. Matter of fact is that I like a little darker tuning, so there is my bias. Everybody has one. If they say they don’t, they are lying. It’s important to understand that and differentiate a good product from a product I like.

Back to the topic at hand. The Sundara C. sounds very good straight out of the box. Burn-in didn’t change much, but I did it as usual. Custom Cans @ YouTube measured them before and after burning in, and the difference was pretty small (shout out!). When you make darker-sounding headphones, you need to introduce a sparkle somewhere. Otherwise, they will sound dull and boring.

HiFiMan decided to insert a peak in the lower midrange. It gives a nice brightness like pickled cabbage helps out a fatty, breaded pork chop. Just a cutlet will be super heavy to eat, but crunchy, sour cabbage cut’s through the richness and brings balance to the dish. Exact same situation here. The tuning is dark, but there is not much warmth to it. It still is the HiFiMan, after all. One of the first impressions I have shared with “The Boys”, I mean the staff at Ear-Fidelity, was: “it sounds like a closed HiFiMan should”. As a manufacturer, they have their sound profile. The Sundara C. fits under it, although it has a slight deviation. The core is here intact: the resolution, speed, and control are exemplary.

This is a very resolving headphone (but not as much as Sundara OG). A closed can is a compromise trading sound staging for bass extension. The space is close but not confined. Shrank in size, but not bound to your head, which I hate with a burning passion. For a closed headphone, it’s decent, I heard better, but they were much more expensive. The most important thing is that it can create a convincing illusion of being there. The resolution is very good. Thanks to careful tuning, the extended bass doesn’t influence the amount of detail retrieved from the source material. This is one of my absolute favorite combinations: punch and resolution.



Let’s start with one of the most over and simultaneously underrated artists of generation Z: Billie Eilish. My Strange Addiction has a mysterious, toned-down character with powerful bass. I can recall clearly that at release, people were throwing turds around the mastering. The fun part is that the album is mastered very nicely. Most home audio systems just can’t handle this amount of bass, and even some headphones struggle with that. Worry not, my friends, because Sundara C. lives for tracks like that. The bass is entirely flat for the lowest lows of hell. It’s utterly uniform in character, meaning that the driver is working effortlessly throughout the whole range. The next thing that catches your attention is the resolution and speed. The electronic bass notes are presented with zero coloration. If you like EDM, you’ll be thrilled. As long as your amp can handle it, nothing can stop Sundara C. What about non-electronic instruments? Riders on the storm by Doors has a simple yet catchy bass line that often gets overpowered by other instruments. Sundara C. can deliver separation between ranges that allows you to easily pick up the bass lines even when a lot is happening at once. The bass sound natural and has a very pleasant timbre to it. There is nothing wrong I can say about this bass. Unless you want an elevated bass response or added warmth, there is no reason not to choose this headphone.


Bass is not the whole picture. How about the mids? One of my test albums for voices is Korn Unplugged. Especially the cover of Make me bad/In between days when Jonathan Davis sang with Robert Smith from the Cure. The contrast between the aggressive, nasal voice of Davis and the smooth, clean voice of Smith is something else. The Sundara C. catches that perfectly, delivering the emotional impact of the song. The timbre of the midrange is clean. There is a slight edge added to the vocals, primarily male. An accent boosts this relatively narrow band. To be frank, I like it, and I wouldn’t want it to be flat. The midrange gains some life thanks to that, and without it, I think it would be a little flat. Just the right amount of bonus energy fixes that. With female voices like Dusty Springfield’s classic Son of a preacher man, there is a tiny bit of sibilance at the top of her range. It pops up occasionally, but I wouldn’t call it a deal breaker. As previously mentioned, it brings a sparkle of life to the sound. If we are talking string instruments, there is no way not to mention Carlos Santana. I might come up as ignorant here, but I have a soft spot for tracks like Smooth and Maria, Maria. That was what I was listening to when I was a kid. It’s possible I was picking up girls at school dances to those songs, but that’s not confirmed. In the latter song, there is this fantastic, simple riff; I’m sure you know which one. The master’s guitar sounds sharp and crisp. It really brings all the boys to the yard. Wrong song reference, my bad. To sum it up. There is a spark of life in the midrange that can cause some sibilance in extreme situations. Overall the tone is neutral, and there is a lot of detail and textures. Definitely holds its own against the competition.


I think you already know. The treble is rolled off, and it shows—the darker tuning forces that. The treble plays a secondary role, supporting the other ranges. What they lack in volume, they hold in quality. What we get is very good indeed. In Michael Jackson’s Billie Jean (I know, I’m not too fancy today with music selection. Beat It…) the sound of cymbals and violin is a little smoothened out but still rich with information and textures. In the Cantina Band from Star Wars New Hope, you can enjoy many cymbals and other high-pitched instruments. Enjoy is a word I have chosen specifically. This song can get overwhelming in a brightly-tuned system, but here you are perfectly safe. It’s hard for me to explain that because they still preserve their sparkle while being laid back. The instruments sound very natural, with the right timbre and natural decay. It’s a nicely tuned natural range that is a great addition to the overall tuning. The dark presentation doesn’t have to mean bad treble, and HiFiMan proves that with the Sundara C.


Soundstaging of these headphones is something special. Many people accuse closed-back headphones of completely destroying the sense of space. Let us be honest with ourselves. We have heard that time and time again. Remember when I told you that it sounds like a “closed-back HiFiMans”? It also applies to the soundstage. Think of Sundara OG, but shrunk down. You might not even catch that when you listen to simpler mixes. Think of EDM, for example. But when you go into more complex music, you start to notice the sound is bound between your head and the wooden cups. When you listen to Snuff by Slipknot, you can feel a very good separation between instruments, panning, and overall order. Everything has its place, and it’s easy to “find”. In a composition with a big soundstage but a small number of instruments, you can hear the natural reverberation of the recording. The wooden cups might slightly amplify it compared to the super clean Sundara OG. For example, you can take any overplayed, overhyped, and overengineered tracks from the Stockfish label. I’m not mean. I love Stockfish. You can buy one album from them, and that’s it. They all sound the same. Back to the topic at hand. They emphasize vocals making them super powerful, in the center of the events. The Sundara Closed can replay that with no issue, with all of the reverb behind them and the few instruments that are used. Being contained in a small space, the “stockfish effect” gets even slightly amplified. To sum it up, Sundara Closed offers one of the nicest soundstages I have heard in closed headphones, especially at this price range.


JDS Labs Element III

My daily driver now is the newest Element III from JDS Labs (review coming soon). It features a single-ended output which drives Sundara C. very well. Together they deliver a detail-rich, powerful sound that sits on a pitch-black background. Looking at current pricing, it suits Sundara C. nicely in this too. This type of sound fits EDM, metal, rock, and other intense music genres. This is a set for you if you want absolute control over the sound.

Hifiman EF400

The HiFiMan’s DAC/AMP took the world by storm. No wonder why reasonably priced R2R DAC with a powerful and clean amplifier can get you really far. Combining that with Sundara C. brings them to another level. There is much more breath, a much more natural tone. The Element III sounds strained and nervous in comparison, but it has more impact in the low bass. It’s definitely an upgrade over the Element III, but this amp is in another price range. Using a balanced connection as always helps, but in this case, less than usual. That might be due to how powerful, and capable this amp is even in SE. This indicates that Sundara C. has the ability to become secondary headphones for a higher-quality main setup. 


Hifiman Sundara

And the question we all want to be answered. How does it stack to the OG Sundara, and is it worth the extra cash? I like the closed version better. OG Sundara is a brighter-sounding headphone with a more neutral characteristic. It’s also cleaner sounding. The sound stage of the open version is superior. It is one of the best bang for a buck you can get on the market. The characteristic of the OG is flatter and smoother. But on my system, it sounded a little too lean for my taste. 


There is just no comparison. Everything OG Sundara does, the closed does better. Thanks to reasonable tuning, the bass of the closed version isn’t tiring and overpowering, which could be a point for the OG.


Here it gets interesting. I have mentioned the peak in closed Sundara, which might cause some sibilance. The OG doesn’t have that, providing a perfectly smooth response and vocals. Open-back construction gives more breath between the notes and words sung. The OG might be a nicer choice if your focus is on acoustic instruments or vocals. 


OG Sundara has much more to offer in this range. The treble is extended in comparison and has a nicer edge. The attack is faster and crisper. The cymbals sound much more natural, having a more natural, not smoothed timbre. Overall, the Sundara Closed would suit people who prefer a safe approach to the timbre. 

Overall, both headphones score very high on my list. Sundara Closed costs more, but for me, the investment is worth it since it fits my taste better. It’s a great product, but I believe the OG Sundara is a better bang for a buck. Not by a lot, though. It comes down to your preference: Acoustic, jazz, light rock, voices – OG Sundara. EDM, metal, punk – Sundara Closed.


Hifiman HE-400SE

This is a very interesting case. The quality-to-price ratio of the HE400se is crazy high. Is the Sundara C. able to even close the gap? At first, I listened to the HE400se. There is nothing wrong with it, really. But Sundara C. really showed me how much I was missing. The resolution, engagement, and overall quality jump were incredible. Interestingly, the soundstage of the Sundara C. was not much smaller but more precise and separated. That’s impressive for closed-back headphones. The overall smooth sound of HE400se was masking detail compared to the star of this review.


The He400se has a full bass for an open-back headphone (fuller than the OG Sundara). It’s warmer and rounder than the Sundara Closed. As mentioned before the Sundara C.’s bass blows everything else in its class, so yeah. There is that.


The HE400se is much smoother and more forgiving than the Sundara C. It’s much safer for users who listen to music of various recording qualities. That said, the detail and resolution of the Sundara C. are addicting. Hard to go back.


The HE400se has a much more pronounced treble and is a much brighter-sounding headphone. It elevates the cymbals and other high-pitched instruments, giving them the space to shine. The Sundara C. holds its own in quality, believing it’s better than quantity. 

Sundara Closed is a much better headphone than the HE400se. More than I expected it to be, fully justifying the price difference. Both are excellent choices in their price range, and when it comes to sound HE400se is safer, while the Sundara C. is better.


TL:DR – it’s awesome. Thank you for joining my TED talk. 

Sundara Closed is a brother (sister?) of the well-known Sundara open back. Just that is a lot of pressure. I’m happy that it exceeded my expectations hitting my taste just right. Despite the price bump, it is an excellent deal. It features all of the newest bells and whistles from HiFiMan, including stealth magnets and NEO Supernano diaphragm. The headphone itself is a new design using parts of Sundara’s chassis but with a brand new driver. While the looks are… controversial, the sound isn’t.

It has a very pleasant dark tuning with rolled-off treble and bass that is flat to 20Hz. Rolled-off treble doesn’t mean a flat sound. Incredible bass and exciting mids provide drive and fun. The treble holds its own with sufficient detail and crispiness. It’s a dark sound, not a dead one. The sound staging is very good for a closed-back. Music is close but not on top of listeners’ heads. It can even rival some cheaper open-back headphones in this regard. The headphone is not the easiest to drive due to their low impedance. The JDS Labs Element III does that with no problem, but my DAP couldn’t handle them. In the end, the most important thing is that those are awesome headphones, and I had fun doing this review.

Highly Recommended.

Big thanks to HiFiMan for providing us with the Sundara Closed for this review. I wasn’t paid or asked to say anything good or bad about this product, all of the above is just my personal, unbiased opinion. HiFiMan hasn’t seen this review before publishing it.