Fit and Comfort

Seen above is the HIFIMAN HE1000 Stealth placed on a mannequin head, to help show how these headphones would look on the human head. Note that the head is slightly under average sized, so account for the discrepancies accordingly. As with all headphones, getting a good fit and seal is crucial, so make sure to properly use the available height adjustability of the headband and the swivel/rotation of the ear cups themselves. This section is mostly a summary of the points expanded upon in more detail on the previous page and I will mention here that the HE1000 Stealth is about average for planar magnetic driver headphones at ~458 g, which is otherwise on the heavier side overall. That said, owing to the larger frame and ear cups, the mass density is not as high as you might think. Secondly, the weight distribution is quite good here courtesy the wide suspension band and I personally had no issues wearing this set for two to three hour sessions anyway—I usually go less than this unless working on reviews and the HE1000 Stealth is among the more comfortable headphones for me thanks to the multiple swivel and pivot options in addition to the roomy and soft ear pads. Clamp force was about perfect for my average-sized head too and, if anything, it's more the size of the ear cups on the side of my head that keeps me self-aware of these than the actual weight and clamp. I do recommend using these in a quiet environment lest others around you get a second-hand listen, or the ambient environment affect your listening experience, and people will certainly gawk at you wearing these in public no matter what you are listening to.

Audio Performance

Audio Hardware

Please read the relevant section on this page for a brief introduction on how planar magnetic drivers work if you unfamiliar with them. To summarize, it involves ultra-thin diaphragms with conductive traces as the effective voice coil. This theoretically allows for lower inertia paired with high magnetic flux fields generated from magnets to move the diaphragm back and forth very quickly for fast transients and increased resolution while lowering distortion. HIFIMAN is using what it calls the nanometer thickness diaphragm, which some have taken to mean a single nanometer thick. I suppose in that regard the marketing has worked, but it's more that the thickness of the diaphragm is under a micron, and thus in the nanometer regime. The stealth part in the name here refers to HIFIMAN's stealth magnet system which debuted with the flagship Susvara in 2017 having the goal of minimizing sound distortion, and has trickled down to the more budget-friendly offerings too. This is not to say that the magnets used here are the same as in, say, the HE400se in terms of field strength and flux, and I am not even sure what the difference in the drivers is here compared to the HE1000se since both claim the use of stealth magnets as well as the nanometer diaphragm. This even weighs more than the HE1000se so it's not like there is a single-sided magnet implementation here vs. dual there. Then we get to the "Window Shade" system on the outside to better retain the open-back nature of the HE1000 Stealth while minimizing sound wave reflection and refraction. All this comes together to make for a premium set of headphones with a rated sensitivity of 93 dB/mW and a rated impedance of 32 Ω—not the hardest headphones to drive but will still necessitate a decent amplifier to get loud. You don't need to go too expensive here though and I recommend a solid state source with good current output.

Frequency Response Measurement and Listening

I will mention that I have a general preference for a warm-neutral signature emphasizing a slightly elevated bass and smooth treble range with detailed mids and good tonal separation. I also generally prefer instrumental music over vocals, with favored genres including jazz and classical music.


Our current headphones test setup uses a set of two custom in-ear microphones for the two channels. These microphones closely adhere to the IEC711 class, but have been tweaked to be more reliable in the >10 kHz frequency range, the precise issue with my previous setup, that is otherwise still very good and will continue to be used for IEMs and earphones. Two soft silicone pinnae are installed on the sides, separated by a distance matching my head, and multiple "height" adapters have been 3D-printed for further customization, based on fit, head size and shape. Each set of microphones has an XLR output I separately adapted to 3.5 mm. I used a transparent source—the FiiO K9 Pro—for measurements after confirming it was not a bottleneck in any way. This artificial head simulator feeds the microphone lines into a reference USB sound card, which in turn goes to a laptop that has ARTA and REW running. I begin with an impulse measurement to test for signal fidelity, calibrate the sound card and channel output, account for floor noise, and finally test the frequency response of each channel separately. Octave smoothing is at the 1/12th setting, netting a good balance of detail and signal to noise ratio. The default tuning was used for testing, and no app or program-based EQ settings were chosen, unless specifically mentioned. Each sample of interest is measured at least thrice with separate mounts to account for any fit issues, and an average is taken of the individual measurements for statistical accuracy.


As per usual, you can find my headphone frequency response measurements on VSG.squig.link, along with all the earphone measurements. Scroll to the bottom and choose different targets there, including two from Harman Kardon, developed after years of R&D. The Harman 2018 over-ear target in particular is a reference curve many headphone makers aim for now, but I find it too bass-boosted. As such, I am opting for the Harman 2018 curve with the bass target from the Harman 2013 curve, which is what is being referred to as the "Harman Combined" target there. Before we get talking about the sound signature of the HIFIMAN HE1000 Stealth, I want to first talk about the channel balance achieved here. You will notice how the left and right channels are quite close to each other all the way from 20 Hz to 20 kHz, which is the region of interest for human hearing. I did pick up the upper mids discrepancy when I was listening for it specifically, which I was only doing after noticing it in the measurements and not before. The higher frequency imbalances seen here are best taken with a grain of salt since this is well past the coupler resonance point. Needless to say then that there was no channel imbalance perceived here when I was originally testing the set. I will also mention that using the headphones for ~50 hours didn't change anything either for those who would undoubtedly be curious about burn-in.

HIFIMAN's house sound for open-back headphones tends to follow a neutral-bright sound signature. In fact, if you look at all the measurements I have taken then you will notice they are very, very similar to each other. But there's still a discernible difference between them when it comes to the technical performance of the drivers and the rest of the headphone design around them. With the HE1000 Stealth, I will say that it goes beyond just this and into a somewhat warm tuning too. In fact, I first listened to the set and immediately had to check with others who had it to confirm this was indeed a bassy set too. Purely by that metric, the HE1000 Stealth and likely also the HE1000 V2, carve out a niche for themselves in the expansive HIFIMAN lineup. Notice how the mid-bass rises slightly compared to the mids and this continues into the sub-bass too. It may not seem like much—especially compared to closed-back headphones—but this was enough to meet my desires for a decently punchy and detailed representation of bass guitars and drums alike. It's not going to have the slam and punch of premium dynamic driver headphones, including some that cost less, or even some planar sets from the likes of Audeze, and yet this made me smile and enjoy rock and metal music. Don't expect trailing ends of tones to stand out well given the typical planar decay, or lack thereof, but I suspect many will end up satisfied either way.

The mids end up coming slightly recessed by comparison, almost the point of making the HE1000 Stealth's tonality feel U-shaped. This can hurt vocals more than instruments that don't feel as forward-facing as I'd like, especially for non-baritone sounds and affecting higher frequency vocals further. The now-traditional HIFIMAN dip at 1 kHz contributes to this too by taking away from body and weight from vocals on top of what the HE1000 Stealth already has. In return, you do maintain excellent instrument separation and imaging throughout. Leading ends of tones for piano keys and brass instruments come off great here. I'd go as far as to say this might have the best timbre of any HIFIMAN headphones I've reviewed to date. What does keep this from being a top contender for instrumental music is a relatively narrow soundstage, which surprised me given my experiences with the other teardrop-shaped headphones from the brand as well as with that dip in the upper mids which tends to create a larger sense of space in my head. As I understand, the HE1000 V2 wasn't known for its wide soundstage to begin with and the stealth magnets have toned it down slightly further as they did with the Ananda and Arya before.

Going to the higher frequencies, things get less conducive for the masses. There's a trend of all the teardrop-shaped HIFIMAN headphones going on the brighter side with the exception of possibly the Edition XS, and the HE1000 Stealth is unfortunately leaning overly bright to the point of being fatiguing. The added warmth in the lower frequencies can help balance things out to an extent depending on the music being played but those leaning towards acoustic jazz and classical music may want to apply a broad EQ shelf of around -3 dB from 6 kHz onward to see if it helps. This improved things without taking away too much from the details, which is more than I could say about the HE1000se that goes overboard on detail and brightness to where EQ is much harder to do. As such, and also based on the better timbre and bass reproduction, I'd say the HE1000 Stealth is the best HIFIMAN HEK-series product I've ever tested! If you are particular sensitive to upper treble though then I would urge listening to this set before buying as it can be a potential dealbreaker.


I know some of you are already looking at this graph and thinking there's a serious lack of dynamic driver headphones here. I agree, but I can't do much about it in the absence of direct competitors from the likes of Sennheiser, Audio-Technica, Focal, ZMF etc. In the meantime, you'll have to make do with an all-planar round here that itself ends up going with just HIFIMAN and Audeze headphones at this point. The obvious comparison to the HE1000 Stealth would have been the HE1000 V2, but it was reviewed by Frederik way back in 2016 and I don't have one here. There's also the HE1000se which was the main source of confusion for me and others as to how the HE1000 Stealth differs from it, despite seemingly using the same diaphragm and other driver technologies including stealth magnets. The HE1000se is easier to drive, arguably looks better, is certainly more detailed and has a wider soundstage, but then ends up being overly bright and somewhat sibilant to where I can't listen to it for longer than 30 min without taking a break. The HE1000 Stealth has more bass, and better bass at that, while also being a better all-rounder set to where I would personally take this over the HE1000se and save the money.

While the newer Arya Organic might be a better comparison both price-wise and also from a seemingly similar sound signature based on impressions from those who have heard it, I have only the older Arya Stealth on hand which also apparently has the same driver technologies, down to the use of the HIFIMAN nanometer diaphragm—do you see how this can all be confusing, HIFIMAN? I would say the Arya Stealth comes off as a nerfed HE1000se in doing most of the same things, except it's less detailed and is easier on the ears when it comes to the higher frequencies. Right now the HE1000 Stealth is $400 more than the Arya Stealth and $100 more than the Arya Organic, but once again I'd say the HE1000 Stealth is the better set and worth saving the extra for unless you like the cleaner looks of the Arya Stealth more. If I get the Arya Organic in for review, I'll make sure to compare it to the HE1000 Stealth then. Last, and certainly not the least, is the Audeze LCD-X in its 2021 iteration that comes with updated drivers and ear pads. This is the best version of the LCD-X in my opinion and presents a nice balance of warmth and accuracy to where it's become extremely popular for music mixing and mastering alike. The newer Audeze MM-500 is a more neutral set whereas the LCD-X goes for forward mids and a darker signature thereafter. It makes for a completely different set to the HE1000 Stealth rather than direct competition, although it is much heavier while being built better too. I'd give the HE1000 Stealth the win for detail retrieval and instrument playback whereas the LCD-X handles vocals better; both are mediocre on the soundstage front anyway.