Superlux - HD681F

TL;DR for those short on time or not inclined to read the entire review: # Pros * Pleasantly warm and colored mild V-shaped signature with pretty good technicalities and responsiveness to EQ * Very wide soundstage and punchy bass * Well built and very comfortable to wear, also thank to the thick pads and the self-adjusting headband * The earcups twisting mechanism is a game changer * A pair of velour pads is included in addition to the pleather pads * Very long and durable cable # Cons * Not really “studio-accurate” since the bass can become very prominent in genres like Hip-Hop, EDM and similar stuff * Improvable imaging precision and treble extension up top * The colored timbre could be pleasant for some but might put off those listeners who prefer a more natural reproduction \------------------------------------------------------------------------------------------------------------------- # Introduction Kiwi Ears is very popular in the Chi-Fi community, especially thanks to some of their models such as the Cadenza, which have been a default recommendation in the budget segment. A lot of time has passed since the release of the Cadenza and in the meantime Kiwi Ears has released many other interesting IEMs and full-size cans.  Speaking about full-size cans, Kiwi Ears has recently released a pair of open-back cans that sit in the sub 100$ bracket named Altruva, which will be the star of this review. >*Disclaimer: the Kiwi Ears Altruva were sent to me by Kiwi Ears free of charge so that I could write an honest review. This review represents my personal opinion on the set, it isn't promotional or paid content and I don’t get any revenue from the sales of this product.* *At the time of the review, the Kiwi Ears Altruva were on sale for about $69 at Kiwi Ears*. https://preview.redd.it/vhxwgkk0ajof1.jpg?width=1500&format=pjpg&auto=webp&s=0d985f175c59275beef008da693a602d21959dcd # Technical Specifications * Driver Configuration → 2 x DD * Impedance → 17 Ω±10% @ 1 KHz * Spec-sheet Frequency Response → 8-45 kHz * Effective Frequency Response → 20-20 kHz * Sensitivity → 120dB @ 1Vrms * THD → <0.05% @ 1 KHz 94dB * Cable → 1,2m cable with 0.78mm PINs * Plug type → 3.5mm, 4.4mm, Type-C DSP-FORCE plug (with compatible companion app) # Packaging # The Kiwi Ears Altruva come in a simple package that contains:  * The Kiwi Ears Altruva * A detachable cable with 3.5mm plugs * A pair of spare velour earpads The fact that a pair of spare velour pads. in addition to the already mounted pleather pads, is included is already a plus. # Design, Build Quality, Comfort and Isolation The Kiwi Ears Altruva are well built, they look and feel pretty solid, there’s a pleather self-regulating strap secured to the headband by metal screws and everything feels pretty solid despite the low overall weight of the headphones themselves. There's also a wooden version of these, which looks better than the unit you see in the pics below here in my opinion. https://preview.redd.it/tbno2uop9jof1.jpg?width=1500&format=pjpg&auto=webp&s=f7fe422dd7bdd80c455c7cc2bafec118a5a7e5d1 https://preview.redd.it/iqipqtop9jof1.jpg?width=1500&format=pjpg&auto=webp&s=e13f01d69bc1ec8da1116a9d9bfcd45d5d375428 https://preview.redd.it/g5sn0vop9jof1.jpg?width=1500&format=pjpg&auto=webp&s=88835a7e01602595ec5fc2605d9a7ecce0f3767d https://preview.redd.it/rd5p8uop9jof1.jpg?width=1500&format=pjpg&auto=webp&s=b76728c3520731ed2260b37d3ce8d1617ee954e1 The earcups don’t have horizontal swivel but there’s some vertical swivel so there’s actually some headroom for adjustment. They can also be detached by simply twisting them, and this makes earpads swapping very easy to do (there’s a pair of spare earpads made of different material in the box so all of this is very appreciated). https://preview.redd.it/1i9nmxvn9jof1.jpg?width=1500&format=pjpg&auto=webp&s=b8dd213aebdead568f01acaddf0d3609a5abc5da https://preview.redd.it/dmn5exvn9jof1.jpg?width=1500&format=pjpg&auto=webp&s=0eb930d0a31c0f32bbf010b17214b79bd8ca8920 The comfort is excellent, mostly because of the self-adjusting headband (which evenly distributes the weight on the head) and the thickness of the pads, whereas isolation doesn’t really play any role because we’re talking about a pair of open-back headphones. # Cable The cable is detachable, it’s very good and due to it being braided it also looks and feels durable. It’s probably one of the longest stock cables that I’ve seen in a while, and that’s meant to be a solid companion for those who use the headphones in a studio or that just want to move without the cable being an obstacle because of its shortness.  It’s not microphonics in general even though a couple microphonics episodes could happen in the last parts of the cable (after the V split, the two cables that go into the earcups are a touch more microphonic). https://preview.redd.it/95x9ulxx9jof1.jpg?width=1500&format=pjpg&auto=webp&s=661b3cfd98907ffdc66240d34977a3b081dc33b9 # Sound **GEAR USED FOR THE TEST** * DAC: Topping E30  * AMP: Topping L30 * Mobile phones: Samsung Galaxy S23 Ultra * Moondrop May’s DSP cable with PEQ=0 * Dongles: Apple Type-C dongle, Fosi DS2, DUNU DTC800, Truthear SHIO, Tanchjim Luna AT * Portable DAPs: Snowsky Echo Mini * Bluetooth DACs: Snowsky Retro Nano, FiiO BTR11 **Amplifier needed?** The Kiwi Ears Altruva don’t strictly need a desktop amplifier but a decent dongle is definitely a must. **Let’s speak about the sound.** Kiwi Ears says “the Kiwi Ears Altruva delivers a studio-accurate sound with rich detail, balanced tonality, and breathtaking soundstage”, and even though not everything of statement is completely true, I gotta say that most of the things actually represent what the Altruva are. It’s a set that sounds colored for sure, and there’s some added bass and treble that brings some warmth to the sound, making it more appealing and richer than your average neutral headphones, moving towards a mild V-shaped signature rather than being a truly “neutral” set. This means that calling them “studio-accurate” headphones isn’t really something I would do, especially if you listen to music that involve lots of basslines such as EDM, Pop and electronic music in general, since the bass boost actually makes them way warmer than a studio-accurate set should sound like. When listening to tracks that don’t really feature a lot of sounds that belong to the lower frequencies, instead, the Altruva sound more balanced overall and show more versatility, being able to portray vocals and instruments as expected from a “studio-accurate” headphone. The bass itself also has decent texturing which is not common for this price range. The midrange has a touch of warmth in general but the instruments are correctly presented and separated overall, although the timbre, as said, can be slightly colored if there are some basslines going on. Same applies to vocals even though the warmth kinda helps giving them some added body so it can also be a strength in some cases. The treble has nice extension and there’s a good amount of information up top, but if you’re searching for a super analytical and airy set I guess this is not the most resolving headphone you can get: the treble, in fact, is detailed, but things are kept sustainable for long listening sessions by avoiding annoying peaks or too much brightness, and although this guarantees fatigue-free listening sessions, this has some trade-offs in the perceived resolution and in terms of that last bit of extension and air. The **soundstage** is spacious as expected from an open-back set (especially in terms of width, which is crazy good for the price), and the **imaging** is more than satisfying considering the price range. Due to the very wide stage, sometimes imaging is not as sharp as on some other open-back sets (i.e. DT990 Pro) since sounds play in a wider soundstage and they’re more “diffused” in a bigger space, rather than nearer and easier to pinpoint. When listening to tracks that don’t involve a high quantity of basslines and kickdrums, it feels like the imaging is even a touch better so I guess that the sharpness of the pinpointing also depends on what you listen to, and this is mainly related to the midbass emphasis. **Gaming?** Thumbs up, if you just game casually on FPS or if you want the best immersion for open-world games: the Altruva do a very good job during these types of gaming sessions and could be great gaming companions if you pair them with a simple clip-on mic or Modmic. If you instead want a set for competitive gaming, a heavy EQ would become mandatory since you have to clean up the boosted low-end and revive the 1.5kHz and 4kHz region. I would still prefer a pair of good in-ear monitors for competitive close-quarter FPS games such as Rainbow Six Siege, Counter Strike and similar titles (i.e. Simgot EM6L, Moondrop SSR, Simgot Supermix 4, Simgot EA1000 and so on) since the imaging would be cleaner and pinpointing would be easier. **Is EQ a thing?** Since sometimes people ask me about the EQ, the Altruva can take EQ like a charm so if you’re willing to tone down the bass a little bit, they will definitely respond very well to EQ. I have tried to make them a bit less forward in the midbass region and obtained a less colored response and more transparent midrange (if that’s what you want).The fabric earpads also prove to be a small fine-tuning tool since they make the sound even warmer and add a small touch of midbass: this could mean too much midbass for some even though fabric is much more tolerable during summer periods so that’s a trade-off you may want to consider. **Are they something I would use considering my taste and preferences?** Yes, the sound coming from the Altruva is good, they take EQ in a very responsive way and they are also super comfortable, so it’s a set that I will definitely keep using when at home. # Some comparisons: **Kiwi Ears Altruva vs Sennheiser HD560S (1st version)** >I do not own a pair of HD560S, but I have been able to put my hands on a pair for this review since I had tried them a couple years ago and didn’t remember how they sound like. Being very brief, the 560S are more neutral, they sound more accurate and natural in terms of timbre and they have less low-end emphasis and a touch less treble compared to the Altruva. This translate a in a more coherent and uncolored sound, at the expense of some low-end punch and body that instead can be found on the Altruva. Both take EQ very easily, both perform well considering their price, but the HD560S is a superior pair of cans that sounds more proficient and more correct in terms of tonal balance most of the times. Weaknesses? Well, the HD560S don’t have a very exciting and full-bodied low-end and they have a small peak in the lower treble area that might bother some folks; the Altruva, instead, sound less energetic in the treble area due to the bass emphasis that counterbalances the treble energy, but the bass itself is sometimes too prominent and might bug some types of listeners. The soundstage is pretty wide on both sets but while the Altruva have a sort of caverniculous soundstage (due to the enhanced low-end presence), the HD560S play in a similarly wide open-space (for the sake of simplicity, it’s like comparing a big closed hall to and open air stage). The HD560s do a slightly better job with height, if I have nitpick. The imaging is okay yet not excellent on both sets since the very wide stage representation makes pinpointing more “diffused” around the field, especially when It comes to vocals that usually sound more centered even when they should be placed a bit more towards one side of the stage.  Build quality is good on both sets but I’m impressed by the fact that the Altruva are being sold for a much lower price yet their touch and feel is sometimes even better than with the HD560S. Another plus is the twist mechanism to remove the earcups on the Altruva, which makes pads swapping basically hassle-free. You also get a pair of added velour pads in the box with the Altruva, so you have both pleather pads and velour pads (i.e. it’s a great addition for summer since you can use velour pads if you think pleather pads are annoying when the temperatures are higher). The comfort is great on both sets so I have no complaints about this in both cases. Isolation? They’re both open back, so not something to consider. The stock cable of the Altruva is super long and braided and it also feels a bit sturdier but overall the HD560S come with a decent cable as well. **Kiwi Ears Altruva vs Hifiman HE400SE** >Some could point out that it’s not fair to compare a pair of headphones using a dynamic driver and a pair of headphones using a planar driver, and that’s a fair point, but it’s also true that some could stumble both of these sold at a very similar price and struggle to make a decision. Well, the differences are quite remarkable since the timbre is very different: the Altruva sound warm and have some bass emphasis, whereas the HE400SE are brighter, with a more forward midrange and less low-end quantity. Something that immediately pops up is the difference in terms of low-end: while the Altruva go for more body and thickness, the HE400SE have less bass quantity, less punch, but better speed and less bass bleed into the mids (this difference is very common when comparing DD headphones with planar headphones, on average). This makes the lower midrange warmer on the Altruva, leaner on the HE400SE, making Kiwi Ears’ headphones more appealing for those who mainly listen to male vocals. The HE400SE, on the other hand, have less upper midrange boost compared to the Altruva, but some now the much more controlled low-end makes female vocals pop-out a bit more with more energy and extension and with a more accurate timbre, especially in terms of vocal harmonics (female vocals fundamentals, instead, could sound a bit richer on the Altruva). The treble is brighter and more energetic on the HE400SE, and this both because of their mid-treble emphasis and the lower quantity of low-end that doesn’t act as a counterbalance as much as it does on the Altruva. The treble on the HE400SE is more detailed and open-sounding, but it comes with a couple timbrical quirks when some cymbals are being reproduced; it’s not a dealbreaker, but if you’re treble sensitive, the Altruva might be a more tolerable set when it comes to the upper-frequencies.  The soundstage is pretty good on both sets but the Altruva are a notch above since they play in a wider and deeper soundstage. The imaging and separation, however, are a touch better on the HE400SE, I guess also thanks to the brighter and less bassy response. Both take EQ very well so you might be able to fine tune both of them, but the planar driver of the HE400SE have a slight advantage in terms of speed, even though you'll need a much more powerful source to drive them (this is the caveat). The overall build quality is good on both sets considering the price, maybe the Altruva look a bit less “professional” but both are sturdy enough to guarantee prolonged usage (lemons, unluck and driver issues apart, which can happen with any headphones). The twisting mechanism of the Altruva, as said in the previous comparison, is another plus if you decide to get them: replacing pads is super easy. Comfort goes to the Altruva: they are a lot more comfortable for me, especially because the self-adjusting headband evenly distributes the weight of the headphones on the head, a thing that doesn’t happen on the HE400SE that can be adjusted through lateral sliders but that lack proper weight distribution on the head (fixed and centered headband, which doesn’t even have super soft cushioning). Plus, the Altruva has thicker pads and this adds more space between the ears and the internal plastics covering the transducers, somehow altering the perception of the soundstage (that May seem wider) and by making the headphones more comfortable as well since the ears never touch the earcups directly. And yeah, the Altruva also come with and added pair of velour pads, which are more than welcomed. No isolation comparison again, both are open-back. The Altruva also win when it comes to the stock cable: it’s longer, it’s braided, it’s softer and more comfortable, and it’s not as microphonic and stiff as the cable provided with theHE400SE.  **Kiwi Ears Altruva vs Superlux HD681-F** >This comparison Is basically a bonus, but I wanted to write this because I know some folks who have some old Superlux models like the HD681-F that I won and would like to know if something like the Altruva could be worth the upgrade. To be fair, the Altruva and the HD681-F sound VERY different, and it’s very evident that the HD681-F are older and cheaper: a much less refined sound, worse build quality, worse and non-detachable cable, stiff and thin stock pleather pads (and pleather is actually low quality too) and so on.  The Altruva are priced way above the price tag at which you can still buy a pair of Superlux HD681-F nowadays, but the differences in terms of quality is huge. The sound of the Altruva is a lot warmer, you get a thicker and more textured bass, you get a more controlled treble and also more natural vocals (not neutral, since they’re a bit colored on the Altruva, but they’re more natural for sure), less sibilance, better technical performance, a much better build quality, better quality and thicker pleather stock pads (and you also get a pair of velours pads in addition), and a longer and sturdier detachable cable. I mean, you could swap the pads on the HD681-F in order to have thicker and more comfortable pads on them, and you could also EQ them, but this won’t push them enough to reach the level of the Altruva, despite them being an affordable set of cans and not something very expensive. The market has evolved and we have many different models to choose from and even though Superlux was a sort of “light in the dark” back then, there are some products that are worth buying if you want to make the jump from a pair of Superlux cans like the ones I’ve used for this comparison, and the Altruva are definitely among the sets you should keep an eye on (and you can also EQ them since they are very responsive with EQ). # Final Thoughts Kiwi Ears is on a roll, and I’m quite impressed with the overall value of the Altruva. You get a warm-sounding set with proper bass body and a big soundstage, and the good quality of the driver makes EQ very easy to do (if you’re someone who likes to play with EQ or if you find the bass too prominent at times). In addition, the build quality is good, the comfort is great and the headphones also come with a pair of spare pads and a very long braided cable. The Altruva are not perfect, though, and despite being promoted as studio accurate, they don’t sound as neutral as expected (this can be a pro or a con depending on the user): the bass emphasis, in fact, is evident, and thickens the sound making everything warmer and slightly less transparent than expectations. However, the sound coloration is kinda pleasant, so if you’re searching for a balanced-sounding set that has some coloration to make things fun, this set is definitely a keeper. Good job Kiwi Ears, a big thumb up for you.

These will work out of your PC if you don't have a very old PC. My suggestion, however, is to get a cheap 5-10$ dongle like the JCally JM6 or an Apple dongle Type-C (with a Type-C to Type-A adapter) in order to have a slightly better sound out from it. If you can stretch to a JCally JM7 Max or JM6 Pro, then it's even better. They do good for gaming with stock settings, but games like Rainbow Six Siege/X, Warzone, Escape from Tarkov and so on will be a bit better with a pair of neutrally tuned or bright-sounding IEMs such as the Simgot EM6L, Moondrop SSR and similar stuff. If you wanna EQ these, however, you can overall improve them with a couple filters that you can find a couple comments below in this comment section.

Have my superlux hd 681 for like 4 or 5 years, and they are awesome, using them for music and with the threaded extension I can use them for my guitar amp too, top tier and dirt cheap.

Superlux HD681 and Samson SR850, but with velvet/suede earpads. Eh with stock shitty leather. 100-200$ sound with velvet pads. KSC75 if you don't mind the hooks. Moondrop Old Fashioned is really nice as well, sounds pretty similar to KSC75.

ath m40x are the worst headphones ever, I bought a superlux 681 and found out bass existed for the first time

I'm using the 681's right now with sonarworks ID it sounds pretty good better then the audio technica m40x

Out of these, I've tried the Sony and both superlux hd668(b) and 681. The superlux hd668b sound-wise is the clear winner for me. Good detail, excellent for the price, clear yet impactful bass and just a really pleasant sound signature overall. The are a little fragile though ime, with the cable failing twice on mine after ~1-2y. My third set has been holding on for longer, but that's probably because I have used them a lot less after upgrading

Superlux HD681s the GOAT (if you replace the pads). I think I prefer them over my SHP9600s.

I've only had two but here's my two cents: HD 681 is absolutely crazy for the price. HE400se is a really fun pair to own. Some people say it can trade blows with headphones above its price and I believe them.

I wanna throw Superlux headphones into the ring. I own a pair of HD681 since over 10 years, they are semi open and have astonishing sound for die 22$ they cost. (And don't need a driver) [https://www.rtings.com/headphones/reviews/superlux/hd-681](https://www.rtings.com/headphones/reviews/superlux/hd-681) I think they also have the same size ear cushions as Beyer and can thus be replaced with them.

I love my Superlux HD681, a little EQ and maybe different pads and they are lowkey amazing.

I always recommend Superlux HD681s for a solid budget option.