Reviews by jbfps116

My history with QKZ products has been… troubled. After somewhat liking their AK6 Titan, and then selling it due to the muddy mids, I purchased a string of other budget offerings from the company, trying to find something better.

THAT…didn’t go so well. Much to the amusement of the good people on Head-fi, they watched me lament about my foolish choices. I tried the SK5, an unnamed “9D super bass” set, the AK6 MAX, and the AK6 Ares. These sets were atrocious and had no redeeming qualities. Their bass was wildly bloated and their mids sounded like a boar thrashing in a muddy wallow. Even the AK6 Titan was several magnitudes better than those sets. I learned my lesson, and ignored the company.

Until I saw the ZXN pop up… I liked the look, and after months in my wishlist, in a moment of insta-regret purchasing, I pulled the trigger on a yellow ZXN.

When I finally put the ZXN in my ears, my jaw was on the floor…


Packaging and accessories: abysmal. The box itself has multiple huge spelling errors, and does not inspire confidence that the item is even a genuine product.

The cable is insta-toss quality. KZ-generic cable quality or worse. The IEM is advertised as having two different bore silicone tips, but they’re all of cheapest quality, and did not work for me. Luckily, the cable is replaceable [which is NOT the case for many QKZ IEMs. Read their descriptions carefully!] I first put a nicer upgrade 3.5mm cable on them for my initial impressions, and used Spinfit W1 tips.

I later upgraded to the Penon Vocal cable and Azla EarFit Max tips.

Sound impressions:
As I raved in an initial impressions post, the ZXN sounds so good, it’s as if a master IEM maker took over the QKZ factory and held them hostage until they learned a thing or three about making IEMs that ACTUALLY sound good, and they learned their lesson. It’s miles better than any other QKZ product, and shocks me with its capabilities every time I listen to it.

BASS: Unlike other sets from this company, the ZXN bass is definitely punchy, but NOT muddy, bloated, or intrusive. It has a perfect combo of sub-bass rumble that hits your gut, and mid-bass punch that can get you dancing without sounding overbearing that sets like the KZ Castor Pro Bass can get. The ZXN’s bass is surprisingly detailed capable, and I can see literally no downsides to it. It’s bass just as I love it: deep and punchy, never sounding weak or rolled-off, but done so at a perfectly balanced level to not drown out the mids.

MIDS/Vocals. This is the aspect that shocked me the most. All other QKZ sets I tried had deplorable mids [the AK6 Titan’s had barely passable mids, similar to the ND Venus, but both those sets I culled.] Mids are not recessed, to my ears, and are so clear yet not too clinical and dry. There’s a light dusting of musicality and warmth that polishes the diamond-clear vocals. It might not be the MOST detailed vocal presentation, but they are still very precise, forward and easily heard above even the most intense instrumentals. The vocals also minimally sibilant, even on the most challengingly sibilant tracks. That’s something other budget companies [KZ, I’m talking about you!] haven’t even ironed out yet.

Treble: The ZXN sounds airy and extended in the treble, and very detailed and HiFi. This is easily the second-most shocking aspect of the set. The treble is not piercing or sharp, but still clear and detailed.
This is treble that flies high above the V8 bass and clean vocals to provide the perfect crystalline sound and air to the soundstage.
It’s perfect treble for me!

Soundstage: It’s amazingly spacious. Rarely have I heard such great soundstage on budget single DD sets. It’s not ultra-wide or deep like better sets, but it’s good enough that I can get lost in the music for sure. I’m not an expert here, but I’ve definitely heard very well-tuned budget sets that have a smaller soundstage.

Details and separation: This is really an extension of me raving about the mids and treble. The driver NEVER sounds like it’s struggling. Hard rock/metal music? The ZXN handles it like a CHAMP! It’s easily on the level of the KZ ZVX Pro in this regard. Music remains detailed and clear even when tracks get challengingly intense, and this factor alone made my jaw drop many times.

Timbre: The musical tone of the ZXN seems fairly spot-on to me. I have sets that cost way more that cause me to cock my head at their weird tonality they give to some songs/instruments. This has never happened with the ZXN, at least for my unprofessional listening experience.

COMPARISON to KZ Zenith:
I think the ZXN can compete directly with the KZ Zenith [the most expensive single DD I’ve tried apart from the AirPods Pro 2] since it’s far cheaper, and lighter, so it’s more comfortable for longer listening sessions. Zenith is more of a neutral tuning and is also very, very clean and detailed. The ZXN, however, sounds more FUN while not losing HiFi integrity. The Zenith might be better for classical music due to its comparatively lesser bass quantity, and probably better driver which makes replicating various instruments more accurate, but the ZXN will still give a pleasingly clear playback of classical music, at about a third the price of the Zenith.

Comparison to the KZ ZVX PRO:
I have not extensively compared the ZXN to the KZ ZVX Pro, but off the top of my head, [and with a hasty A-B session,] the ZVX Pro is equally capable, if not better when it comes to separation and detail, [especially in the bass,] but it can come across as dry at times. The ZXN always sounds JUST musical enough to sound smooth while being very detailed. They are about equal in jaws-dropping, spine-shiver-inducing awesomeness, with the ZVX Pro I think edging out the ZXN on dynamic bliss, at least when that hidden gem of a KZ set isn’t sounding too clinical, especially apparent in vocals. ZXN just does vocals more smoothly, and is more fluidly lyrical. Also, my ZVX Pro set has minor driver flex. The ZXN has none, unlike nearly all the other cheap QKZ sets I tried.

Cons and Conclusion:
What would you be missing with the ZXN that you WOULD get with better sets? For the price, nothing, but better sets are better at detail and separation and soundstage, and even more technical bass, but for single DD sets, I’m not sure I’ve heard any that are remarkably better than the ZXN. [Granted, all my more expensive sets are multi-driver, besides the AirPods Pro 2.]

To end this wall of text, I’m trying to think of a reason for someone to NOT buy the ZXN. If you rely on stock accessories, you might still consider it because they did sound good even on the 3.5 cable. If you like IEMs that seal well, you’d have to change up eartips. They are comfortable, but lightly-built, and the shells provide little isolation [although they aren’t as bad at this as the TFZ T2 Pro.] If you’re frightened about the possibility of a budget IEM entrancing you so much that you become less enamored with your more expensive sets, then definitely AVOID the ZXN, because it will blow your socks off, and at that point, it’s just getting started!

Why am I writing a review for a pair of laughably cheap IEMs? Would anyone even look up a review for these? No. But I'm doing it anyway, mostly to vent.

The hallmark trait of these IEMs [it feels offensive to call these by that acronym because "monitors" does NOT apply to these whatsoever] is that nothing they claim about the SK5 is true. Let's go through that, in the order pictured in the item description above:

Looks: "Real product is more amazing than in pictures."
FALSE. They look super cheap, although the color I got, lemon yellow, does match the pictures. But they don't look very good in person.

Frequency Response claim: 20-20k.
BARELY. The highest tone I could hear was around 17kHz, and I know I have good hearing. Reasonably though, you probably won't hear much high treble here. They could reproduce a tone almost down to 20hz... actually I was impressed it could do that.

Great sound: They claim it took them 5 months to tune these to take into account "surging bass and warm, sweet vocals."
FALSE. I admit sound is subjective, and while these have a reasonable bass response for the price, vocals, male and female, sound muffled and unclear.

Driver: In some product pictures, it says it's a 10mm driver, in others, a 11.6mm driver. Maybe I should crack these open to check! As far as it being composite graphene, I doubt it!

Fit: "Comfortable to wear, not easy to fall [out.]
FALSE. Again, a subjective thing. These have a VERY odd shape and fit, and first of all, isn't very comfortable unless you find the right tips [almost impossible] and they never feel secure. Not having molded ear hooks doesn't help!

In-line mic, play/pause button, and volume slider:
Works. [Did not test the mic] The button and slider work ok.

"Amazing details [assuming this means accessories?] including 2 sets of functional earplugs."
FALSE. Again, subjective, but I found almost no ear tips gave a proper seal and fit. JVC spiral dots work the best. Included tips are junk.

Sound impressions and comparison to another cheap single DD, the KZ ZVX:
[I'm not super good at describing sound, so apologies for this non-professional review section:]

Bass: This is the best part of the sound spectrum on the SK5. It's your typical fun sound, but feels like somehow the driver is underpowered and it can't thump like it should be able to. Maybe not being able to upgrade the cable is problematic here. ZVX bass is far more clear and even more punchy.

Mids/vocals: Mids feel recessed, muffled, and low-fi. Like so much so that I don't even want to give this set away. Guess the tuning team wasted 5 months of their lives, although admittedly, I bet QKZ gave this set the cheapest possible materials, which would be hard to work with. The vocals also sound distant, in an unpleasant way. In comparison, the ZVX sound like a TOTL set. I'm not kidding! I wonder if the driver is not as bad as I make it sound, but the cheap plastic housing badly affects the sound. On busy tracks, the mids, and really, the entire sound spectrum falls apart into a jumbled, incoherent mess.

Highs... Some sibilance detected. The highs aren't terrible, but again, there's not enough clarity for the treble to really shine like it does on the ZVX.

In short, the entire sound is so bad, it feels like a throwaway product. 1.5/5 because they ARE better than airline earbuds, actually significantly more so, but for them to be flashing the Hires Audio sticker on their advertising is simply misleading.

Who are these for? Sound is about at the quality a child would appreciate, but the fit is so awkward that they might have trouble even wearing them. So I think the SK5 should have been never produced. Even the marginally more expensive QKZ AK6 Titan sounds leaps and bounds better than the SK5. Buy that instead if you're this money-conscious.

I got the non-tunable version for very cheap on Aliexpress, and it did NOT come with the extra fancy tips that some of the other reviews showed. I felt the generic KZ silicone tips did not get a very tight seal, so I put some Spinfit W1s on these, and they are perfect for the D-fi!

I ran them through my music test and they performed VERY well... not because they are BETTER than the other more expensive IEMs in their score bracket, but simply because these single DD wonders just sound GOOD no matter what genre they play. I liken them to a very decent Bluetooth speaker that has a signature sound you love, or maybe a decent factory car stereo. Definitely a crowd-pleasing sound!

Even though I did not get the switch edition, I feel the factory tuning is amazing, and is bassy enough for even hard rock, pop, and EDM music, something that other, more expensive sets I've tested cannot claim.

The vocals are not recessed, and have a reference, yet friendly quality to them that makes them addictive to listen to. Compared to my previous favorite single DD from KZ, the EDX, these are in a whole other ballpark.

The highs are definitely present, but compared to the ethereal highs of the ZS6 or ZS10 PRO 2, these are merely adequate. But because of that, they have no sibilance, even on tracks that can be prone to it. The highs are smooth, but crisp when required. I would simply like a bit more treble boost.

Are they worth the MSRP of around 30$? yes, but if you can find them cheaper, the better. There's so many sets around 25-35$ that are nice, and I'm sure this one is better than many. It's definitely better than the Tangzu Wan'er that everyone raves about, in general tone and bass response, although the Tangzu comes with way better accessories.

I'm getting in some more highly-praised cheap single DD IEMs in soon, so I will update this review once I can do some comparisons!

Mar 10, 2024
The following review is an expanded version of the review I posted on the kztws website. I could only use 2000 characters there so I'm expanding my thoughts here.

MY RATING: 9/10 STARS. So I've heard a LOT of criticism about the Symphony... As a casual music listener I hope to dispel some of the concerns with my honest review. I bought these with my own money.

BUILD: 10/10. These look stunningly handsome and professional. I love the metal grille and underlying mesh. The build quality is very good like all KZ products I've tried.
FIT: 8/10. Yes these are large buds, but they fit my ear well and the medium silicone tips create a perfect seal. I've never liked memory foam tips, and the ones included with these don't work for me either. I've noticed only slight fatigue in my ear canals during long listening sessions. Paired with the KZ AZ20 Bluetooth adaptor, they are overall a quite comfortable earbud and has no risk of falling out.

OVERALL SOUND: 9/10. I am not an audiophile but I like good sound quality. I do NOT use a DAC or other amp, and use Amazon Music for much of my music. I do use an EQ on my other music apps, and these IEMs are very responsive to EQ changes. These benefit from a "vocal booster" EQ but on Amazon Music with no EQ, they still sound great. On the AZ20, I always use the "full power mode" which enhances the sound quality. I don't feel like they are too "hard to drive," and they sound good both on the Bluetooth adaptor and wired with an Apple 3.5mm dongle. You simply have to have the volume set a little higher than with other earbuds. The overall sound is pristinely clean and clear, and rival multi-armature driver sets in detail. This my first time owning a planar driver IEM and I can say I love the sound they produce, and look forward to trying some other planar driver sets in the future.

BASS: 9/10 These have more bass than the EDX. I'm talking SUBWOOFER-level bass. That 6mm DD that YouTubers derisively call a "pencil eraser driver" really can pump out quality bass. At times though, the bass can be almost too much for even me! These are what I would consider "bass-head" earbuds, but sometimes I want to turn the volume up but can't because the bass is at my max comfort level. Sometimes I enjoy heavy bass, and while the bass response here is amazing, I'm docking one star from an otherwise perfect score because it can be just a bit too much on some songs.

MIDS: 7/10. Yes, the mids are a bit quieter than the bass and treble, but they are accurate and pleasantly warm. Like I said earlier, they do sound better with a slight boost in the mids with EQ, but the mids certainly aren't overly recessed, muddy, or vague like some cheaper sets I've heard.

HIGHS: 9.5/10. I hesitate to give a perfect score here, but the high end is really perfect: not too harsh or shrill, but elevated enough to give sparkle and shine to the music. They don't have the celestial highs of the ZS6, (which many have rightly criticized as being overly extended) but are still very pristine and a delight to the ears. The planar driver can compete quite well with armature drivers in this regard.

CONCLUSION: These aren't a "monitor" set. They are excitingly dynamic and outshine all of KZ's older sets I own. (EDX, ZS6, ZS10, SKS, ES4, EDX PRO X) They really sold the planar driver for me, and now I want to hear one of the PR sets to see how the bass response sounds without the in-ear 6mm subwoofer!