Hiby Zeta ($1,399)
Intro
This is my full written review of the Hiby Zeta, which happens to be Hiby Audio’s latest flagship iem. This is Hiby’s first try at what would be considered an “end game” iem (at least that I know about). I want to thank Hiby for including myself as well as mobileaudiophile.com in the review tour of both the Hiby Zeta and the Hiby R6 Pro 2 (gen. 2). I greatly appreciate the time I’ve been able to spend with these two audio devices and I do hope that this review will help in making a purchasing decision. Truly this has been an eye-opening experience in getting to spend time with the Zeta.
Hiby
The audio company Hiby has been around for quite some time, since around 2011 and have mostly specialized in their Digital Audio Players (DAP) as well as smaller dac/amp dongle for mobile uses. Hiby seems to specialize in R&D, and it is evident in their products. I haven’t been able to actually test out most of Hiby’s products besides the Hiby R3 Pro 2022 as well as the Hiby R6 Pro ii (also part of the tour). That said, they have a very extensive list of Daps from the budget sector all the way to the high-end arena. One of these days’ friends. Hiby also has a very nice list of Dongle Dacs and even a few True Wireless to round out their product list. Truly it’s quite impressive. I suppose that I had no idea how extensive it was until I really dug deep through Hiby’s history.
Along the way Hiby has also gravitated to the in-ear monitor side of the audio game and actually created some very well done iems for their time. Namely the Hiby Seeds, Hiby Seeds II, the Hiby Crystal 6 and its successor the HIBY crystal 6 II. Even their budget oriented Hiby Beans was a nicely tuned bullet style iem which didn’t get very much attention but certainly should have. I was able to check out the Hiby Seeds 2 and I’ll be perfectly honest, the Seeds 2 is a fantastic iem that fell almost entirely under the radar. It is a shame because it is truly a fantastic V-shaped set.
End Game
I haven’t reviewed any real TOTL sets past the $1,000 price point, I just want to be honest. However, I do think that I can give a good account of just how well, or not, the Zeta is tuned, and what kind of value it is. One thing is for sure, Hiby is trying to nip at the heels of the best iems in the business. The Zeta is truly a phenomenal example of artistry, coupled with knowledge, coupled with skill as well as the ability to put these all together to form a product they can be proud of. Certainly, they should be proud of this one, let’s just get that out of the way right now. Surely at least for some, the Hiby Zeta will be an end game iem. That said, I will do my humble best to present the Zeta in the truest light that I can. The Hiby Zeta everyone…
Purchase the Hiby Zeta:
ZETA Pros
-Gorgeous packaging
-Build Quality is phenomenal
-The design is very fresh and sleek
-That purple/blue cable is DOPE!
-Great coherency between nine drivers in a tribrid form
-Deep, controlled, & penetrating lows
-Very lush and resolving midrange
-EST treble is beautiful and non-offensive
-Treble extension is nice
-For the tuning I find detail retrieval to be well accomplished
-Holographic soundstage
ZETA Cons
-Price
-lower midrange is a little unrefined
-Some may want more treble vibrance
-The Zeta may have too much low-end emphasis for some
Gear used for testing
-Ifi Go Blu
-Hidizs S9 Pro
-Moondrop Dawn 4.4
-Hiby R6 Pro ii
-Shanling M6 Ultra
Packaging
The Hiby Zeta arrived at my front door in a slick looking rectangular box with a neat looking gold on black design. Upon removal of the box top you are instantly met with the bold and beautiful looking Zeta earphones sitting pretty in cut-out foam partitions. The earphones themselves sit on one side of the box and the storage case box is on the other side. Now I am only assuming “how” the Zeta was packaged, as I have a tour unit, and nothing arrived at my door where it was supposed to be inside the box. So, if the picture I attach is not correctly “put together” than please forgive me.
That being said, I think I have it figured out. Anyways, under the earphones you’ll see an accessory box which when opened has a tray full of eartips. Hiby also added two little drawstring bags to protect the earphones, a magnetic cable clasp and a cleaning tool. Lastly, as you look inside the beautiful case you will find the cable. I realize I wrote this very dry but in truth the unboxing experience is quite nice after you are done uncovering all of the goodies provided. Is this a $1, 400 unboxing, and is it $1,400 good? I suppose that’s debatable. For what it’s worth I think it’s more than fine and the quality of the the accessories speaks volumes. Not bad at all Hiby.
Carrying case
The case that Hiby chose to provide is a really premium looking leather case in a short cylinder style. The case has a fresh-looking color of blue and instead of using a zipper or a magnet to open and close, this case instead simply slides off and on. Really there is enough resistance and grip to hold and protect these very expensive earphones without worry of the case lid falling off. In the center of the carrying case is the brand name “Hiby” which is encircled by some nice-looking stitching. Inside is a soft material for keeping your gorgeous Zeta earphones protected and cushioned.
Ya know, I never use a case and if I do it’ll be something simpler and pocket friendly. Also, who is taking their $1,400 earphones out and about? That’s what sub $200 earphones are for. However, I digress, the case is more than adequate and truly suits the whole mystique and premium vibe of the Hiby Zeta. It’s a very nice addition.
Eartips
Hiby provided a slew of very nice eartips with the Hiby Zeta which I would easily utilize with some of my earphones. They give you three pairs (S, M, L) of wide bore tips that have a shallower fit and have a nicely firm flange. Hiby also provides three pairs (S, M, L) of some medium bore silicone tips which are a bit longer and fit deeper in the ear. The last set of three tips (S, M, L) are actually some hybrid silicone and foam set of tips which are also of very good quality. Nine pairs of tips in total and all are able to slightly skew the tuning of the Hiby Zeta. I actually ended up using the included straight silicone tips but did spend time with each set and even used some 3rd party tips. Other tips which I found nice with the Zeta are the KBear 07′s, the Tenmak Whirlwind tips, Dunu S&S Tips and the TRN Clarion tips.
Cable
The provided cable will either be adored for its crazy contrast to the colorway of the Hiby Zeta, or it will not be pleasing at all. This was an odd choice or a genius choice by Hiby. You have a strikingly beautiful iem of silver Titanium with textured matte silvers and a high mirror polished in artistic portions of the faceplate only to have a bright & vibrant blue/purple cable. It certainly wouldn’t have been my first choice. However, I like it, shows how much I know. I think it’s another nice addition and absolutely love the pairing. In the same breath I could easily see some of my fellow hobbyists looking at it with a puzzled glare. I think the cable is gorgeous and very well mannered and it isn’t microphonic at all. The cable is pliable, soft enough, it rolls up nicely, and is just beefy enough to look premium.
The included cable is a 22AWG, .078 2-pin, 8-core Litz fully balanced OCC Copper cable utilizing a 4.4 plug. Again, Hiby chose the Litz braiding, which is nice to see, not my favorite but nice. Hiby promotes the cable as having a low resistance and a low loss signal transmission. Due to the fact that this cable came with the tour unit I didn’t swap cables and simply went with the included wire that was given and so I couldn’t test out any other cable combos with the Hiby Zeta. In my opinion it isn’t bad. Of course, we’ve seen seemingly better cables in earphones for much less, but it’ll get the job done and looks flat-out DOPE paired with the Zeta. To be honest I think it complements the mirror finish of the Zeta nicely and really helps the silver POP somehow. Very nice but I’d understand anyone not enjoying it as much as I do.
Build / Design / Internals / Fit / Drivability
Build Quality & Construction
Titanium is the material of choice which was used in the construction of the Hiby Zeta and judging by the feel and weight I feel that Hiby made a nice choice. They could’ve used any material at the price the Zeta is being offered for, but they went with a very light and durable material in Titanium. Titanium is actually quite ductile and has a very high strength-to-weight ratio. Obviously, this is a bit overkill for a set of earphones, but the material certainly looks nice and feels great in hand and in the ears. The actual size of the Hiby Zeta is a pretty chunky so to fit all those drivers inside so do be aware. We already know that there is a 2-pin connection at the back as well as one small back vent under the female 2-pin connection. The nozzles maintain the titanium matte texture all the way to the nozzles and is capped off with a nice metal mesh grill.
Design & Aesthetic
This is another area where the Zeta will either blow you away… or not. For me, I think the design is absolutely gorgeous. The entire shell has this matte silver (titanium) surface that is textured to a degree. Also, the faceplates have these mirror polished squiggly lines (possibly lightning?) which only cover about half of the faceplate and look so appealing to me. I think it’s a fantastic design touch. Truly premium in every sense if the word. Possibly a little boujie but also pretty tough looking in the same sentence. The finish of the shells offers this soft glow in the right light and is very smooth to the touch. Hiby also etched their company name into the faceplates as well which doesn’t look bad but would probably look better somewhere else. The Hiby box actually states that this is an “artistic” iem. I’m not entirely sure what that means but based on the look of the Hiby Zeta, I think I have an idea.
Youthful Vibe
The Zeta looks just as beautiful as they should for the price. Of course, under $100 you can find nicely crafted alloy metal iems with unique designs. To be honest they are becoming a dime a dozen. So, what sets the Hiby Zeta apart? For one, Titanium is a solid choice for shell material. It’s much more durable than a softer metal like aluminum which we often see. Also, Titanium is much lighter than a traditional Zinc alloy which we also commonly see. Of course, this is not the first, nor will it be the last to use titanium. I think what truly sets the Zeta apart is the design language. It’s fresh, it’s flawless and it’s very high-end in appearance. More so than many other premium sets within the price point. I think the design is very well accomplished. Now, is this for everyone? Almost certainly not. The Zeta has a more youthful vibe and a flashier exterior, so I do think it is somewhat of an acquired taste.
Internals
Hiby chose to add a total of nine drivers inside of the Zeta which is a bear to tune without coherency issues as well as a number of other problems which can arise. Not only does it have nine drivers, but the Zeta is also a tribrid iem. The Zeta utilizes a 5-way electronic crossover unit, and 5-way acoustic chambers. As far as drivers… The Zeta uses Dynamic Drivers, Balanced Armatures and EST drivers. The sole Dynamic Driver used is actually a 10mm Liquid Silicone with a custom Kevlar Diaphragm. Hiby also went with four BAs in total, all made by either Knowles or Sonion. The last part I adore as Hiby decided upon four “3rd generation” Sonion EST’s. Now, Hiby crammed all of this into a shell that is not larger than any regular sized iem out there. Don’t get me wrong they’re big but they don’t appear “nine driver” big.
Fit
That was a perfect segway into the fit category. Obviously, what good is an iem if it doesn’t fit you well? Basically useless. However, I can certainly answer this question for myself. The Hiby Zeta fit like a charm. Truly, they hug my ear as though they grew there. There isn’t a jagged or rough edge on the Zeta. The comfort is very nice for me. Of course, I have zero idea how the Hiby Zeta will fit you. I found the Zeta very easy for me to get a good seal with the included tips and it didn’t take me fiddling to get them to sit right. The nozzle is medium length, not too intrusive and long and not too shallow and short. For me it’s just right. I found isolation to be fantastic once a good seal is met. Also, there isn’t a whole lot of sound leakage happening either.
Drivability
The Hiby Zeta is rated at 9 ohms, with a sensitivity of 112 dB/mw. To be completely honest and slightly joyful, the Hiby Zeta can be run off of most any source. Obviously, I don’t have a smartphone with a 4.4 balanced port but every source I tried the Zeta out on had plenty of headroom and they just felt very sensitive. This is pretty good news. Of course, 99% of the time if you have the change laying around to purchase a $1,400 iem then more than likely you have a good source to drive them with. I found the Zeta paired nicely with more resolving sources but truthfully played well off of anything. These are subjective thoughts obviously.
Turning to the IFi Go Blu for mobile purposes I found the Go Blu to have way more than enough juice on 4.4 balanced. The dynamics were great; however, this was my least enjoyable source of all. Don’t get me wrong they pair just fine but the others were simply better. The Go Blu has a warmer and lusher Cirrus Logic CS43131 dac chip, but it also has plenty of driving power. All together it sounds nice but a hair warm and less refined off of Bluetooth and LDAC.
Dongle Dacs
Using my Moondrop Dawn 4.4 which also uses the CS43131 dac chip I heard a completely different sound. The Dawn has a more rambunctious and analytical type sound which focuses more on macro-dynamics and dynamism in general. I love these two together. Using the Hidizs S9 Pro I didn’t like the sound quite as much simply due to the ES9038Q2M’s sound when paired with the Zeta. Again, it sounds awesome but simply doesn’t as clean as when pairing with the Dawn 4.4 to me.
DAPs
Moving onto some daps, I began with the Hiby R6 Pro ii and its AK4499EX + AK4191EQ dac chips. The extra power was a clear indication that the Zeta thrives off of a better source and more power given. Running off medium or high gain and using Class-A amperage. Heck even using the Class A/B amping I was more than impressed. Separation and staging simply got an audible boost and the bass clearly tightened up. It is audibly obvious that the Zeta scales to the quality of the source quite well. Of course, the R6 Pro ii is slimmer on the low end without calling it slim… perse. Still nicely tightened and clearly resolving these two seem to pair very well together.
My personal favorite way I listened to the Zeta was with the Shanling M6 Ultra, however. I was in heaven as i found the tonalities of this source and the auditory qualities of the Zeta to marry perfectly together. The M6 Ultra does have a more velvet sound yet very resolving sound without coming across too thick or veiled. Butt it’s also so very clean with great note weight and transperency. Transient attack/decay seemed so exact yet also dynamically expressive throughout. The M6 Ultra has the AK4493SEQ dac chip which does wonders paired with this set.
All you really need
Basically, the Zeta will run off of almost any source and for all intents and purposes the Zeta plays well with most sources. Perhaps some are better than others depending on your preference. I can say for sure that better sources as well as more amperage will help to bring out the best in the Zeta. However, in the end all you truly need is a good dongle dac, the better quality… well…the better. The Zeta will reward you and your ears will thank you. Of course, I wouldn’t think that anyone who would be able to purchase the Zeta would also very likely have some good sources laying around. I would assume anyways. Truly a fantastic iem.
Sound Impressions
I have been beyond impressed with the Hiby Zeta and its ability to replay my library in this all-encompassing and dynamically pleasant manner. Truly, the Zeta commands the atmosphere around my mindscape that… all attention must be paid! This is one of those iems that abound in all directions with musicality and sound. It’s wide, it’s deep, it’s tall and the sound of the Hiby Zeta is quite infectious in the most engrossing way. There’s a richness, or a fullness to the timbre which can’t go unstated. Also, there’s great articulation to the details within any track I tested with. I hear a nice combo of detailed & dynamic, lush & nuanced within this 3D soundscape. The Hiby Zeta has macro-dynamics which abound and fill the soundscape in my mind, trult a fantastic listen. Let me explain…
The Hiby Zeta sounds like a slightly warm with a U-shaped sound signature, in that the mids aren’t overly recessed (in fact somewhat forward) while the bass and treble is still well emphasized. The tonal color of the Zeta is definitely warmer with a spritz of shimmer up top. Note weight is on the thicker side throughout but mostly in the lower half of the spectrum. There is a smoother body to the sound down low with a decently rapid attack to my ears while maintaining a more atmospheric decay. The Zeta has an altogether wonderful bass region. The midrange is lush, vibrant, and musical. The treble region is very detailed, non-offensive and notes in this region are bodied and snappy. The replay as a whole is very resolving with a holographic rendering of my musical library that I haven’t heard quite like this before. I hear multiple layers with fantastic depth of field. Truly a flagship type sound.
Bass Region
The bass has a nice mix of quantity as well as maturity in my opinion. It has just enough boom and slam for my tastes. This isn’t some basshead type sound like I’ve seen reported in various places. No, this is a mature and fun sound that is prominent enough to color the sound and give off a wholly sonorous bass while also remaining kempt and clean with a bulbous leading edge and a natural decay. What I find most appealing is the smooth nature of the bass while maintaining this moist density. I find the attack to be on the softer side while there is a depth to the fundamental body of most bass notes. The harmonics in the bass region decays in a realistic way as well. There is emotion in this bass with tactility and this atmospheric unwind to the release of notes that makes instruments like percussion sound so enticing.
Sub-bass
The sub-bass comes across as pretty guttural when it needs to be. I find the sub-bass to be mildly deep but very condensed, firm and compact. The sub-bass presents a clean sound that creates an impactful and thick haptic vibration when the track demands it. Tracks like “Paradigm” by The Head and the Heart starts out as gravelly, dense and deep, which on a lesser iem will almost come across as a smeared mishmash of reverberant bass… yet with a bit of rhythm to it. On the Zeta the sound is defined, sharp, textured to the core and jarring in its resonance. Still, it is in control. Or Killer Mike’s new track “Motherless” off of his latest album which also happens to be [Motherless]. Friends, the low and thrumming sonority once the bassline commences has this droning resonance which is hypnotic on this set. You also have Killer Mike’s ridiculously fresh flowing lyrics that come across pristine over top of the beat. Man, the Zeta just nails it!
Mid-bass
The mid bass has a nicely atmospheric slam with a smoother tone overall. It’s milky friends! The mid-bass is deft and zestfully boomy when called upon. I don’t know how else to explain it. The bass slam is actually very fast and timely while still maintaining that elemental earthy decay/sustain. The bass is well adept to mimic any fast bass track with relative ease. However, in that speed is this juicy weight and smooth tonal character that’s buttery on the surface with an almost corporal mental image. So… Milky.
Very well done…
“Abracadabra” by Young Thug has this deeper bassline that undulates with separate bass beats which chime-in with a repetitive sequence. Friends… one thing is clear; the Zeta has some oomph. That’s the best way I can say. The Zeta is great for hip-hop and similar genres. In this track Young Thug sounds perfectly separated from the cover of the bass with a layered approach which sounds deep and detailed. No this isn’t some analytical type of fast bass approach. It’s more than that. The bass is still pretty quick, but the control and density are what sets this set apart. There is depth to the bass, or a roundness that encapsulates bass notes which shows up in many different scenarios. Especially with instrumentation like bass guitar and even big kick drums.
Most of my bass guitar tracks found a nice home with the Zeta. I usually jump straight to the song “Groove” by Ray Wylie Hubbard. On the Zeta this track has this tactile, juddering, and simply dirty riff that vibrates and fills the soundscape with a very clean and coarsely edged note outline, just as I’m assuming the artist and the instrument intended. Clearly there is enough mid-bass emphasis to fill out the sound without being too full and emphasized. Kick drums also sound resounding hallowed out and full and with a tacky surface texture. Bass singers like Avi Kaplan or Josh Turner sound very sonorous and heavy bodied, but also have an organic quality to their voices.
All things considered
All things considered; the bass region is the “King” attribute of the Zeta. It isn’t the world’s deepest and most dense bass, or even the most authoritative for that matter. Frankly I’m glad it isn’t. Yet I find the bass region to be unequivocally mood inducing. For example, it doesn’t matter what mood I’m in, once I hear the beat drop on “All My Life” by Lil Durk or the glassy and punchy bass drop in the track “Heatwaves” by The Glass Animals it is very easy to get wrapped up in my music. There is a saturated feeling in the low-end that still comes across layered and macro-detailed. The bass as a whole is the main emphasis when listening to the Zeta but it never comes across as a detriment to the surrounding frequencies.
Midrange
The midrange has this rather forward, or “not too recessed” presence that doesn’t have the slightest hint of veil or haze. Completely clear and clean in a warmer and smoother setting. You would think that in a heavily bass-oriented song, the rest of the mix may would be concealed a bit or masked over. Honestly, I never found this to be an issue for me. Even in these situations the midrnage still manages to be the center of attention when needed. They still manage nice note definition and a natural realism that sounds lifelike and still maintains this nicely ubiquitous and prevelant residence in the imaginary stage.
Nicely tuned midrange
Hiby knew exactly what they were doing when tuning this set. It’s a different take on what a U-shaped sound can be. I find the midrange to be melodically resolving, very polished and nicely organic and clean and they don’t need any bright rise up top to illuminate them or “bring them out”. The mids are smooth in body with decent texture at the surface.
You won’t hear anything peaky, won’t hear any sibilance, and you won’t hear any of that metallic timbre that balanced armatures can so often exude. I find the midrange to have a decently lush and musical sound which also remains pretty detailed for this type of tuning due to its great resolution and tighter transient attack and decay. Tight may be taking it too far actually. It’s more lifelike in body which comes across clean and tight I suppose. There is a lushness throughout yet warmer to a slight degree in the lower half of the midrange, while the upper half does sound more energetic with a slight shimmer.
Lower-midrange
There is a feeling of rich intimacy on the Zeta in the low-mids. They sound organic, natural and appropriately bodied. The sound down low is on the warmer side yet well resolving with a warm transparency.
“Where I find God” by Larry Fleet is an example of the Zeta’s bodied and resolute replay while fostering the capacity to sound true to life. Larry’s voice has this coarse southern drawl that sounds sharp, whetted, yet also full on the Zeta. I hear a round circle impression of his voice. There’s depth there. The modulations of his voice have an effortless cadence. Now, his voice is not exactly up-front and forward but it is very well highlighted. I would also say that even with the warmer presentation there is still a sense of openness and smooth yet airy presence, as I don’t hear any congestion at all, even listening to complicated musical arrangements.
Lower-mids cont…
Higher pitched males, closer to tenors are obviously slightly more pronounced as in the track “Morning Song” by The Avett Brothers. I hear a certain crispness to the lead singers voice along with this 3D type amplitude. I could just say “fullness” too but 3D type amplitude says it a little better. Anyways, this track sounds great on the Zeta, of course if you are into this type of music.
As you walk up the register the sound does begin to feel more lifted, airy. Almost like they begin to glow a bit more. Well, as airy and lifted as a warmish tonal character can sound. This unquestionably is not some analytical and dry sound. Even as we begin to walk into further up the midrange, the sound has a richness to it. Perhaps they slim out to the slightest degree as you listen to higher pitch males or females but always the sound has some milk to it. I would probably say that the lower-midrange is the weakness of this set for me as it is a little more fuzzy (thanks Reddit guy, you know who you are) and not as defined as the rest of the spectrum. However this is by such a slim margin that I questioned even adding it to this review.
Upper-Midrange
In my opinion females “steal the show” as far as vocals are concerned. There is a nice emphasis which adds a very clean and controlled shimmer to the sound. Samia in her song “Breathing Song” on the Zeta is a nice display of soft musicality meets strong vocal energy. There is an verve within the velvety richness of a soft female inflection on the Zeta and Samia’s vocals on this track is a proof of that. Her voice is slightly higher in octave, but the cleanliness and note body, coupled with this subtle shimmer and depth really sounds fantastic on the Zeta. Or Jess Williamson in the song “Stampede“. The emotion of the song is so well displayed, like in surround sound her voice comes across in layers amomgst the piano play and the deep bass guitar around her. Atmospheric is really a good word to describe the sound. Call it a smooth-vibrancy with sprinkled-in luster to the harmonics in this region without ever coming across harsh.
Instrumentation
Instruments in the midrange enjoy a semi-thick timbre. This is not for everyone. I for one usually gravitate to a more neutral sound, but that’s certainly not a concrete standard of mine. The Zeta is proof of that. In all honesty, I can appreciate and enjoy all sound signatures. This one happens to be a bit more on the warm side and instruments react accordingly. Instruments and voices which fundamentally reside in the midrange are generally thicker in note weight as the mid-bass spills over. There is an evident warmth to the sound that is very discernable and lucid while note outlines tend to be on the softer side. I wouldn’t call them soft in general, but they aren’t knife edged or ultra snappy. This takes nothing away from detail retrieval or resolution as there is space for separation coupled with a tighter transient attack/release. Perhaps texture takes a slight hit in the lower midrange, but it isn’t something that takes away from my music, not by any stretch of the imagination.
Instruments cont…
Strings sound springy with nice secondary harmonics and depending on the track I find it easy to recognize all the tiny details which arise from a string pull. Depending on the track of course. Bass heavy songs do tend to make this a bit more difficult but for the most part strings sound great. Percussion is lively, brisk, and has great energy to operate. Snares pang with a nice intensity and the fundamental tones of a cymbal strike are crisp and full. Piano has a mostly harmonious and melodic quality that sounds very nice too. For the most part. Again, if you are listening to a bass heavy track then everything does get drowned out a bit more. This is something to consider when purchasing.
Treble Region
Now we come to one of the better surprises for me. The treble region is taken care of by Sonion ESTs, and they sound fantastic. At first listen I didn’t notice the subtleties within the treble region. It wasn’t until I sat down in a quiet place that I was able to critically listen and catch the quality of this treble. The treble is not overly pronounced or boosted. It isn’t overcooked or overcompensated. This also is not some sparkly and tinselly treble fest of brightness and luster. This is instead a treble that awards the listener with a detailed sound, both for the finer things in their music as well as a detailed listen in the structure of the sound. Each note in the treble region has definitive structure to it. There’s a nice defined edge on most notes in this area. I could use a bit more treble punch, but I do hear an almost saturated treble. Not overly dry and not forced. Resolution is superb.
The Zeta replays an artist like Billy Strings very well, as in the track “The Fire On My Tongue“. What you have is rapid fire banjo play which moves along at breakneck speeds and the Hiby Zeta keeps up with no problem whatsoever. In fact there is an emphasis on each note as the EST drivers are doing what good EST drivers do. The treble has a nice command of the space around each treble note with a highly resolving replay. As though each note has its own atmosphere. Okay I’m going a bit too hard with that but it’s along those lines. Also, details are very easy to discern.
Safe?
The treble doesn’t come across peaky, not even in the slightest. If anything, it is more of a safe tuning. Hiby did tune the Zeta to have some shimmer but not enough to sound sparkly or lustery. I certainly don’t hear any sibilance at all, and I don’t hear anything splashy or any forced resolution. It sounds as though we are hearing a treble which leans soley on the competency of the drivers and their ability to delineate instruments in this region. I really did enjoy my time with the Zeta as I heard the treble region in a new and engrossing way.
Technicalities
Soundstage
The stage size of the Zeta is rather large and full. Above average in width, height and depth, the Zeta gives a large soundscape for my musical library. I hear a wholly 3D environment that has fantastic depth of field. Holographic in every sense with great layering of sounds. This is certainly a “pro” of the Zeta as the soundstage is full, immersive and authentic.
Separation / Imaging
Another great feature of the Zeta is its innate ability to separate elements within a stage. I was in heaven listening to this set as I could truly pick apart every instrument no matter the complexity of a track. The only time separation wasn’t an absolute walk in the park and easily discernible was when listening to bass heavy tracks or very poorly recorded track. This shouldn’t surprise anyone. The Zeta is extremely resolving in every sense of the word but some things even the Zeta cannot get around. Imaging follows suit with the Zeta’s ability to separate elements within a stage. There is a clear delineation between instrumentation and vocals as well as clear markers from left to right and front to back.
Details
The quality of these drivers that Hiby chose to use inside of the Zeta are evident and the tuning and driver quality is really awesome. Here we have a fun sound. Think about that. Bigger bass region, big macro-dynamics, immersive, rich note weight. These cues aren’t usually markers for a set with good detail retrieval. However, in the case of the Zeta you will find this set is extremely resolving. There’s more though, any set can be resolving and detailed and usually that means analytical and dry. Hiby tuned the Zeta to be that dynamic sound yet detailed enough to not miss the minutia in a track. The Zeta has this 3d type detail retrieval where all sides of an instrument can be accounted for. Harmonics from the human voice carry weight. Guitar strings ting with residual harmonics as well and about a hundred other examples. I’d say the only time you’d be harder pressed to hear tiny details is in bass heavy tracks. All in all, the Zeta has very nice details retrieval. 
Is it worth the asking price?
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