DISCLAIMER
The HiBy Crystal6 II is a tour unit. It will be sent on to the next tour participant after this review.
The Crystal6 II can be obtained here:
https://store.hiby.com/products/hiby-crystal-6-ii (no affliate links).
SPECIFICATIONS
- Driver configuration: 6 Balance Armature (BA) Sonion drivers
- Frequency response: 20 Hz โ 20000 Hz
- Impedance: 58.5 Ohms
- Sensitivity: 110 dB (no units provided)
- Cable: 2-pin, 0.78 mm, 4 core OCC copper cable
- Plug: modular options for 4.4 mm and 3.5 mm terminations
- Tested at $349 USD
ACCESSORIES
Other than the IEM, these are included:
- 3 pairs of "Crisp" silicone ear tips (S, M, L)
- 3 pairs of "Balanced" silicone ear tips (S, M, L)
- 3 pairs of "Bass" silicone ear tips (S, M, L)
- Carrying case
- 4.4 mm and 3.5 mm modular plugs
- Cable
- Carabiner
Accessories are decent enough for a midFI pair of IEMs, save for the omission of foam tips and perhaps a cleaning tool
3 types of silicone tips are included here.
The "Crisp" tips have the widest bore and boost treble and increase soundstage, though they may cause sibilance. The "Bass" tips as per their namesake are the narrowest in bore, and boost bass (though with a smaller soundstage). The "Balanced" tips are a mid-point of the above two in sonics.
The stock cable is an OCC copper cable. It is braided well, with a chin cinch. There's slight microphonics unfortunately. It has 4.4 mm (balanced) and 3.5 mm (single-ended) terminations, so the Crystal6 II can be paired with most sources other than 2.5 mm ones (no biggie if you have a 4.4 mm - 2.5 mm adapter).
The right cable terminal has a red band to delineate the sides, and I'm glad it is a gold-plated 2-pin connector rather than MMCX, which may be more fragile with repeated cable changes.
The added clamshell semi-rigid zipper case is quite nifty. The innards are lined with a soft bubble pack like material to cushion the contents. The carabiner may be useful to hang the case on the go.
The rest of this review was done with the stock cable and stock "balanced" stock tips. No aftermarket accessories were used, so as not to add any confounders to the sound.
BUILD/COMFORT
Each housing is 3D-printed via HeyGears using quality epoxy resin, with HiBy marketing that each faceplate is custom painted and polished, using a sand and hand painting technique. Hence, each earpiece is supposedly unique!
The shells are very ergonomic and light at 54g apiece. HiBy says they made the shells via 3D scans of thousands of ears, and I concur, with no comfort issues to report on my end.
There's a "R" and "L" lettering to delineate the sides.
HiBy has used a special vented architecture to assist with bass tuning and to relief pressure in the ears. Verily, I did not experience any driver flex with the Crystal6 II due to this, but unfortunately isolation is below average in view of the vents.
There's a nozzle cover over each nozzle to prevent debris and wax from falling in.
INTERNALS
Utilizing a gold-traced crossover board with a 3 way crossover implementation, the Crystal6 II utilize Sonion drivers in the following configuration:
- Custom 39AY dual-woofer LFE for the bass
- Custom 1006 dual BAs for the midrange
- Custom E50DT dual-tweeters for the treble
DRIVABILITY
I tested the HiBy Crystal6 II with:
- Apple dongle
- Colorfly CDA M1 DAC/AMP dongle
- Creative Sound Blaster X5
- E1DA DAC/AMP dongle
- Hiby R3 Pro Saber 2022 DAP
- Khadas Tone Board -> Schiit Asgard 3 amp
- Khadas Tone Board -> Topping L30 amp
- Questyle M15 DAC/AMP dongle
- Sony Walkman NW A-55 DAP (Walkman One WM1Z Plus v2 Mod)
- Sony Walkman NW A-55 DAP (Walkman One Neutral Mod)
- Sony Walkman NW WM1A DAP (Walkman One WM1Z Plus v2 Mod)
- Smartphone
The Crystal6 II is relatively easy to drive, you can probably get away without amplification, though this IEM scales slightly with juice.
SOUND & TECHNICALITIES
Graph of the Crystal6 II using a IEC711 compliant coupler. 8 kHz area is a coupler artefact peak.
Tonally, the Crystal6 II is neutral bright and a treblehead's best friend. It is thin in note weight with a sterile/analytical signature.
Technicalities are top-notch. Imaging, clarity, detailing and instrument separation are very competitive at its price range. Soundstage is average in width, but has quite decent depth/height. Transients are lighting fast.
Packing 6 BAs, unfortunately BA
timbre rears its ugly head, and vocals sound nasal, with acoustic instruments sounding a bit metallic.
Bass is focused mostly at the mid-bass, and is just slightly north of neutral in quantity. Bass extension is not the deepest in the sub-bass. Despite having a vented BA bass, unfortunately like most other BA bass IEMs, the Crystal6 II suffers from a lack of decay and "movement of air" in the bass, causing it to sound not as organic as DD bass.
Bass quality is where the Crystal6 II redeems itself. The Crystal6 II has stellar bass texturing and speed, with zero mid-bass bleed. Bass lines are easily picked out in complex bass riffs, it is very fast and clean.
The
midrange is a tinge recessed in the lower mids, with no mid-bass bleed to eat into this area. This translates into a very transparent and clear midrange. With the aforementioned good technical chops, this allows vocals and instruments to be layered well on a black background. Crystal clear is definitely a good name for the Crystal6 II!
Thereafter, there is quite a zealous 11 dB pinna gain in the upper mids. This unfortunately adds shout, and the Crystal6 II can be harsh, especially at louder volumes (Fletcher Munson curve). It is best played at soft to moderate volumes to counteract this.
The lower
treble has another peak at the 5 kHz region, which is a double edged sword - great clarity and resolution is added, though at the expense of fatigue for treble sensitive folk. Sadly, sibilance is also present.
The treble extends pretty well, giving good air and sparkle, and the Crystal6 II will be a suitable pair for trebleheads.
COMPARISONS
Comparisons were made with other midFI pure BA IEMs. Planars, hybrids and single DDs and other driver types were left out of the equation as the different transducers have their pros and cons.
Kiwi Ears Orchestra Lite
The Orchestra Lite is warm neutral. The Orchestra Lite has more subbass, but a tamer upper mids/treble region, and is very smooth and less fatiguing in contrast.
The Orchestra Lite has weaker technicalities, though it has a thicker note weight and a more natural timbre.
Audiosense T800
The T800 is an 8 Knowles BA setup which is tuned to a mildly bright V-shape. The T800 has more bass, and the bass is vented, giving a decay/movement of air that is similar to a DD bass IEM.
The T800 is quite boosted in the treble/upper mids too, but the big bass on tap gives tonal balance, even though the T800 still lies on the brighter side of the equation. The T800 has a slightly thicker note weight, and technicalities are probably a hair better on the Crystal6 II when it comes to imaging, instrument separation and clarity, though the T800 has superior soundstage.
The T800 has much better passive isolation at almost 30 dB, and is also build of resin (though it has an MMCX connector).
CONCLUSIONS
The Crystal6 II lives up to its namesake in bringing a crystal clear soundscape to the table. Resolution is great, technicalities are all-round excellent, with a very fast and clean bass. If clarity is your priority in music, the Crystal6 II is the one for you.
There's nothing to complain about the build, comfort and accessories too.
Unfortunately, the Crystal6 II has BA timbre, and will not be compatible for high volume listeners or for our treble sensitive brethren, due to the augmented upper mids/lower treble. Sibilance is also a relevant critique, though perhaps one can use EQ or foam tips or a warmer source to salvage this area. Those who yearn for a lush or analoguish style tuning may also need to look elsewhere, as the Crystal6 II lies on the sterile side of the equation.
If you are a treblehead or analytical head, and want a pair for critical listening, definitely consider the Crystal6 II in the conversation, though the above caveats will apply if you are sensitive to treble.
Kinda annoying how companies like HiBy can get achieve great technical performance but not good tuning. Others can achieve great tuning, but not technical performance. Getting both requires an arm and a leg.