Fit and Comfort

There are subtle fit differences between the different ear tips of the same size included with the HiBy Lasya. It's hard to see on the camera front-on, however, so I am only showing an example with the size M black bore "balanced" silicone tip installed on the right ear bud and inserted into an artificial ear mold. I have average-sized ears, and the ear mold above represents my own experiences well enough as a proxy. Size M silicone tips are my go-to for testing since foam tips are not included by some, and in this case, the black bore silicone tips worked best not just in terms of a good, secure fit with decent passive isolation, but the bore and flange combination making for a more balanced sound signature than the other two silicone tips, via placebo or otherwise. Also note how well these IEMs fit that anthropomorphic pinna! I wish I could say the same about my own ears, but the thickness of the shells is all that's keeping these from being a perfect fit. The ridge on the top is not going into my concha spiral since the shells jut out a bit too much for that. The aggressive sloping on the inside helps to an extent, but your mileage may vary when it comes to how well these fit even assuming you have medium-sized ears. Smaller ears may struggle more. That having been said, the gentle curves and smooth exterior may still prevent these from just coming off inadvertently, as will the pre-formed ear hooks on the cable adding further support. Positioning of the cable plugs with the hooks is also well-executed; I will give HiBy props for getting all of these factors right for most end users. The resin shells are light, and the IEMs weigh ~4.6 g each, preventing physical fatigue over time. Passive isolation will depend on the fit you get, and I ended up with above average seal and isolation.

Audio Performance

Audio Hardware

In addition to the basic minimum of confirming that this is a single dynamic driver setup with a dome and diaphragm, voice coil, and associated magnets moving it back and forth to generate sound, HiBy provides some interesting details about the driver in the Lasya. The product page may have you think the entire diaphragm consists of carbon nanotubes, especially with the added note about them being 10 nm long and arranged on a plane. Problem is that unless this is a buckypaper out of aligned CNTs, which would cost a ton, having a CNT-only diaphragm that is rigid, durable, and durable just isn't feasible. I am inclined to say this is another case of a coating on top of a base diaphragm, be it mylar or aluminium. The driver diaphragm is 10 mm large, which is about average for single dynamic driver IEMs. No details about the voice coil or magnets are provided, but HiBy mentions the internal wiring is not compromised as OCC copper is used, and the gold-silver alloy solder will help eliminate electrical conduction bottlenecks while appealing to those special audiophiles who think solder will influence the sound signature. The drivers are part of the acoustic chamber assembly, with the shells having an integrated convective air intake and exhaust system as opposed to dedicated vent holes, which helps prevent pressure buildup in the ears and reduces the potential for driver flex. This makes for a set of IEMs that is fairly easy to drive with a slightly above average rated impedance of 32 Ω and sensitivity of 108 dB/mW. Purely by numbers, the Lasya is easily handled by even a basic USB Type-C dongle. The HiBy Lasya is just fine with mobile devices thus, and going with a portable Bluetooth option such as the ones we have covered before also makes this a wireless solution. The lack of a 3.5 mm audio jack for most phones these days is another reason to consider a DAC/amp or even DAP for portable use. If not on the go, space is less of an issue, but the relatively short cable might still be a potential handicap if using a PC as the audio source.

Frequency Measurement and Listening

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


Our reproducible testing methodology begins with a calibrated IEC711 audio coupler/artificial ear IEMs can feed into enough for decent isolation. The audio coupler feeds into a USB sound card, which in turn goes to a laptop that has ARTA and REW running and the earphones connected to the laptop through the sound card. 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, which nets a good balance of detail and noise not being identified as useful data. Also, the default tuning was used for testing, and no app-based settings were chosen unless specifically mentioned. Each sample of interest is tested thrice with separate mounts to account for any fit issues, and an average is taken of the three individual measurements for statistical accuracy. For IEMs, I am also using the appropriate ear mold fitted to the audio coupler for a separate test to compare how the IEMs fare when installed in a pinna geometry instead of just the audio coupler. The raw data is then exported from REW and plotted in OriginPro for easier comparison.


The IEC711 is such that you can't really compare these results with most other test setups, especially those using a head and torso simulator (HATS). The raw dB numbers are also quite contingent on the set volume, gain levels, and sensitivity of the system. What is more useful information is how the left and right channels work across the rated frequency response in the HiBy Lasya. The left channel was separately tested from the right one, and colored differently for contrast. I did my best to ensure an identical fit for both inside the IEC711 orifice, so note how the two channels are very similar across the entire useful 20 Hz to 20 kHz range. HiBy markets a channel balance tolerance of <2 dB, which we are easily within here. In practice, I did not notice any channel imbalance, and this also ends up being a substitute for quality control testing with a sample set of two drivers that are potentially channel matched. Measurements taken after 30 hours of testing, which included these playing a mix of various songs as well as white or pink noise and sine sweeps, showed no difference. There was no perceived burn-in effect thus, and none was measurable, either. The response with the anthropomorphic pinna in place matches the ideal scenario in the coupler almost perfectly, which is also an indicator of how good the seal was when installed in the artificial pinna.


This is the average frequency response for both channels of the HiBy Lasya plotted against my personal target taken from VSG.squig.link, which also gives you an idea of my personal preferences to better correlate any possible biases. The tuning of a set of headphones or earphones does not have to match my target as long as it is tuned with some direction, makes sense, and is executed well. After all, no one set will appeal to everyone, and having different options is what makes this hobby so interesting and hard to quantify. HiBy markets the Lasya predominantly for vocals, and female vocals at that, which is indicative of a set with some upper mids emphasis, as well as forward-facing, central vocals taking precedence over instruments. While not an approach to my tastes, I did like the Lasya tuning more than I thought.

I would classify the HiBy Lasya as a mostly neutral set with a bass boost and touch of brightness in the upper mids, and I had to have a look at the Tripowin Olina to see whether these use the same drivers or not! Tuning and characteristics are certainly similar, but I would give the edge to the Lasya in everything but the bass response. Despite the ~6.5 dB bass boost from the mids, I would not say the dynamic driver in the HiBy Lasya is very dynamic. This is a case of HiBy potentially remaining conservative since there is room for EQ—think 3–5 dB easily. So do EQ these if you want a thumpier bass response without distortion getting in the way. The stock tuning promotes the appreciation of bass guitars more, which worked well with Dua Lipa's "Don't Start Now," as I chose her latest album, among others, to test the female vocal marketing claim. EQ will help those who prefer electronic music and heavy metal, but there are arguably better sets for those music genres.

Vocals generally fare very well on the HiBy Lasya, be it male or female. Lemmy's guttural voice in "Ace of Spades" showed that the Lasya is not a one-trick pony either, as it works equally well with the likes of deeper baritones and peaky shrieks in opera music. Well, maybe not so much the latter since it does get bright and nasal-sounding with some female vocals. This set will be fine if you are a fan of higher-pitched vocals, but I did wince a couple of times with Kpop and Jpop. Imaging is spot on though, and in a wider cone around the left and right channels than many other IEMs in the price range. Soundstage, on the other hand, feels more intimate, although I admittedly have not tried the other tips as much as the balanced ones with the Lasya. Instrument separation is excellent too, which helps with layered pieces involving guitars and drums. It's not a particularly fast set, so notes decay a touch slower than I'd like, which can be felt with fast drum pieces in particular, where kick drums and hi hats feel convoluted.

The upper mids and lower treble carry on the brighter signature, and the Lasya can exaggerate sibilance present in tracks. The 4–5 kHz peak also feels more annoying in the context of things, but I would not say the set is fatiguing. Still, the upper frequencies is where EQ is touch and go and stock tuning matters more. With that in mind, the Lasya does the job well enough for classical music too, especially with piano and string instrument-centric pieces. Timbre feels natural with strings plucked neither plasticky or metallic. The in-ear resonance will be felt anywhere from 7–9 kHz based on the fit you have, so I hesitate to really say much more about the treble region since it is so fit dependent. A good fit and seal will make this a set you will grow to love for multiple different music genres; without a good fit, it may well be relegated to the IEM drawer or even sent back for a refund.

Comparisons

These days, there are so many excellent single dynamic driver IEMs in the price range of the HiBy Lasya! I had to compare it against my personal favorite, the MOONDROP KATO, which is similarly tuned but more dynamic in the lows and not as harsh in the upper mids. But the Lasya does have the edge when it comes to accessories, fit, which depends on the user, and multiple color options. The Tanchjim New Hana is far more V-shaped and inherently provides deeper bass, but doesn't handle vocals as well as the Lasya. It's quite a looker though, and I might do a quick look article to show it off. The 7Hz Eternal is the most expensive of the lot here, coming in at even more than the DUNU FALCON PRO I omitted given its mid-bass emphasized tuning is so different from the others, and it is the biggest offender in pretty much all regards. So of the four here, I'd give the slight edge to the KATO overall, with the Lasya taking a solid second place.


But then came the planar IEMs, and there seems to be a flood of these larger 14.x mm full-range planar IEMs in the same price range as of late. It started with the impressive 7Hz Timeless, which again is more dynamic and a better fit for bass heads than the Lasya, but has been subject to some quality control issues and silent revisions off late that leave a question mark hanging over it, and it certainly has the poorer treble response to where I'd personally take the Lasya over it. The Raptgo Hook-X is technically a hybrid set, but the planar driver is responsible for the tuning, and the PZT adds extra sparkle through the mids and highs. This is tougher competition, but the open-back HOOK-X makes for a complementary set more than a replacement to this closed-back set. The two sound very different in practice, so I would say pick the Lasya for vocals and Hook-X for instruments. The TinHiFi P1 Max (review coming soon) is the dark horse out of nowhere with near-identical tuning. However, it is more muted in the upper mids and treble while still being detailed. The issue is that the bass response, at least before EQ, feels even more wanting than on the Lasya. This effects the lower mids too, and it's now a case of whether you're willing to EQ or not, with EQ favoring the HiBy Lasya.