Soratune has made 2024 an emerging year for them for a rather underappreciated release of a superb dual dynamic IEM, the YI01 that is being marketed as a gaming earphones but I personally do feel that it is superb for a fun, lively listening for music. For them branching out from Letshuoer, they certainly do have the experience and for 2025 they have decided to produce a single dynamic driver banger named the BI02 and at a rather friendly asking price of sub USD70 or around RM240. It is a culmination of years of tests and trials with various engineers and producers based on their BI01 and past flagship M118. I have reached out to Soratune for a sample to review and they gladly gave us the opportunity to review this possible hidden gem. They sure do look promising on paper but how will they fare in this saturated arena of single dynamic IEMs? We shall find out here.
Functions & Specifications
Before we start the review, here are the specifications of the Soratune BI02;
- Driver Type : Single Dynamic N52 DLC Driver
- Impedance: 29Ω@1kHz
- Sensitivity: 107dB@1kHz.
- Frequency Response Range: 20Hz-20kHz.
- THD : ≤1%@1kHz
- Shell : CNC Aerospace Aluminium With Titanium Nozzle Chamber
- Isolation : 120dB
- Cable : 5N OFC Silver-Plated Cable with Standard 0.78mm 2-pin Connectors, Single-Ended 3.5mm or USB C DSP Cable (Both With Microphones)
The Soratune can be purchased now at AliExpress and through their website soon.
https://a.aliexpress.com/_oBffgaN
Packaging & Accessories
The packaging here is similar to the YI01 and they are aiming to have a minimal plastic packaging to reduce waste. The packaging does feel premium and it is packaged professionally with a simple yet classy presentation worthy of their asking price. Inside we will find 6 pairs of various sized eartips (3 pairs wide bore, 3 pairs narrow bore), a fabric rectangular hard case, a cable, some paperworks and the head unit itself.
Design
The language here is sleek, slim and simple which I am a fan of. It has a smooth matte surface and it is very lightweight indeed. Ergonomics here is superb with a medium sized over the ear design that fits most ears snugly. Finishing on these IEM is great with their neon green brand logo embossed on the faceplate. There is only 1 colour scheme available which is matte silver.
The nozzle here has a width of 5.5mm at the tip and they have a unique spiral metal mesh to prevent dust and moisture entering. Soratune has stated that the front nozzle chamber is made from titanium which gives the BI02 a clearer sound.
The BI02 is driven by a single dynamic driver that has a diamond like carbon diaphragm with N52 magnets that boast a 1.5 tesla magnetic flux. They have a dual chamber setup where the high frequency titanium chamber at the nozzle for the high frequency and a damped back chamber for deeper lows. There are 2 vents on the other side of the faceplate and no driver flux is present which usually indicates a well vented system.
The cable included does look rather simple as it is thin unlike the YI01 cable which has 4 cores twisted but the USB C plug is small and might be the smallest USB C plug I have ever encountered. The DSP here is basic but Soratune has stated that they used a high quality chipset within. Driving power here is acceptable but I do find cable rolling a recommended option for the BI02.
Gears Used for Comparisons
FiiO Q7
Hiby FC6
Questyle M15
EPZ TP35
FiiO BTR7
Dunu Luna
Dunu EST112
Soratune YI01
BQEYZ BQ10
Intime Sho DD
Rose Technica Star City 5 Pro
Intime Sho DD
Letshuoer S15
Songs list
Tone and Presentation
The tone of the BI02 has an almost W shaped sound with some sterility and warmth present that emphasizes on the low and highs but they are still very well balanced with their slightly forward midrange. They have a full bodied sound that is thickish and possess a ratjer sterile sound that has some musically in them. Technicalities here are decent with great clarity across the spectrum and details here are good with then leaning more towards the macro details rather than the micro details with no muddiness present. Dynamic range here is great with a well extended high and lows.
Soundstage
The BI02 soundstage is tuned towards a more intimate soundstage and they are not the widest nor airiest but they still have enough room to not sound boxy. Their thick sound also comes with the caveats of masking the soundstage width but in return we do get a more intimate sound that is inviting.
Separation and Timbre
Separation is average with a wide stereo sound has no incoherence and crosstalk issues as typical for a well tuned single dynamic driver setup but the separation does lack width. Timbre here is slightly bold, organic and impactful with some coloration present but still has the accuracy free of any unnatural timbre when properly paired. The BI02 is a fun and full sounding set suitable for a wide range of genres.
Drivability
Rated at 29 ohms with a 107db sensitivity, they do need some juice to perform and a powerful source will bring out the best of them by refining the higher region. The BI02 are susceptible to pick up noise on certain sources. The scalability of the BI02 is not significant but when used with a good source with ample power, they do tend to sound more refined and matching them with a warm neutral source, they will perform even better. They are forgiving in the type of files played as normal streaming or low bitrate files do sound decent and higher bitrates files do sound slightly cleaner and clearer. The BI02 does suit casual listening but serious audiophiles or engineers that listen critically might find them lacking in their sterility.
The Bass (Low)
The bass present here is actually perfect for my preference as they are meaty, authoritative when called upon and they do possess an essential dynamic bass that is well extended. The bass here has a neutral presentation with a mild lift on the mid bass that gives an energetic presentation. Details and clarity here is top notch with a tight, fast and clean slam that suits a wide range of genres without overpowering issues. Sub-bass here reaches deep and they have a decent rumble but the BI02 emphasizes the mid-bass a tad more. Basshead might yearn for a stronger rumble but the bass here is tuned more towards a natural, transparent, dynamic bass with a decent resolution.
The Mids
Midrange is a forward, thick mids leaning on the upper mids that gives them a slightly brighter sound signature. It also has a mild warmth that is lush and immersive but on some tracks, the upper midrange does pose some peaks but in a small margin. The macro details here are superb and are the dominant sound than the average micro details though it is still competent in their price range. Resolution here is good and music is presented vividly with a mild coloration for a sweeter, musical sound. Transparency is great for the asking price and music does sound accurate and natural. The BI02 vocals sound great with male or female vocals with a lush, intimate sound that is full of emotions and brilliance. Instruments do perform mostly well but on certain strings like electric guitar or violins does sound a tad harsh on the higher pitch.
The Highs
The high range present here is a neutral to flat high range that have a good presence while being smooth and inoffensive. The high range here is well extended and that gives the highs a good airy extension producing an open high range. Sparkle here is great with a mild crisp decay that gives an energetic high range but occasionally especially on cheaper bright sources, they do tend to display some unnatural timbre. Details here are superb with high notes well displayed along with great clarity. The high range here actually does borderline to a sibilant sound partly due to their upper midrange peak but it is acceptable for me as fatigue does not set in even for long listening sessions. Treble here has a mild intensity that gives a mild spicy sound that is lively without sounding too polite.
Comparisons
VS Soratune YI01
The Soratune YI01 although not very well known, they are one of my daily drivers as I do enjoy their mild V shaped sound with good technicalities. They are equipped with 2 dynamic drivers and priced similarly to the BI02. Coherence is better on the BI02 but separation does sound better on the YI01.
High range quantity goes to the BI02 with a spicier presence with better clarity but details on both are similar. YI01 albeit still has a strong high range, they are smoother and extend better.
Midrange here has a similar thick sound with a warmish tone to them. BI02 does sounds a tad brighter with better clarity and details while the YI01 sounds lusher and doesn’t possess the upper midrange peak like on the BI02. Resolution on YI01 is more vivid while transparency does sound more accurate on the BI02.
Bass quantity on the Yi01 is slightly bigger and deeper along with an extended sub-bass response. The bass slam on the BI02 is tighter, faster and has better texture along with better details.
Soundstage on the YI01 is wider by a small margin with an airier presentation while the height is similar.
VS BQEYZ BQ10
The BQEYZ BQ10 is one of the current releases from them with a friendly price that cost half of the BI02 and they are a true performer in their price range. They do have a neutral sound with a mild bass boost that punches above their asking price. Build and fit on the BI02 is better with an all metal, slim body.
Highs on the BI02 does sound brighter and slightly stronger with better energy. Sparkle is more evident on the BI02 and they are crisper. Timbre on the BQ10 does sound a little unnatural but they are smooter and extend better with more air.
Midrange of the BQ10 does sound more accurate with less coloration and has better transparency. Mids on BI02 does sound clearer but detail retrieving on both are good. The BQ10 upper midrange is smoother but brilliance on BI02 is better albeit a little harsh
Bass on the BQ10 sounds bigger but the slam is a little boomy compared to the tighter bass of the BI02. Mid-bass lift on the BI02 is more satisfying. Details and clarity does sound better on BI02 but in a small margin. Sub-bass on BQ10 dives deeper with better extension.
Soundstage on BQ10 does sound wider and a tad airer.
Synergy
The overall sound of the Soratune BI02 is leaning towards a bright sound and with their upper mids peak, I do find the BI02 matches well with warmer or neutral sources. They are easy to drive but on balanced sources I do find their separation and soundstage increased by quite a bit. Their forgiving nature does mean that they will sound great even with bluetooth sources and streaming.
Good synergy
FiiO BTR7, EPZ TP35, Hiby FC6, Hidizs S8 Pro, Questyle M15
Not so good synergy
FiiO Q7, FiiO KA3, Hidizs S9 Pro, Qudelix T71, EPZ TP30
Who Is It For?
The Soratune BI02 is a recommended product for those who want a musical IEM with a bright-ish sound. They are a good vocal performer especially with female vocals and they are an intimate set. They are suitable for those who listen critically and for light monitoring but also suitable for daily casual usage. Bassheads will yearn for a bigger rumble but treble heads will find the BI02 quite appealing for their energetic highs. Genres like EDM, pop, hip-hop, rock are recommended but not so much for metal and Jpop as they might come off as a little peaky.
Final words
Soratune while still an emerging brand in the audiophile scene, they indeed are heading in the right direction. With the successful release of the YI01, the BI02 is a great sidegrade that offers a more musical and mature tuning that has better technicalities. They do sound great with a neutral sound that has the energy but they are up against a bunch of competitors in this price range. They do need some refinements in the upper midrange but their solid build quality, tuning and amazing ergonomics is undeniable showcasing a well made product that is worthy of their asking price. I really hope to see Soratune come out more with amazing products in the near future as their enthusiasm is special.
I would rate this product a 4 over 5 stars.
Pros
- Decent technicalities
- Solid build with good finishing
- Well tuned dynamic driver
- Simple yet classy design
- Great ergonomic fit
- Sterile without being too polite
- Good overall details and clarity
- Natural timbre, accurate sound
- Superb dynamic range
- Textured, fast, solid bass
- Good mid-bass lift
- Thick, intimate midrange
- Energetic, extended high range
- Great resolution and transparency
Cons
- DSP cable doesn’t bring out the best of the BI02
- A little shouty and splashy at the higher midrange
- Sub-bass impact a little low
- Some minor colouration present
- Up with stiff competition in this price range
- Mediocre separation
- Soundstage more on the intimate side
- Need some power and good matching to perform
