BQEYZ Summer


Previously known as sub30
I'M A BELIEVER... of cables, that is
Pros: Inoffensively-tuned W-shaped IEM
Beautiful 8-core SPC, single crystal copper cable
Satisfying mid-bass kick
Midrange and treble speed and control
Natural vocal presentation
Soundstage, imaging, and separation
Comfortable and light resin shell - well-vented and non-isolating
Stock tips selection and included case
Cons: Lack of sub-bass rumble
Bass decay and slight bleed in EDM drops
Lack of air and brilliance
Lack of upper midrange bite
These issues are found with the stock cable… GET THE TRN T2 CABLE!!!!

I would like to thank Ms. Elle Zhou and BQEYZ for providing a review unit of the Summer. Rest assured that my impressions written in this review are my own personal thoughts and opinions and in no way influenced by outside parties.

I am not an expert in this hobby nor claim to be an audiophile. I just love listening to music and am fond of writing articles.


BQEYZ. Best Quality Earphone for You, Zhou (family name of tuner/owner). They’re one of the rare Chi-Fi companies that dedicate time-and-effort for each product that they produce, prioritizing “Research & Development” unlike other companies that release IEMs each and every month for the whole year. Their pace for releasing new products is about 1-2 new IEMs a year. I praise BQEYZ as a company for this act which goes to show that they put first and foremost the satisfaction that their quality IEMs will bring to their customers ahead of other goals. The BQEYZ Summer, a tri-brid IEM with a 13mm coaxial DD, custom BA unit (2nd generation), and a 5-layer piezoelectric driver, all for 129 USD. It is available in black (closer to violet) and blue (like sky), with options for either a 2.5mm, 3.5mm, or 4.4mm stock cable (0.78mm, 2-pin). This is the “second act” of the BQEYZ Seasons series, following the Spring 1 & 2. Will the BQEYZ Summer bring forth warmth to the hearts of its listeners or will it just be too hot to handle?

These were plugged to my iPhone 5s with the SD01 amplifier for the review. As per Ms. Elle Zhou, the Summer is easy-to-drive at 32 ohms of impedance with a sensitivity of 107 dB. I can happily say that this is true and a typical phone should be enough for the listener to enjoy the Summer with 1 Vrms @ 32 ohm and headroom to go louder, though even a cheap external amplifier like the SD01 brings slight improvements to the SQ.



Build and Comfort: Two-piece resin (faceplate & body). It’s light yet feels solid on hand. I got mine in the black colorway, which is closer to violet, really. It’s hard to capture in pictures, but the faceplate has some sort of glittery stuff in it. Pictures don’t really capture it’s beauty, as it’s very captivating in real life. Size is “normal” and shouldn’t be a problem for most ears (has a fin, to note). Nozzle (on the bigger side) is angled and is of the shallow-fitting type for my ear, thus it does not provide the best passive isolation. It also has a total of three vents, so yep… isolation bye-bye. A big pro for me, personally speaking as I prefer non-isolating pairs and value awareness of my surroundings.



Package: Two sets of tips (3 pairs each). Paperwork. QC certificate. Hard case (BQEYZ-branded). Cleaning brush. 8-core cable advertised as SPC, single-crystal copper.

Now, onto sound:

For this review, the IEM was left in stock mode, without mods other than going two-sizes up than usual with the clear, blue stem tips. I don’t prefer the grey tips as they have too relaxed midrange and treble for me. The clear tips have punchier bass and bring more presence to the midrange and treble region.

I can’t emphasize enough that this review was done in stock form. I included a part in the end concerning the changes I made which may “trigger” a few people.




Of the warmer side, with minimal sub-bass, having a satisfying weight to kicks and a slight bleed in EDM drops.

“Lovely by candid!” - If I were to rate the three main regions according to emphasis/quantity based on my hearing, the bass region would place 1st. Starting at 2:22 is the relatively short bass solo of the track, it leans toward the warmer side, mid-bass emphasis, with fast attack and moderate decay. This bass quality isn’t like what you’d get in a V-shaped tuning that is tight, punchy, and consuming. This is more of the “I just wanna sit down and relax in the sunny, summer morning” type of bass.

If you’re looking for skull-rattling bass, kindly look elsewhere. Testing with “Billie Eilish – bad guy” and you’ll get where I’m coming from. It stays controlled (read: no wobble or boominess to it) but it doesn’t provide the satisfying quantity of the sub-bass region to “feel” the rumble at the 2:31 mark. The good thing is that this tuning provides a fatigue-free listen.


For a bit of J-Pop, we have The Peggies with “Fortune.” Throughout the whole song, the bass guitar is very much present with my personal favorite bass lines in a song. Listening with the Summer and it sways toward the thicker side of things and though it has a satisfying body and is never monotonous, the decay speed and the warm aspect of the Summer limits its potential and hides texture.


Same case with Bad Ideas by Tessa Violet. The verse at 1:15 is associated with a bass line, and while still defined and shows a bit of texture, makes me want faster decay.


The midrange of the BQEYZ Summer is characterized by a relatively relaxed upper midrange, with vocals being presented in a natural and clear manner with a bit of warmth to it, weighty note delivery, and non-existence of sibilance even in badly-recorded tracks. Jacob Collier’s voice sounds amazing in these. Rhythm guitars have really nice heft, though the lead guitar leaves me wanting for more aggressiveness/bite and presence. I can go at least 9 hours straight without experiencing ear fatigue thanks to the tuning at my normal listening volume (low-medium). There was a moment where I even fell asleep while listening to the Summer without noticing 😝.

In an acoustic and female vocal-heavy song like “Words Ain’t Enough by Tessa Violet/chloe moriondo,” the guitar sounds like it’s made of mahogany – warm and full-bodied. I do have one gripe though. Due to the relatively relaxed upper midrange and bass quality/quantity, Tessa’s voice sounds a bit too smooth for my liking, but nothing extreme like say lacking energy. This will fall down to personal preference.


A bit of 2021 quarantine music with Jensen McRae’s Immune. Same with other female vocals using the BQEYZ Summer, there’s no thinness and is smooth-sounding. At 1:18 with the percussion playing, it’s a surreal experience to physically feel how hard it is being hit behind your right ear.


I feel like male vocals benefit more with the tuning of the Summer. For example, in The Honeysticks – Out Like A Light, Ricky Montgomery’s song is satisfyingly weighty and full-bodied. However, there is noticeable recession of male vocals but isn’t a problem with female vocals.


Treble is tuned like it’s a-step-and-a-half away from being considered bright. There is no pierce or peakiness in ear heard, for me. It is also very fast, controlled and has enough sparkle and presence for a musical experience. I would’ve wanted more “air” and “brilliance” with the piezo driver but I guess that wouldn’t have fit the “Summer” theme? Weirdest region of the Summer, as sometimes it sounds relaxed, while other times it’s very energetic.

With Blossom Calderone’s 1964, at the chorus starting 0:49 the hi-hat strikes aren’t offensive and is quite soft with a pleasant decay and a nice rattle. Ride also leans toward the softer side of things at 2:36. Crash cymbals stay fairly controlled but sound quite dull, for lack of a better word.


Continuing the tuning of the piezo driver, in “Begin Again – Tippy Balady,” at 2:00, the slow, multiple bells ringing at the same time is hyper-realistic (reminds me of Christmas for some reason) with the tambourine playing in the background. The upper midrange/lower treble tuning allows for it to not sound thin while still having the technical prowess one would expect of a piezo (from what I’ve read, that is. But the highs is definitely technically better than any DD I’ve heard).


As J-Pop is one of my favorite genres, here’s Omoibito by Ryokuoushoku Shakai. With the last chorus up to outro starting at 3:55, crash cymbals have the “energy” as it should and stays controlled with a rather fast attack and decay. Again, a-step-and-a-half away from being bright.



This is the first IEM I’ve listened to that has a driver type other than a dynamic. No metallic midrange whatsoever and strings don’t sound weird for me.

Soundstage, Imaging, and Separation: One of the best aspects of the Summer. No dimension is lacking, and with the accurate imaging and excellent separation, it can handle any track not named EDM (due to the bleed and decay) 🤣 ichikoro’s Q never sounded congested and instruments had a place of their own and never went over each other.

Detail-retrieval: With the IEM not being tuned to be analytical and having emphasized bass, the good thing is that you still hear detail thanks to the speed of the BA and piezo handling the midrange and treble respectively. For example, in MCR’s Welcome to the Black Parade intro, there’s a very subtle ticking clock that is heard with the Summer. However, in other songs, the bass decay counters this quality of the Summer. Detail-retrieval would be track-dependent to show full potential of the BA and piezo. The good thing is that I don’t usually listen to EDM and bass-heavy tracks 😏


This next part is important as this changes the Summer from 4/5 to a 5/5. Rated it at 4.5/5 for this review as the average of the scores. CAUTION: Not for everyone! TRIGGER WARNING IN 3, 2, 1…

I am a recently converted cable believer. Changed cable to the TRN T2 and oh boy was it nice!

Summer on stock cable - bass quality would have been good if not for the decay speed and mid-bass bleed. Midrange, particularly lower midrange is recessed. Upper midrange meanwhile is too relaxed and thus lacks presence in some tracks. Treble's too safe, rolls off hard, and lacks air and brilliance, for my taste.

Summer on TRN T2 cable – bass is now “perfect” with faster decay speed and is much tighter resulting in more texture heard and elimination of bleed. Mid-bass also lessened in quantity by a notch. Extension, for bass and treble also improves (FINALLY SOME RUMBLE!!!). Vocal region is brought up and male and female vocals now sound more balanced, without noticeable recession or forwardness. Due to the improvements, treble now has more presence, sparkle, and air. Not a lot of improvement in technicalities other than soundstage width (read: wider) and detail due to the faster bass response. Overall sound is noticeably more energetic compared to with the stock cable.

Might sound like snake oil for certain individuals, but I just can’t deny what I heard. The TRN T2 is a 7 USD cable which I got for less than 3.50 USD with the help of vouchers and coins (Shopee). Wouldn’t hurt to try for those in this hobby and for people delving in the sub-200 USD price range.


When I approached Ms. Elle Zhou regarding a review unit of a BQEYZ product, I told her that I would be delighted to try out the KC2, which has seen a resurgence in hype among multiple FB communities, lauded as arguably the best price-to-performance IEM under 40 USD, competing with 100 USD IEMs. The BQEYZ Summer sounds like a solid, all-mahogany, dreadnought, acoustic guitar – pleasing, inoffensive, and full-bodied. Makes sense as this accurately represents the season it was named after. The Summer would have been a perfectly tuned IEM in a sense if it had faster bass decay, more upper midrange presence, and a bit more air on top. Good thing there’s the TRN T2 cable for that 😉

****If you have other questions/concerns with the IEM mentioned, feel free to message me****​
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ASR never see cables measuring differently
Those are full-size cables.
BQEYZ Summer: Hot, Cozy It Up Tonality
Pros: - Easy to drive even to decent sources.

- Impactful and authoritative bass.

- A lightweight, High quality resin shell that fits comfortably and offers good isolation.

- Superb dynamic tonal bass quality.

- Quantity Soundstage, Quality Imaging.

- It has a high quality stock cable.
Cons: - Looks cheap to someone on first impression. ("Looks like a FH3 but in a cheap plastic shell")

- Limited colour scheme options to choose from.

- BQEYZ Spring 1 and 2 fans might find its mids and treble quality were somehow subdued and underwhelming on their liking. **

- Midcentrics will be probably to look somewhere else as they will feel some lacking on texture and less note density on mids frequency.**

- If you are a BQEYZ fan who loves their premium built CNC- milled aluminium shells on their IEM then this will be quite a shocking to you.
Hello mates and welcome to another review of an IEM that I've been interested and looking forward since it was announced a few weeks ago. I know that you are familar about BQEYZ products in Head-fi as I review their previous offerings like the resurgent popularity of their good old KC2 and their widely acclaimed Spring 2 as I give them a positive rating and highly regarded on their product offerings due to their build quality and mature audiophiliac tuning. As I have patiently waiting the release of this particular product from them and now I have obtain it and very excited to use them and listen to some of my favourite tracks. Now that I will share some of my subjective insights on this product.


I'm here proudly to introduce their latest product, The BQEYZ Summer. As we know that their previous series were named after a type of season which is Spring and now we have the Summer. It seems that they do name their flagship product line based on seasons, maybe we will expect a Winter or Autumn on their upcoming, future products. We know that BQEYZ is a well-respected Chi-fi brand that gain a good reputation and admiration from audio enthusiast forums due their build quality, a different approach on their implementation of driver in their product like tri-brid which is unusual and very few Chi-fi companies implement them and you can only find them on from top-of-the-line audio brands and outstanding mature tuning but I digress.


Anyways, let's go back to BQEYZ Summer IEM, This set is tri-brid driver consists of their custom BA, a new 13mm DD tech consists of polyurethane (PU) diaphragm and liquid crystal polymer (LCP) film and a new improved 5-layered Piezoelectric driver. This set-up is also found on its previous predecessors like Spring 1 and Spring 2 but this one is tune differently compare to its Spring cousins.
The new 13mm DD is quite interesting as these new material promises a faster bass transient, reduces excess vibration, improving signal process fidelity to be more sound natural and dynamic on both lows and mids, better rigid structural yet less weight. Then the custom BA by BQEYZ and the Piezo are both working in tandem to deliver a transparent, bright, cleaner responses on upper mids and treble. The current price offering of BQEYZ Summer is US$ 129.00 in online stores.


The Summer IEM shell is made of translucent and opaque high quality resin with some small amount of glitters that is robust yet very light. This is the lightest and less chunky shell among the BQEYZ products which is quite suprising on their decision to go in this direction, from premium looking, thick-shelled CNC-milled aluminium to feather weighted, minimalist design resin shell. This IEM has two colour options to choose from, the smoky black one and light blue one. The nozzle of this IEM has average length made of silver coloured brass and its fitting is deep enough and it is very cosy and comfortable to my ears as it sealed well on the outer ear canal which benefit for slight better sound isolation from external noise in the surrounding. As I observe this IEM, I found that it has a 3 pinhole-size vents on it for releasing air pressure from the inside.


The packaging of The Summer comes with medium-size, grayish sky blue cardboard box with small print of BQEYZ in top-left and a medium-size print "Summer" at the center. The contents inside are a pair of the IEMs, a high quality 8-core single crystal SPC white cable, 6 pairs of black and white silicon eartips in three standard sizes and all them are atmospheric eartips that you will found from their previous flagships ( The metal plate eartips organizer is not there anymore), a medium-size grey IEM leatherette case ( quite a downsize from Spring 2's leatherette case), a small brush for cleaning the nozzles, a velcro cable cable lace and some paperworks like warranty card and simple instruction manual.


The stock cable of Summer feels very premium to touch as it is very supple and soft in my hand. It doesnt entangled and very sturdy for daily usage and longevity.


The scalability of the Summer is very easy to drive and adequate enough as it has an average impedance rating of 32Ω and high sensitivity rating that can be driven through low powered source such as smartphones, tablets, PC and laptop though it will be more benefited on high quality hi-fi DACs and amp as it will show its true potential.


The Summer has balanced, mild U-shape tonality with elevated and enhanced bass , balanced to linear mids and some lift and emphasis in treble.


And now, I'll describe the sound characteristics of each audio frequency range based on my hearing perception.


I describe the bass of this one as very punchy and has well-defined power. It has precision, impact and intensity as it reveal the depth extension on its sub-bass which shows ardently slam and definitive roll and rumble. The midbass quantity has a thick density as it is still sounds balanced as it tends to avoid on being overly excessive that it might bleed on the mids. The bass kicks sounds life-like, pounding and sustaining while bass guitar sounds attested to its tune as it show its broady and resonant nature especially on fretless, tapping, slapping and picking techniques in rock and metal tracks. Bassheads will definitely love the bass quality of this one as it engaging and impactful.


The mids are slightly recess on this one but it is still deliver a forward, clean and still retain its linearity with some warmth on it. The texture density of vocals are on average quantity as both male and female will have different outcome based on their vocal range capacity. The male vocals are a little bit overshadowed compare to the females as the latter taken the advantage technicality due to some emphasis on the upper mids. The male vocals are more on a leaner side and in between or eclipsed in some tracks that percussive and rhythm instruments are more prominent but still retains its resolving details and clarity that harmoniously mix well on the track. The female vocals are more lively and transparent as it show more details and etherealness in the mix. I feel the particularity of high octave vocal range as sonorous and resounding. The rhythm and percussions instrument are even more eminent and distinguishable as I feel the snares hits very intimate and natural. The guitars (both electric and acoustic) sounds more refined and crunchy with tons of detail and air on it as I hear it more convincing toward natural. The piano keys sounds rounded and pleasant. The BQEYZ Summer somehow deliver decent quality on mid segment as it still retain its smooth and precisely characteristic.


The treble quality of this one is leaning towards bright but somehow I felt some smoothen part (toning down some peaks) somewhere in presence sector on treble region just to avoid the harshness and sibilance. Despite of some soft refining on upper mids/lower treble, it still has that sparkle, clarity and show some good amount of detail retrieval. It still has an airiness and a good extension as I still hear that quality of cymbals strikes as it is convincing to be a natural sounding, snappy as tersive and has that speedy transcient.This will be have a good rating or passable mark by trebleheads and enough to be appreciated by treble-sensitives who still look for a good treble quality in their tracks but still depends on their tolerance.


This is truly one of the strongest points of Summer. It has that expansive wideness and depth of soundstage as if you will feel that you're in big concert hall ( they are even wider than KC2 and Spring 2). The imaging is superb and highly commedable on this one as I can hear it clearly and accurately to determine the directional panning and dynamic signals, pinpointing the placement of instruments and vocals and sensing the spacing and separation on each instrument and the layering is even precise and detailed in each row. This kind of representation on this technicality give me some spacious, 3d-holographic feel vibe.

As I put my verdict here, BQEYZ Summer offers a different tonality flavour compare to its predecessors, This is indeed very impressive on their part despite of almost the same tri-brid set-up from their previous flagships, BQEYZ managed to overhaul on it to sound distinctly and have a contrasting tonal character. If your looking for a set that is fun and musical tuning then this is what you are looking for. A high-end balanced sounding IEM at affordable and decent price.



I am not affliated to BQEYZ nor receive monetary incentives and financial gains as they provide me a review unit for an exchange of factual and sincere feedback from yours truly.

Once again, I would like to thank Elle Zhou for providing this review unit, I truly appreciate on her generosity towards me and other reviewers.

**Note: Changing eartips (from "Atmospheric"(Bassy) stock tips to "Reference"(Vocal tips that was included in Spring 2 but surprising absent on the Summer's included accessories )do some rectification to have some modest improvement on mids **



PLUG TYPE: 3.5mm /2.5mm/4.4mm
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