Kiwi Ears - Quartet

In this review, I'll try to compare the Octave with a few different IEMs (Ziigaat x Hangout Audio Odyssey 2 , Oriveti Lowmaster, BQEYZ Frost, Hidizs MK10 Arcsonic, Kiwi Ears Quartet, Tanchjim FOLA, ddHiFi Memory, Oriveti Dynabird, BQEYZ Ni, Hidizs MP143 Salt Gold Titanium Edition) and dongle DACs (Tanchjim, Hidizs, dd Hifi) that I have in my bag. let's get started. I've been testing DACs/Amps a lot lately, and the Octave has managed to become one of my favorites in terms of sound character. A Compact Powerhouse Some DACs impress you with their loudness, brightness, or immediate dramatic effect. The NICEHCK Octave, in my opinion, feels like it was designed by engineers who love long-lasting, comfortable music, not just a test track, but the ability to enjoy full albums to the end. The Octave's greatest strength is how it maintains the musical tapestry as a whole. Bass lines are felt separately from the kick drums. When the mix intensifies, the vocal texture remains stable and balanced. Treble details are heard without turning every cymbal into a spotlight. I appreciate the Octave for its confident sound without being aggressive. And this device has a hidden surprise. Especially from the 4.4mm balanced output, it's really powerful for its size. This extra headroom doesn't just boost the sound. It improves grip, transient stability, and dynamic contrast, especially for planar iem's and stream-loving hybrid headphones. Octave feels more like a small, serious portable front-end than a typical phone accessory. **Technical Specifications and Hardware Overview:** DAC chip: ESS ES9039Q2M Amplification: Dual SGM8262 op-amplifiers Inputs: USB C - Outputs: 3.5mm single-ended and 4.4mm balanced Output power: 150 mW at 32 ohms from 3.5mm, 550 mW at 32 ohms from 4.4mm Supported formats: PCM up to 768 kHz 32-bit, DSD up to DSD256 Dynamic range and SNR: 130 dB, listed as class performance Gain: Low and high gain modes, plus independent hardware volume steps Controls: Dedicated playback controls, app-based EQ support, and firmware updates These numbers matter because they describe the listening experience: This dongle is not only clean, but also has enough voltage and current headroom to keep demanding IEM loads under control, and It doesn't produce a forced sound. **What Does the ES9039Q2M Bring and Why Does It Sound Different Than Normal Cirrus Dongles?** Many portable dongles in this price range rely on Cirrus Logic chips like the CS43198. These generally offer an easy, smooth, slightly rounded presentation, usually a friendly treble, and a softer starting edge. Octave's ES9039Q2M takes a different approach. In a well implemented design, ESS chips generally deliver stronger edge definition, more pronounced separation, and a higher sense of contrast between quiet and loud micro-events. Specifically with the Octave, the ES9039Q2M character isn't used to chase brightness or sharpness. Instead, it's used to improve structure. Transitions start and end more precisely. The image feels more locked in, especially in left to right layouts. Low frequency texture becomes easier to read. You hear not just the bass weight, but also the bass articulation. I quite like that. The main point isn't that the ESS is always better than the Cirrus. It can be explained by the Octave placing more emphasis on control, structure, and dynamic stability, while most CS43198 dongles prioritize flow, smoothness, and comfort. The Octave is still quite listenable, but its way of holding music together feels more like a miniature desktop chain. This difference becomes very apparent when switching between the ES9039Q2M on the Octave and the CS43198 dongle on a heavy metal track or a planar IEM with sharp transition behavior. The Octave keeps the image cleaner and more stable. You get less blur, more space, and a stronger sense that the device isn't reaching its limits. **Overall Sound Characteristics:** Generally, the Octave sits in a neutral to slightly warm region, but with a distinctly controlled backbone. It's not a thick, syrupy dongle. Nor is it treble focused. The bass is tight and well damped, the mid frequencies are clean and realistically weighted, and the treble is extended but rarely sharp. The soundstage isn't artificially large, but it's cleanly layered with noticeably strong imaging. If I had to describe the emotional feel, I'd say it's the sound of a device that relaxes you because it maintains its calmness. You think less about the equipment and spend more time following the setup. **Buttons, Usability, and Daily Life:** The Octave is one of those dongles that feels like it was designed by someone who uses dongles outside the home. The hardware volume control (100-step) is important. The gain shift knob is important. The playback controls are important. App EQ support is important when you want small, subtle adjustments instead of changing equipment. In practice, the dedicated controls make the Octave feel more like a real component than a fragile accessory. You can keep your phone's volume stable, manage the gain correctly, and keep noise low with sensitive IEMs. Software updates and sound memory behavior also help reduce daily friction. **Comparisons with Other DAC Amplifiers:** **Octave (ES9039Q2M) vs Tanchjim Luna (dual CS43198)** The Tanchjim Luna is a device that captivates people with its smoothness and fluidity. It's built around dual CS43198 DAC chips, and this Cirrus foundation tends to create a smoother treble energy and a more rounded crossover shape. When you switch from the Luna to the Octave, the first thing you'll notice isn't the volume, but the structure. The Octave draws cleaner lines around instruments. The Luna, on the other hand, blends them a bit more, which can give a fuller and more forgiving feel. The bass on the Luna tends to be a bit softer on the attack, and comes with a nice bloom that makes vocals and guitars feel warmer. The Octave tightens this behavior. It doesn't reduce weight, but it reduces glare and increases grip. In kick heavy heavy metal tracks, Octave makes it easy to follow double kick patterns. In Luna, the same pattern feels more rounded and musical, but not as sharply defined. Mid frequencies are a matter of personal preference. Luna can make vocals feel more intimate and emotionally rich, especially in vocal centric music and slower rock. Octave keeps vocals honest and stable with excellent clarity and separation when the mix gets crowded. With Luna, you might feel the singer is closer. With Octave, you feel the band is better organized. The treble also creates a distinct contrast. If you are sensitive to treble, Luna is easier to listen to. Octave is still controlled, but it reveals more upper frequency information and does so with a stronger contrast. In well recorded material, Octave feels more complete. In warm recordings, Luna might be a safer choice. If you want a dongle that feels like a warm lamp in your room, Luna is nice. If you want a dongle that feels like a clean studio window without being sharp, Octave is the right choice. **Octave (ES9039Q2M) vs ddHiFi Eye3 (dual CS43198)** The Eye3 is built on ddHiFi’s concept of portable power and compact elegance. Many Eye3 variants in the family utilize the dual CS43198 design, and the overall sound identity tends to be powerful, vibrant, and instantly engaging. Compared to the Octave, the Eye3 generally feels more eager in its presentation. The leading edges of the bass hits are more noticeable. The sound may feel more lively on first impression. The Octave responds with calmness and scaling. When you listen for longer periods, the Octave tends to feel more balanced across the spectrum. The Eye3 can emphasize excitement, which is great for energetic pop, EDM, or rock music where you want a little more adrenaline. The Octave feels more linear. It keeps the mid-frequencies centered and avoids forcing treble energy just to appear detailed. In complex music, especially intense metal mixes, the Octave has the advantage in organization. The Eye3 can deliver bigger and more instantaneous sound, but the Octave keeps the layers more separate. If you value the clarity of guitar harmonies, the separation of the bass guitar from the kick drum, and the stability of vocal placement when the chorus explodes, the Octave is generally more reliable. The treble on the Eye3 can feel more lively depending on the headphones. The Octave, despite being an ESS implementation, remains more controlled with a slightly softer top energy. This may not seem intuitive, but the Octave's tuning prioritizes consistency over showmanship. In short, the Eye3 is a great choice for those who want energy and punchy sound with minimal effort. The Octave, on the other hand, is for those who want a dongle that acts as a stable reference point in a wider collection. **Octave vs. Hidizs S9 Pro Plus (ES9038Q2M) Comparison** This is the most interesting comparison because both devices are in the ESS world and present music differently. The S9 Pro Plus uses the ES9038Q2M. It's known for its clarity, distinct details, and very clean, precise presentation. The Octave, on the other hand, uses the ES9039Q2M and, on paper, offers noticeably higher balanced power. When switching between the two, the S9 Pro Plus generally has a sharper focus. It highlights micro-details, making the edges of cymbals and the texture of strings more prominent. The Octave feels a little more natural in the way it integrates this detail. It doesn't hide the information, but it doesn't force it into the spotlight either. The result is a presentation that feels more musical and less like a review lamp. Bass control is strong on both, but the Octave's higher headroom gives a more secure hit feel, especially with stream-loving IEMs on 4.4mm. The S9 Pro Plus can deliver an extremely clean sound, but the Octave feels more effortless when the track dynamically gets heavier. I hear a greater philosophical separation in the mid-frequencies. The S9 Pro Plus can deliver very clear and precise sound, sometimes veering to a cooler tone depending on the headset. The Octave keeps the mid-frequencies stable and slightly more tolerant; this can be a boon for in-ear monitors that are aggressive in the upper mid-frequencies. The treble is more pronounced in the S9 Pro Plus. The Octave has a softer and more natural damping. If you live for maximum clarity and sharp separation, the S9 Pro Plus will excite you. If you want high resolution with less fatigue and a larger power field, the Octave becomes a more flexible everyday use option. **Octave (ES9039Q2M) vs ddHiFi Mountain 3 (pair CS43198)** The Mountain 3 is a small device that often surprises people with its musical weight. Many Mountain 3 designs are based on the dual CS43198, and the typical result is a warmer, fuller tone with easy highs. The Octave, again, takes on the role of structure and grip. The Mountain 3's bass can feel a bit thicker and more relaxed. It provides intensity, especially in the mid-bass. The Octave tightens this area and increases the sense of speed. In fast rock and metal, the Octave is generally a cleaner and more distinct choice. In vocal jazz and slower acoustic music, the Mountain 3 sounds more intimate and romantic to your ears. The Mountain 3's mid-frequencies feel fuller and a bit smoother. The Octave feels cleaner and more detached. The balance here is between emotional warmth and analytical organization. Neither is wrong, but they serve different moods. The Mountain 3 invites you to sit back. The Octave invites you to follow the arrangement. The Mountain 3's highs are generally safer, with less emphasis on the upper end. The Octave covers a wider area and shows more air. If you're sensitive to high frequencies, the Mountain 3 might feel softer. If you want more space and clarity, the Octave is a more complete window. Power is another practical difference. The Octave's balanced output headroom is in a different league on paper, and listening generally translates to better control and dynamics. The Mountain 3 might be magical for IEMs. The Octave, on the other hand, feels magical and can deliver even more powerful performance when needed. **NICEHCK Octave vs IEM Pairings:** **Octave × Ziigaat x Hangout Audio Odyssey 2:** The Ziigaat Odyssey 2 has a sound character I quite like, naturally offering a wide and somewhat cheerful tone. With the Octave, that cheerfulness has become more disciplined. I first notice the change in the bass. The Odyssey 2 can sometimes be a little loose or exuberant depending on the source, but the Octave tightens the low frequencies and provides a cleaner start and finish. Kick drums become more prominent, and bass guitar lines gain a clearer pitch instead of becoming a single low frequency blot. The mid frequencies benefit from the Octave's separation. The Odyssey 2 has a sense of airiness that can sometimes make the vocal placement feel a little relaxed. The Octave brings the vocal image to a more stable center position by cleaning up the surrounding space, rather than aggressively pushing it forward. This makes the guitars more textured and the layering more pronounced, especially in intense rock tracks. The treble remains open and lively, but the Octave reduces the glare. You still get that airy soundstage, but the cymbals feel more controlled and less bouncy. The biggest gain is how the Octave improves the layering of depth. The Odyssey 2 remains wide, but now feels more three dimensional. Instruments are positioned from front to back, not just left and right. This pairing feels like taking an already enjoyable IEM and giving it a more mature backbone. It remains fun, but becomes more reliable, more coherent, and more trustworthy in a full playlist. **Octave × Oriveti Lowmaster:** The Lowmaster is another IEM I like, entirely designed for impact and rhythm, but when driven correctly, it feels less like just a loose bass toy. The Octave is a surprisingly good pairing as it provides control without sacrificing weight. The bass hits hard, but the damping remains clean. The sub bass feels deep and confident, but the mid bass doesn't spill over into vocals. This is important because the Lowmaster can sound thicker on warmer sources. Octave keeps it energetic, but not clogged. The mid frequencies become clearer and more readable. Vocals gain better articulation, and guitars have more impact without becoming sharper. In metal and hard rock, this helps the mix breathe. You can follow double hit passages more easily because the low frequencies remain consistent. Lowmaster retains its identity, but delivers a more serious sound. The treble is safe and not tiring. If Lowmaster is tuned to avoid harshness, Octave respects that tuning while extracting enough detail to preserve the texture of the cymbals. You don't suddenly get a bright iem, you get a cleaner one. The soundstage isn't huge, but Octave improves separation and imaging precision within that space. The result is a punchy and controlled feel, like a cramped club space rather than a large concert hall. If you love Lowmaster for its physical structure but want a more structured sound, Octave is a resource that quietly corrects that. **Octave × BQEYZ Frost:** The Frost has an airy, expansive character and a treble presentation that can be energetic depending on the chain. The Octave makes the Frost feel more balanced. The bass becomes a bit more solid and distinct, which is valuable because The Frost sometimes prioritizes clarity over weight. With the Octave, the low frequencies feel more solid. It's not bass heavy, but it sounds more complete. I feel fast and clear beats. The Frost's mid frequencies can feel a bit weak if the source is overly clinical. The Octave adds a bit of fullness and keeps the vocals stable. This makes vocal centric tracks feel more intimate without crashing the stage. Guitar textures also become more believable, especially in the lower mid frequencies where the Frost can sometimes feel a bit light. The treble is where the Octave feels more secure in matching. The Frost still retains its airiness and sparkle (thanks to its great micro planar driver), but the energy in the upper frequencies feels less sharp. Cymbals remain clear, but damping feels softer. You hear sparkle and roomy hints without the feeling that the upper frequencies are being forced for dramatic effect. The soundstage remains wide and open, offering powerful imaging. The Octave helps the Frost maintain its breadth and improve separation. In a dense mix, Frost sounds cleaner and less chaotic with the Octave. The overall effect is a more mature Frost; still airy and detailed, but less likely to tire you out during a long listening session. **Octave × Hidizs MK10 Arcsonic:** The MK10 Arcsonic is a fast and resolving IEM that can quickly reveal the personality of the source. I didn't think I would like this IEM this much. It performs great for its price. Combined with the Octave, the MK10 finds its right companion. The bass remains tight and fast, but gains a density that makes the MK10 feel less thin. You get impact without losing speed, which is exactly what you want in technical in-ear monitors. Mid-frequency clarity remains excellent. Vocals are clean and instantly audible, but Octave prevents them from becoming sharp. This is important because the MK10 can feel aggressive when paired with a bright source. Octave keeps the upper mid-frequencies under control while preserving articulation. Guitars sound clear, and complex arrangements remain layered rather than collapsing. The treble feels extended and detailed. Octave doesn't turn the MK10 into a dull listening experience, but it eliminates that glassy sharpness that can appear in some ESS applications. The result is energetic but not piercing. Cymbals have texture, not just brightness. The soundstage and imaging are strong. The MK10 already offers good imaging, and Octave provides a stable foundation. You get better separation and a more stable center image. This pairing is ideal for listeners who want technical performance but prefer to enjoy the music rather than analyze it. It feels sharp and capable, but surprisingly comfortable for extended listening sessions as well. **Octave × Kiwi Ears Quartet:** The Quartet is one of those in-ear headphones whose sound can vary depending on the source. With the Octave, it became more consistent and emotionally satisfying. When paired with the Octave, the bass gained a more prominent and slightly stronger beat. The Quartet didn't suddenly transform into a sub bass beast, but the low frequencies feel better shaped, which helps the rhythm sections sound more confident. The mid frequencies became more defined. Vocals sound fuller and more stable, with a clean sense of placement. The Quartet can sometimes feel a little unbalanced when the chain is too hot or too bright. The Octave neither dulls nor screams the mid frequencies, it's right in that sweet spot. It gives vocals believable body and preserves the texture of the guitars. The treble remains smooth and controlled. The Quartet has enough energy to sound open, and the Octave maintains that openness while keeping the edges clean. Cymbals and strings retain their sparkle, but you don't feel any harshness. The soundstage isn't exaggerated, but the imaging is orderly. Octave helps organize the Quartet's sound, which is important when the mix gets denser. This pairing feels like a well balanced everyday setup that doesn't require much attention. Genre changes, long playlists, and different listening moods work seamlessly. **Octave × Tanchjim FOLA:** FOLA can be a lively and detail-oriented IEM that sometimes benefits from a limited source. Octave delivers exactly that. The bass remains fast and controlled, and Octave prevents the bass from sounding too weak. You still get a clean effect, but there's a bit more weight, which makes the drums feel more physical. The mid-frequencies become smoother and more natural. While FOLA tends to be bright in the upper mid-frequencies on some sources, Octave gently calms this area without flattening details. Vocals remain clear, but are less prone to sharpness. Guitar harmonics and string overtones feel more integrated rather than standing out as separate bright elements. The treble remains extended and clear, while Octave prevents it from becoming tiring. You still hear the micro details, room cues, and the final tones of the cymbals, but the overall presentation offers a more relaxed experience. It's the kind of match where you find yourself not wanting to turn the volume down when you finish an album. The soundstage is clean and offers good separation. FOLA is capable of delivering very high quality sound, and Octave supports this, while also making it more musical. If you love FOLA for its clarity but want a more forgiving chain for longer sessions, Octave is a very smart choice. **Octave × ddHiFi Memory:** Memory has a warm and inviting tone that sometimes risks sounding a little too soft on very soft sources. Octave gives it structure. This headset works quite efficiently with its planar driver. The bass has become tighter and more readable, and the mid bass region has gained better control. This means you still get warmth, but with less muddiness. I like the bass texture in their planar drivers. The mid frequencies retain the emotional quality that makes Memory special. Vocals remain intimate and textured, but Octave has increased the clarity around them. You hear more separation between vocal layers and background instruments. Acoustic guitars gain clearer string definition. Piano notes become more distinct and dampen more steadily. I'd say these two get along quite well. The treble remains smooth, but Octave seems to open up the upper end a bit. You get more air without sharpening Memory. This helps to broaden the soundstage perception and makes the sound feel less closed off. The overall effect is that Memory retains its relaxed identity but gains resolution and organization. This pairing is perfect for vocal jazz, acoustic sessions, and any kind of music where you primarily want tone and emotion. Octave didn't turn Memory into an analytical monitor, but it feels like it cleaned up the Window, making the warmth feel intentional, not blurry. **Octave × Oriveti Dynabird:** The Dynabird is a fairly balanced dynamic driver IEM. It's all about speed, punch, and rhythmic accuracy, especially for instrumental work and metal. Octave fits this purpose perfectly. With this pairing, the bass is fast and tight. You get impact without blasting. Kick drums are sharp, and bass guitar lines remain distinct even under heavy distortion. The mid-frequencies are energetic but controlled. Dynabird's strength is keeping guitars clear without thinning them out. Octave reinforces this balance by keeping the lower mid frequencies stable and the upper mid frequencies clean. Vocals stand out in dense mixes, but don't scream. This is important for metal, where the mix can quickly become dense. The treble is clear and informative, but the Octave prevents it from becoming sharper. The cymbals have sharpness and texture, and the atmosphere around the instruments feels realistic. You get plenty of detail for instrumental music, but the listening experience remains comfortable. The soundstage is medium sized but very even. The imaging is clear, and the separation remains strong even when the track intensifies. The Octave and Dynabird pairing feels like a focused instrument for fast music. It offers drive and clarity without sacrificing tonal stability, which is exactly what instrumental and metal listeners want. **Octave × BQEYZ Ni:** This is a new IEM sent to me for review, and I can say I quite like it. The Ni tends to reward a source that can maintain consistency without softening its character. The Octave does this well. The bass becomes more disciplined, providing a cleaner transition to the mid-frequencies. You get a solid low frequency foundation, but you never feel like it's pushing the rest of the spectrum back. The mid frequencies have very good body and clarity. The vocals are natural and centered, while the instruments have a realistic tone. Octave's separation helps Ni handle complex passages without collapsing. This is especially noticeable in layered rock and orchestral pieces where multiple mid frequency elements compete. The treble is extended and clean. Octave's ESS based structure makes it easy to track micro details without forcing brightness. Ni maintains its open feel while keeping the upper frequencies under control. Cymbals and strings produce a textured sound, not a sharp one. The soundstage appears orderly with good left and right placement and a respectable depth. This pairing is one of those setups that makes you stop thinking about tuning and start thinking about the music. While Ni maintains its personality, Octave provides the stability and hold that allows that personality to emerge in a more refined way. **Octave × Hidizs MP143 Salt Gold Titanium Edition:** The MP143 is a planar iem that loves to work with a source that has headroom and control. The Octave delivers both. The first thing you'll notice is how well the bass behaves. Planar bass can feel fast, but depending on the chain, it can sometimes feel a little light. With the Octave, the MP143 gains body without losing speed. The bass is tight, punchy, and clean, and remains balanced even in fast passages. The mid frequencies remain transparent, which is one of the MP143's greatest strengths. The Octave keeps the mid frequencies stable, allowing you to hear subtle layering in guitars, synth pads, and vocal harmonies. There's a sense of effortlessness that emerges when the track intensifies. Instead of turning into a wall of sound, it remains layered and readable. The treble is airy and detailed. The MP143 can sometimes sound a little dense in the upper region with a sharper source. The Octave keeps this region under control while still providing air and extension. The cymbals and upper harmonics are prominent, not pushed through. The soundstage is wide enough, but the real gain is in imaging and separation. This duo feels like a portable system that could really replace larger systems for certain listening sessions. If you're using the MP143 for instrumental or technical genres, the Octave makes it feel faster, cleaner, and more secure. **Pros** Very high output power from a 4.4mm balanced output for a dongle-class device Clean, controlled ESS-style resolution without harshness Excellent layering and rendering for complex music Useful physical controls and gain options for everyday use App EQ and software support extend lifespan Wits well with both warm and technical IEMs **Cons** If you want a soft, romantic, very warm Cirrus-style presentation, the Octave may feel too structured The soundstage focuses on organization rather than artificial breadth Best performance comes from the 4.4mm balanced output, so the right cable is important **Conclusion** The NICEHCK Octave is the kind of device that consistently deserves its place. It's powerful, but uses that power for control rather than brute force. It's detailed, but the kind that refuses to be sharp. With its actual knobs and gain control, it's practical and feels designed for everyday listening rather than occasional testing. Most importantly, it's scalable across a collection. Whether you're playing a fast planar, a warm musical hybrid, or a clean reference tuned set, Octave does the same thing every time: it refines the music, tightens the bass, balances the mid-frequencies, and keeps the treble clear without turning it into a spotlight. If you want a single dongle that can sit in the middle of your rotation and make almost everything sound more balanced, Octave is a serious contender. \* [NICEHCK Octave Official Link](https://www.nicehck.com/products/nicehck-octave-es9039q2m-flagship-portable-dac?srsltid=AfmBOoqNklilBaYBfI-nLoqrQJyJUXayuqSMBOIKbaTQWwVwlpuvfKlS) **Disclaimer:** I would like to thank **TempoTec** for providing the **V1** for review purposes. I am not affiliated with **TempoTec** beyond this review and these words reflect my true and unaltered opinions about the product. **\* All Photographed taken by me (Ahmet Derici) from** [**Instagram:** **u/electroaudioworld**](https://www.instagram.com/electroaudioworld/) **\*** **Used photo Gear : Sony A7 III + Sigma 24–70mm F/2.8 DG DN II Art Lens** \*

Kiwi Ears Quattro or CKS1100 if you want bassier, CKR100 if you want all around

Quartets are a great pair of IEMs, I had a chance to sample them. Warm sound, great mid and sub bass coverage sparkly highs with pretty nice detail. They are fun

Id recommend Kiwi ears Quarter. Great allrounder.

The Quartet was my second IEM and I really liked it.

That might work. It has two dynamic drivers in isobaric configuration for better bass. You might also check out the newer Kiwi Ears Airoso. It also has great bass but would have better highs. It has an MSRP of $129 but goes on sale for under $100.

Looks like a good roundup. I have both the Kiwi Ears Quartet and Airoso among others. The Airoso is my current favorite, but I don’t listen to the same kind of music you do so I can’t speak to its suitably for that type of music.

I was going to suggest heading over to the IEMS subreddit but all you get there are wildly differing opinions on the same £20 IEMs. I bought sets of Kiwi Quartets and Cadenzas over the last 6 months. Total disappointment, especially the feeble Cadenzas. The Apple Earpods (not the ear buds) are actually quite decent. I'd stick with those for now.

Ok, I'll go with my experience, I started with the Kiwi quartet (nice basses), then the Simgot EM6L, then I took the Ziigaat Odyssay and I'll tell you, my best choice falls on the Simgot, the crazy Odyssay, absolute definition of massive sub bass, incredible soundstage width and tonal clarity but what an effort... the Simgot tweaked just on the bass (I use Qudelix 5k DAC) becomes syraordinaria, always enjoyable and precise... in my experience I recommend Simgot, kiwi quartet for bassy electronics, Odyssay for instrumental pieces perhaps without too high-pitched wind instruments or female voices (they break the ears) and not too high volume.

If you are looking for some iems with some more bass on them, the kiwi ears quartets definitely do. Although like other people on here, I would recommend trying to adjust to the zero blue's for awhile before pulling the trigger on a new iem.

Do you use EQ? EQ'd bass on Fiio K5 Pro ESS with my Quartets is awesome.

I am enjoying my kiwi ears quartet. ,£80 direct from China. The added tariffs may well put these out of your price range.

For my ears I found it surprisingly smooth for a technical set, but it does walk a fine line of being sharp on some tracks, it really depends on your treble sensitivity. If you don't want to risk it, Kiwi Ears Quartet is a much safer bet.