When the upgrade is a downgrade…
The KB02 and KB03 are both resin-shell dynamic driver headphones that include a vibration driver, or bone conduction unit, operating in the lower frequencies.
MAIN TAKEAWAY KB02
- Excellent value
- Quite neutral
- Smooth yet detailed
MAIN TAKEAWAY KB03
- Major tuning fault around 200 Hz
- Bass light
- Clean treble
- Get the KB02 instead
The KB02 features a 10 mm dynamic driver with a beryllium-coated diaphragm, along with a 10 mm elastomer vibration driver/bone conduction driver. It is priced at around 30 USD.
The KB03 features a similar 10 mm main dynamic driver with a beryllium-coated diaphragm, but adds a high-frequency Knowles balanced armature driver. It also includes a 10 mm vibration driver/bone conduction driver, similar to the KB02 but “updated” . It is available with a cable-mounted microphone and is priced at 50 USD.
The KB02 and KB03 are both available side by side as complementary offerings from KBEAR.
KBEAR KB02 SPECIFICATIONS
- Drivers 2 total: 1 x 10mm full range DD with beryllium-plated diaphragm and 1 x 10mm elastomer bone conduction driver
- Impedance: 40 ohms
- Sensitivity: 108 dB/mW
- Cable: 1.2m OFC copper 4-core 6N
- Resin shell
- Cable connectors: 0.78 mm 2-pin
- Cable termination: 3.5 mm jack
- Tips: 3 types in 3 sizes
- Non detachable metal nozzles
- Color: Purple, Misty Blue, Maple Brown
Current price and availability:
- Amazon: KBEAR KB02
- AliExpress: KBEAR KB02
- KeepHifi: KBEAR KB02
KBEAR KB03 SPECIFICATIONS
- Driver: 3 total – 1 x 10mm full range DD with beryllium-plated diaphragm 1 x Knowles FK high frequency BA driver 1 x 10mm elastomer updated bone conduction driver
- Impedance: 9.4 ohms
- Sensitivity: 101 dB/mW
- Cable: 1.25 m OFC copper 4-core 5N
- Resin shell
- Cable connectors: 0.78 mm 2-pin
- Cable termination: 3.5 mm jack
- Tips: 3 types in 3 sizes
- Mic: with or without mic
- Resin nozzles
- Colour: purple or green
Current price and availability:
- Amazon: KBEAR KB03
- AliExpress: KBEAR KB03
- KeepHifi: KBEAR KB03
BUILD AND DESIGN
The KB02 and KB03 are very similar in build. Both feature resin shells. The KB02 has a large non-detachable metal nozzle, while the KB03 has a smaller resin nozzle. Both use thin, simple black cables and are available in several colors. The KB03 is also available with a microphone cable. Both are medium to large in size, but I find them comfortable to wear.
VIBRATION DRIVER
A major selling point is the vibration driver, also known as a bone conduction unit. These drivers are usually used for higher frequencies in IEMs, but in this case it is tuned for lower frequencies to increase bass tactility.
However, vibrations travel poorly through standard silicone ear tips. Molded custom-made tips would likely provide a very different experience, as they create a larger and former contact surface with the ear canal and conduct vibrations more effectively than standard silicone tips. Certain types of firmer silicone or foam tips may also work.
That said, I tried my Comply foam tips and did not experience much difference compared to the SpinFit CP145 silicone tips used in this review.
FREQUENCY RESPONSE CURVE
In the picture above, you can see the frequency response curves provided by the manufacturer. What stands out immediately is the unusual dip and peak around 200 Hz on the KB03. When I first saw it, I hoped it was a measurement issue related to the vibration driver. However, as my listening impressions will show, this dip and peak are clearly audible and significantly affect most music payback in a negative way.
Luckily, the KB02 does not have these issues. It appears that the KB03 has a poorly implemented vibration driver, which is very disappointing.
TRACK-BY-TRACK COMPARISONS
Associated equipment:
- Amplifier: Topping A90
- DAC: RME ADI-2 DAC FS
- Tips: SpinFit CP145 on both
How Deep by John Scofield
The KB03 is very airy. The double bass is quite polite but still feels tactile, the electric guitar a bit crisp, and the percussion is very snappy.
The KB02 is better. It is more balanced, with more bass and a warmer, smoother feel. It is simply more natural and still technically impressive.
Impedans by Erlend Apneseth
The KB03 delivers a very airy and dynamic sound; it is crisp and tactile, though the bass is not very prominent.
The KB02 is warmer and smoother, with greater bass presence, yet retains the same tactility and dynamic character as the KB03.
Outlaws by Bill Frisell
The KB03 is again airy and crisp. The double bass is polite and there is a tactile feel to the music, but it is a bit dry and the tonality is a bit off.
The KB02 essentially has the positive sides of the KB03, but it is warmer, smoother, and more natural. The bass is more prominent, but not overpowering, just nicely balanced.
Eye of the Day by Marta del Grandi
The KB03 presents a main snare drum that has a very strange, unusually strong presence, probably the strong peak and drop in the frequency response you can see in measurements around 200 Hz. I think it has something to do with the vibration driver. The vocals are however very delicate and smooth.
The KB02 is much better here. The snare is not strange or unusual, and the vocals are similarly delicate. The delivery is both smooth and snappy.
The Hidden Camera by Photek
The KB03’s bass is polite but very even in response, with a tactile quality to it. The percussion is crisp and tight, but things sound a bit dry.
The KB02 has much stronger bass and is also very tactile. The percussion is crisp and tight, but the general tonality is better than with the KB03.
Murmurations by Vega Trails
The KB03 presents a double bass that is tactile but a bit leaner than I am used to. Again the delivery is dynamic and airy, but sounds a bit off.
The KB02 is much more natural in tonality. The bass is a bit stronger, things feel well balanced and airy.
Sandermosen by Maridalen
The KB03 delivers an airy and dynamic presentation. The soundstage is very open and things are very snappy. However, it sounds a bit thin and boxy.
The KB02 on the other hand sounds very natural, warmer and very well balanced. The difference is not enormous, but it is simply tuned better in all the right places (especially around 200 Hz…). The bass is also more powerful as usual, but nicely balanced.
Sujet Tabou by Renaudin and Cahours
The KB03 is very open sounding, with snappy percussion, crisp guitar, and smooth vocals.
The KB02 is however, as usual, a significant step up in terms of tonal balance. It simply sounds more natural, warmer and smoother, yet still retains the technical strong points of the KB03.
Teardrop by Massive Attack
The bass on the KB03 is very polite. The vocals are smooth and very nice. The soundstage is very open.
The KB02 has a more powerful and more natural bass delivery. Everything sounds better balanced, it is very natural, neutral and still open sounding.
Spontaneous Compositorius by Thomas
The KB03 presents a saxophone that is not especially warm but has a nice texture. The percussion is clean and crisp without feeling aggressive. The double bass is polite in presence with good detail.
The KB02 sounds generally more natural with a more pleasing tonal character, but the treble is not as clean as on the KB03.
Come Away With Me by Norah Jones ln
The KB03 has airy vocals and again those strange peaks in the upper bass to lower midrange, which makes it sound unnatural.
The KB02 on the other hand is very nicely balanced. The vocals are still airy but there is more warmth and smoothness, and no funny peaks and dips.
Don’t Stay by Linkin Park
The KB03 sounds mostly fine, but again, there is something going on in the lower midrange that is ruining the rest of the experience. It sounds strange and hollow.
The KB02 is well balanced. The kick drum is punchy but the bass in general is not overpowering. Instrument separation is very good.
WRAPPING IT UP
Sound Signature
The KB02 is nicely balanced and quite neutral.
The KB03 is not too dissimilar, but it has less bass and a nasty peak and dip action in the upper bass to lower midrange that often makes things sound strange. It depends a bit on the track, but it is quite annoying and unnatural.
Treble
This is the only area where I prefer the KB03, probably because of the added high frequency balanced armature driver.
The KB02 has nice, airy treble, bright but not sharp or piercing. The KB03 has similar treble presence, but as mentioned, it’s a tad cleaner in quality.
Midrange
The KB02 has a nicely present, slightly bright but smooth and natural sounding midrange.
The KB03 is similar, but has a that very problematic peak/dip in the upper bass to lower midrange, (around 200 Hz), that really ruins things. It can make the sound very unnatural, boxy and strange.
Bass
The KB02 has what I will call a neutral and natural sounding bass presence. It is certainly not a bass heavy earphone, but neither overly polite. There is a tactile quality to the bass that can likely be attributed to the bone conduction driver.
The KB03 also has a tactile character to the bass, but the quantity is less than the KB02 and it feels generally bass light. The KB03’s peak and dip around 200 Hz is really problematic and often creates a very strange tonality.
Soundstage and Imaging
The KB02 has a wide soundstage and good imaging for the price.
The KB03 is similar.
Detail, Dynamics, and Timbre
The KB02 offers good detail across the frequency range for the price, with nice dynamics and extra tactility. The timbre feels neutral and nothing sounds off or unnatural.
The KB03 has a similar detail level, and because it is more expensive it is not as impressive, even though the treble is more detailed. Dynamics feel less impressive because the bass is so polite. When it comes to timbre it is pretty bad, because of the 200 Hz peak which can make things sound very strange. Most music has elements around 200 Hz, so it is hard to avoid. Maybe a really aggressive EQ profile helps.
CONCLUSION
I was really impressed with the KB02. It has a well balanced, quite neutral and natural sounding signature, both airy and smooth, and the bass presence is spot on for my preferences. I can wholeheartedly recommend it, and at the 35 USD price point it is really impressive.
The KB03, however, is not getting my recommendation. It has a very nasty peak and dip in the upper bass to lower midrange. You can see it in the measurements, and it is certainly not just a measuring oddity. You can hear it on every track that has activity around 200 Hz, which is most music. It sounds boxy and unnatural. In other words, the KB03 is certainly no upgrade in any shape or form – with one exception: the KB03 has cleaner treble, most possibly due to the added Knowles high frequency balanced armature driver.
In total, the KB02 is much better and also cheaper. Honestly, based on my own experience, I cannot see any scenario where the KB03 would be better than the KB02.
KBEAR claims the KB03 has an updated vibration/bone conduction driver. It seems they failed in the implementation. If KBEAR had added the Knowles FK high frequency driver to the KB02 without touching anything else, including the general tuning, we would have had an upgrade, but the KB03 is not that.
In conclusion: The KB02 is great. The KB03 is not.
Thanks for reading. You can support us by purchasing anything using any of our affiliate links.
- Amazon: KBEAR KB02
- AliExpress: KBEAR KB02
- KeepHifi: KBEAR KB02
Any purchase you make on Amazon, Linsoul or AliExpress with any of our affiliate links will give us a small provision at no cost to you.
We only get a provision for items that are not returned, so there’s no incentive for us to recommend something that’s not good.
Linsoul : Headphones, Earbuds, Wireless Earbuds, Desktop DAC/AMP, Portable DAC/AMP, Digital Audio Players,
Amazon: Headphones, IEMs, Headphone Amplifiers, Home Audio or Anything else.
.
If you enjoyed this article or other content on The Headphoneer, you might consider leaving a small donation to keep this website up and running. No donation is too small. Thanks for supporting us!
If you like our work please follow us on Instagram, Facebook and Twitter , it will help us grow. Sharing is caring 🙂
