Short answer: the KZ Xtra. It ranks #501 of 1291 in-ear headphones by sound quality, rated 3.9/5, at $68; the KZ ZAX ranks #562, rated 3.8/5, at $65.99. With prices this close, go by the sound-quality ranking rather than the cost.
Why pick the KZ Xtra: A broadly balanced tuning with a preference score of 73 against the Harman target. Watch for: An uneven response, 2.0 dB standard deviation from target.
Why pick the KZ ZAX: Across hobbyist measurements on squig.link sub-bass sits within 0.2 dB of target down to 20 Hz, and a 3.2 dB bass lift adds warmth and punch for pop and electronic music. The tradeoff: A 9 dB peak near 11.2 kHz lifts the top octave about 6 dB above target, which can make cymbals and sibilants sound sizzly on bright recordings, and a 3.8 dB dip near 3.4 kHz slightly recesses vocals.
Buy the KZ Xtra. It is rated higher for sound quality, and the $2.01 saving on the KZ ZAX is not enough to make up the difference.
Still deciding? The full Headphones rankings cover every ranked option.
A broadly balanced tuning with a preference score of 73 against the Harman target.
Amazon $68.00 eBay
Across hobbyist measurements on squig.link sub-bass sits within 0.2 dB of target down to 20 Hz, and a 3.2 dB bass lift adds warmth and punch for pop and electronic music.
Amazon $65.99 eBayPrices on this page were last checked October 16, 2026 at 5:46 PM UTC. Product prices and availability are accurate as of that date/time and are subject to change; the price and availability shown on Amazon at the time of purchase will apply to the purchase of this product.
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Specifications Side By Side
| KZ Xtra | KZ ZAX | |
|---|---|---|
| Price | $68.00 | $65.99 |
| Ranked | #501 of 1291 in In-Ear Headphones | #562 of 1291 in In-Ear Headphones |
| Form Factor | In-ear | In-ear |
| Back | Closed | Closed |
| Harman Preference Score | 73 (median of 4 squig.link measurements, calibrated to AutoEQ) | 71 (measured by crinacle, via AutoEQ) |
| Deviation From Target | 1.99 dB standard deviation | 2.29 dB standard deviation |
| Tonal Tilt | -0.48 (negative is warmer, positive brighter) | -0.43 (negative is warmer, positive brighter) |
| Sub-bass Extension | Within 6 dB of target down to 20 Hz (-0.7 dB at 30 Hz) | Within 6 dB of target down to 20 Hz (-0.7 dB at 30 Hz) |
| Connection | Wireless | Wired |
| Driver Type | Dynamic | Hybrid (1 dynamic + 7 balanced armature) |
| Drivers | 1 x 10mm dynamic driver | 1 x dynamic + 7 x balanced armature |
| Frequency Response | 20Hz - 20kHz | 10Hz - 40kHz (Manufacturer specified) |
| Bluetooth Version | 5.4 | - |
| Bluetooth Codecs | aptX Adaptive, aptX, AAC, SBC | - |
| Active Noise Cancelling | Yes (~55dB hybrid ANC) | - |
| Battery Life | 8 hours (earbuds), 32 hours (with charging case) | - |
| Impedance | - | 24 ohms |
| Sensitivity | - | 113 dB |
Frequency Response Compared
Both headphones’ measurements overlaid on the Harman target. Above the target sounds louder in that range, below it quieter. Each curve is the median of several independent measurements, shifted so its 500 Hz to 2 kHz average sits at 0 dB, so only the tuning is compared.
Measurement data: the KZ Xtra from dhrme, gadgetrytech, hbb and regancipher; the KZ ZAX from achoreviews, melatonin, pw and vortexreviews, all via squig.link.
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