Short answer: the KZ ZST X. It ranks #849 of 1369 in-ear headphones by sound quality, rated 3.5/5, at $6.99; the BGVP Melody ranks #907, rated 3.4/5, and costs $7.99, so there is not much of a tradeoff to weigh.
The case for the KZ ZST X: A broadly balanced tuning with a preference score of 67 against the Harman target. The tradeoff: An uneven response, 2.5 dB standard deviation from target.
The case for the BGVP Melody: A broadly balanced tuning with a preference score of 66 against the Harman target. Watch for: An uneven response, 2.5 dB standard deviation from target.
Buy the KZ ZST X. It is rated higher for sound quality than the BGVP Melody and costs less, so it is the default pick unless a specific strength of the other one matters more to you.
Still deciding? The full Headphones rankings cover every ranked option.
A broadly balanced tuning with a preference score of 67 against the Harman target.
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A broadly balanced tuning with a preference score of 66 against the Harman target.
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Specifications Side By Side
| KZ ZST X | BGVP Melody | |
|---|---|---|
| Price | 6.99 | 07.99 |
| Ranked | #849 of 1369 in In-Ear Headphones | #907 of 1369 in In-Ear Headphones |
| Form Factor | In-ear | In-ear |
| Back | Closed | Closed |
| Harman Preference Score | 67 (median of 8 squig.link measurements, calibrated to AutoEQ) | 66 (median of 3 squig.link measurements, calibrated to AutoEQ) |
| Deviation From Target | 2.46 dB standard deviation | 2.46 dB standard deviation |
| Tonal Tilt | -0.45 (negative is warmer, positive brighter) | -0.66 (negative is warmer, positive brighter) |
| Sub-bass Extension | Within 6 dB of target down to 20 Hz (+0.4 dB at 30 Hz) | Within 6 dB of target down to 20 Hz (+0.0 dB at 30 Hz) |
| Driver Type | Hybrid | Dynamic |
| Drivers | 1 dynamic driver + 1 balanced armature (10mm dynamic + 30095 balanced armature) | 1 x 12mm Lilin03 carbon crystal PU dynamic driver |
| Impedance | 12 ohms | 18 ohms |
| Sensitivity | 107 dB/mW | 106 dB SPL/mW |
| Frequency Response | 20Hz - 40kHz | 20Hz - 40kHz |
| Weight | 0 lbs (22 g) | - |
| Connection | Wired | Wired |
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 ZST X from achoreviews, aftersound, bukanaudiophile, eplv, hbb, melatonin, pw and vortexreviews; the BGVP Melody from animagus, pw and superreview, all via squig.link.
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