Short answer: the BASN Bmaster5. Both are rated 3.7/5 for sound quality (#665 and #679 of 1291 in-ear headphones), and the BASN Bmaster5 costs $159.99 against $169 for the ROSESELSA CJ20, and with sound quality even, the cheaper one is the better buy.
Why pick the BASN Bmaster5: A hybrid with a DLC dynamic driver and four balanced armatures. The catch: Its score rests on three measurements.
What the ROSESELSA CJ20 does well: A broadly balanced tuning with a preference score of 70 against the Harman target. Watch for: An uneven response, 2.2 dB standard deviation from target.
Buy the BASN Bmaster5. Both are rated the same for sound quality, and it costs $9.01 less than the ROSESELSA CJ20.
Looking for alternatives? See the complete Headphones rankings.
A hybrid with a DLC dynamic driver and four balanced armatures.
Amazon $159.99 eBay
A broadly balanced tuning with a preference score of 70 against the Harman target.
HiFiGo $169 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
| BASN Bmaster5 | ROSESELSA CJ20 | |
|---|---|---|
| Price | $159.99 | $169 |
| Ranked | #665 of 1291 in In-Ear Headphones | #679 of 1291 in In-Ear Headphones |
| Form Factor | In-ear | In-ear |
| Back | Closed | Closed |
| Connection | Wired | Wired (3.5mm) |
| Driver Type | Hybrid | Dynamic |
| Drivers | 1 x 10mm dynamic + 4 x balanced armature | 1 Dynamic (10mm topological) |
| Harman Preference Score | 70 (median of 3 squig.link measurements, calibrated to AutoEQ) | 70 (median of 3 squig.link measurements, calibrated to AutoEQ) |
| Deviation From Target | 2.24 dB standard deviation | 2.15 dB standard deviation |
| Tonal Tilt | -0.42 (negative is warmer, positive brighter) | -0.47 (negative is warmer, positive brighter) |
| Sub-bass Extension | Within 6 dB of target down to 20 Hz (-1.7 dB at 30 Hz) | Within 6 dB of target down to 20 Hz (+2.3 dB at 30 Hz) |
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 BASN Bmaster5 from audioamigo, bakkwatan and ducbloke; the ROSESELSA CJ20 from aftersound, atechreviews, audioamigo, hbb, jaytiss and lestat, all via squig.link.
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