Short answer: a tie on sound quality. Both are rated 4.3/5 (#203 and #220 of 1291 in-ear headphones) at nearly the same price ($20 vs $20.99), so choose on features and fit.
Why pick the TANCHJIM ZERO DSP: A broadly balanced tuning with a preference score of 78 against the Harman target. The catch: Treble about 2 dB above target from 3 to 10 kHz, which can sound sharp or tiring at higher volume.
What the TRN Dolphin does well: The median of 8 hobbyist measurements gives it a very good Harman preference score of 77 with a 1.72 dB spread, and its mids sit within about 0.9 dB of target, so vocals and instruments sound natural. The tradeoff: A 10.4 dB peak near 11.5 kHz can make cymbals and sibilance sound sharp.
Buy the TANCHJIM ZERO DSP or the TRN Dolphin on features: they are rated the same for sound quality at close to the same price.
Looking for alternatives? See the complete Headphones rankings.
A broadly balanced tuning with a preference score of 78 against the Harman target.
e-earphone (JP) eBay
The median of 8 hobbyist measurements gives it a very good Harman preference score of 77 with a 1.72 dB spread, and its mids sit within about 0.9 dB of target, so vocals and instruments sound natural.
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Specifications Side By Side
| TANCHJIM ZERO DSP | TRN Dolphin | |
|---|---|---|
| Price | $20 | $20.99 |
| Ranked | #203 of 1291 in In-Ear Headphones | #220 of 1291 in In-Ear Headphones |
| Form Factor | In-ear | In-ear |
| Back | Closed | Closed |
| Harman Preference Score | 78 (median of 3 squig.link measurements, calibrated to AutoEQ) | 77 (median of 8 squig.link measurements, calibrated to AutoEQ) |
| Deviation From Target | 1.49 dB standard deviation | 1.72 dB standard deviation |
| Tonal Tilt | +0.09 (negative is warmer, positive brighter) | +0.14 (negative is warmer, positive brighter) |
| Sub-bass Extension | Within 6 dB of target down to 20 Hz (+0.6 dB at 30 Hz) | Within 6 dB of target down to 20 Hz (+0.4 dB at 30 Hz) |
| Connection | USB-C | Wired |
| Driver Type | Dynamic | Dynamic |
| Drivers | 1 x 10mm dynamic | 1 x 10mm dynamic |
| Impedance | 32 ohms | 32 ohms |
| Sensitivity | 118 dB/Vrms | 106 dB |
| Frequency Response | - | 20Hz - 20kHz (Manufacturer specified) |
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 TANCHJIM ZERO DSP from hobbytalk, tanchjim and therollo9; the TRN Dolphin from aftersound, audioamigo, eplv, jaytiss, kuping-sensi, practiphile, soundcheck39 and tonedeafmonk, all via squig.link.
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