Short answer: the ISN Audio Neo 3. It ranks #1054 of 1369 in-ear headphones by sound quality, rated 3.1/5, at $99; the Etymotic ER4XR ranks #1060, rated 3.0/5, and costs $299, so there is little reason to consider the other one.
What the ISN Audio Neo 3 does well: A published AutoEQ preset corrects its response toward the Harman target, so a few minutes of EQ setup closes most of the gap. The catch: Treble about 2 dB below target from 3 to 10 kHz, which can sound dull or veiled next to brighter headphones.
Why pick the Etymotic ER4XR: Upper mids sit within 0.5 dB of the Harman target and low mids within 0.4 dB, so vocals and instruments come through clearly and naturally. The catch: Sub-bass is about 7.2 dB under target and bass is 2.6 dB low, so kick drums and bass lines lack weight and rumble.
Buy the ISN Audio Neo 3. It is rated higher for sound quality than the Etymotic ER4XR and costs less, so it is the default pick unless a specific strength of the other one matters more to you.
Looking for alternatives? See the complete Headphones rankings.
A published AutoEQ preset corrects its response toward the Harman target, so a few minutes of EQ setup closes most of the gap.
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Upper mids sit within 0.5 dB of the Harman target and low mids within 0.4 dB, so vocals and instruments come through clearly and naturally.
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Specifications Side By Side
| ISN Audio Neo 3 | Etymotic ER4XR | |
|---|---|---|
| Price | 99.00 | $299.00 |
| Ranked | #1054 of 1369 in In-Ear Headphones | #1060 of 1369 in In-Ear Headphones |
| Form Factor | In-ear | In-ear |
| Back | Closed | Closed |
| Harman Preference Score | 63 (median of 6 squig.link measurements, calibrated to AutoEQ) | 62 (measured by oratory1990, via AutoEQ) |
| Deviation From Target | 2.70 dB standard deviation | 3.06 dB standard deviation |
| Tonal Tilt | -0.70 (negative is warmer, positive brighter) | +0.61 (negative is warmer, positive brighter) |
| Sub-bass Extension | Within 6 dB of target down to 20 Hz (-0.9 dB at 30 Hz) | Falls 6 dB below target at 47 Hz (-7.0 dB at 30 Hz) |
| Connection | Wired | Wired |
| Driver Type | Hybrid (2 Dynamic + 1 Planar) | Balanced armature |
| Drivers | 2 x 6mm dynamic drivers (1 low, 1 mid) + 1 x 5.8mm micro-planar driver (high) | 1 x balanced armature |
| Impedance | 15 ohms | 45 ohms |
| Sensitivity | 105 dB | - |
| Frequency Response | 10Hz - 20kHz | 20Hz - 16kHz (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 ISN Audio Neo 3 from avishai, flare, pw, soundcheck39, theaudiostore and treblewellxtended; the Etymotic ER4XR from aden, dchpgall, dentreviews, musicafe, precog and superreview, all via squig.link.
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