Short answer: the Fir Audio e12. It ranks #943 of 1291 in-ear headphones by sound quality, rated 3.2/5, at $1,799. The 64 Audio Nio ranks #976, rated 3.1/5, at $1,699, $100 cheaper, a saving that is not big enough to make up the sound-quality gap.
What the Fir Audio e12 does well: A big, energetic V shaped tuning in HypetheSonics’ measurement, with sub-bass about 4 dB and bass about 5.5 dB above target for heavy, physical kick drums and synth lines. Watch for: A 9.3 dB peak near 8.1 kHz and treble about 5 dB above target from 6 to 10 kHz can make cymbals and sibilance sharp and fatiguing at higher volume.
The case for the 64 Audio Nio: A warm, bass-forward tuning with sub-bass about 2 dB and mid-bass about 3 dB above target gives kick drums and bass lines real weight, and the response holds within 6 dB of target all the way down to 20 Hz. The catch: Across 7 hobbyist measurements on squig.link it reaches a preference score of only 63, held back by a 5.8 dB dip near 3.2 kHz and a presence region about 3.4 dB low, which pushes vocals and guitars back and dulls their edge.
Buy the Fir Audio e12. It is rated higher for sound quality, and the $100 saving on the 64 Audio Nio is not enough to make up the difference.
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A big, energetic V shaped tuning in HypetheSonics’ measurement, with sub-bass about 4 dB and bass about 5.5 dB above target for heavy, physical kick drums and synth lines.
Audio46 $1,799.00 eBay
A warm, bass-forward tuning with sub-bass about 2 dB and mid-bass about 3 dB above target gives kick drums and bass lines real weight, and the response holds within 6 dB of target all the way down to 20 Hz.
Bloom Audio $1,699.00 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
| Fir Audio e12 | 64 Audio Nio | |
|---|---|---|
| Price | $1,799.00 | $1,699.00 |
| Ranked | #943 of 1291 in In-Ear Headphones | #976 of 1291 in In-Ear Headphones |
| Form Factor | In-ear | In-ear |
| Back | Closed | Closed |
| Harman Preference Score | 64 (measured by HypetheSonics, via AutoEQ) | 63 (median of 7 squig.link measurements, calibrated to AutoEQ) |
| Deviation From Target | 2.66 dB standard deviation | 2.51 dB standard deviation |
| Tonal Tilt | -0.62 (negative is warmer, positive brighter) | -1.01 (negative is warmer, positive brighter) |
| Sub-bass Extension | Within 6 dB of target down to 20 Hz (+3.5 dB at 30 Hz) | Within 6 dB of target down to 20 Hz (+1.0 dB at 30 Hz) |
| Connection | Wired | Wired |
| Driver Type | Dynamic | Hybrid (1 dynamic + 8 balanced armature) |
| Drivers | 1 x 12mm dynamic | 1 x 9mm dynamic + 8 x balanced armature |
| Impedance | 16 ohms | 6 ohms |
| Frequency Response | 20Hz - 20kHz (Manufacturer specified) | 10Hz - 20kHz (Manufacturer specified) |
| Built-in Microphone | No | - |
| Sensitivity | - | 108 dB/mW |
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 Fir Audio e12 from aftersound, eliseaudio, jaytiss, sl0the, tgx78, theaudiostore and treblewellxtended; the 64 Audio Nio from adri-n, bloomaudio, ekaudio, hu-fi, listener, precog and superreview, all via squig.link.
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