Short answer: the FlipEars Aegis. It ranks #997 of 1369 in-ear headphones by sound quality, rated 3.2/5, at $479. The HiBy Crystal 6 ranks #1063, rated 3.0/5, at $459, $20 cheaper, which does not close the gap in sound quality.
Why pick the FlipEars Aegis: 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 HiBy Crystal 6: A lively V-shaped tuning with about 3.7 dB of extra bass and a treble lift of 5 to 6 dB above 6 kHz, which gives drums punch and cymbals plenty of sparkle. The tradeoff: Squig.link measurements show a 9.9 dB peak near 7.9 kHz, so sibilance and hi-hats can turn sharp and fatiguing at higher volumes.
Buy the FlipEars Aegis. It is rated higher for sound quality, and the $20 saving on the HiBy Crystal 6 is not enough to make up the difference.
Want more options? Browse the full 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.
Bloom Audio $479.00 eBay
A lively V-shaped tuning with about 3.7 dB of extra bass and a treble lift of 5 to 6 dB above 6 kHz, which gives drums punch and cymbals plenty of sparkle.
HiFiGo $459.00 eBayPrices on this page were last checked October 17, 2026 at 6:04 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.
As an eBay Partner, we may be compensated if you make a purchase.
Specifications Side By Side
| FlipEars Aegis | HiBy Crystal 6 | |
|---|---|---|
| Price | $479.00 | $459.00 |
| Ranked | #997 of 1369 in In-Ear Headphones | #1063 of 1369 in In-Ear Headphones |
| Form Factor | In-ear | In-ear |
| Back | Closed | Closed |
| Harman Preference Score | 64 (median of 9 squig.link measurements, calibrated to AutoEQ) | 62 (measured by crinacle, via AutoEQ) |
| Deviation From Target | 2.47 dB standard deviation | 3.17 dB standard deviation |
| Tonal Tilt | -0.90 (negative is warmer, positive brighter) | +0.21 (negative is warmer, positive brighter) |
| Sub-bass Extension | Within 6 dB of target down to 20 Hz (+1.3 dB at 30 Hz) | Within 6 dB of target down to 20 Hz (-5.0 dB at 30 Hz) |
| Connection | Wired | Wired |
| Driver Type | Hybrid (1 dynamic + 1 bone conduction) | Balanced armature |
| Drivers | 1 x dynamic driver + 1 x EarQuake bone conduction driver | 6 x balanced armature |
| Impedance | 8.2 ohms | 14 ohms |
| Sensitivity | 112 dB/mW | 107 dB/mW |
| Frequency Response | 5Hz - 20kHz | 5Hz - 60kHz (Manufacturer specified) |
| Built-in Microphone | - | No |
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 FlipEars Aegis from aden, audioamigo, bloomaudio, hbb, jaytiss, pw, sl0the, soundignity and therollo9; the HiBy Crystal 6 from hu-fi, practiphile, precog and superreview, all via squig.link.
Related Headphone Comparisons
More worthwhile head-to-heads for FlipEars Aegis: