Short answer: the EPZ 550. Both are rated 4.1/5 for sound quality (#330 and #344 of 1291 in-ear headphones), and the EPZ 550 costs $519.99 against $539 for the YU9 Audio Que, so with nothing between them on sound quality, price settles it.
What the EPZ 550 does well: The median of 7 hobbyist measurements gives it a very good Harman preference score of 75 with a 1.85 dB spread. The tradeoff: Presence sits about 4.5 dB low with a 6.1 dB dip near 6.1 kHz, so vocals and instruments lose some bite.
Why pick the YU9 Audio Que: The median of 22 hobbyist measurements gives it a very good Harman preference score of 75 with a 1.81 dB spread, and its mids sit within about 1.1 dB of target, so vocals and instruments sound natural. The tradeoff: Presence sits about 4.3 dB low with a 6.8 dB dip near 5.6 kHz, so vocals and instruments lose some bite.
Buy the EPZ 550. Both are rated the same for sound quality, and it costs $19.01 less than the YU9 Audio Que.
Still deciding? The full Headphones rankings cover every ranked option.
The median of 7 hobbyist measurements gives it a very good Harman preference score of 75 with a 1.85 dB spread.
Amazon $519.99 eBay
The median of 22 hobbyist measurements gives it a very good Harman preference score of 75 with a 1.81 dB spread, and its mids sit within about 1.1 dB of target, so vocals and instruments sound natural.
Hangout.Audio $539 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
| EPZ 550 | YU9 Audio Que | |
|---|---|---|
| Price | $519.99 | $539 |
| Ranked | #330 of 1291 in In-Ear Headphones | #344 of 1291 in In-Ear Headphones |
| Form Factor | In-ear | In-ear |
| Back | Closed | Closed |
| Harman Preference Score | 75 (median of 7 squig.link measurements, calibrated to AutoEQ) | 75 (median of 22 squig.link measurements, calibrated to AutoEQ) |
| Deviation From Target | 1.85 dB standard deviation | 1.81 dB standard deviation |
| Tonal Tilt | +0.07 (negative is warmer, positive brighter) | -0.44 (negative is warmer, positive brighter) |
| Sub-bass Extension | Within 6 dB of target down to 20 Hz (-4.3 dB at 30 Hz) | Within 6 dB of target down to 20 Hz (-1.4 dB at 30 Hz) |
| Connection | Wired | Wired |
| Driver Type | Balanced armature | Hybrid |
| Drivers | 5 x balanced armature | 1 x dynamic + 3 x balanced armature |
| Sensitivity | 105 dB | 126 dB/Vrms |
| Frequency Response | 20Hz - 20kHz (Manufacturer specified) | - |
| Built-in Microphone | No | - |
| Impedance | - | 9 ohms |
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 EPZ 550 from atechreviews, audioamigo, awsmdanny, bassaudio, hbb, jaytiss and koi; the YU9 Audio Que from aden, aftersound, animagus, atechreviews, audioamigo, banzai1122, bassaudio, dl, doltonius, eliseaudio, enemyspider, flare, jaytiss, koi, lestat, listener, practiphile, precog, pw, smirk, superreview and zerostresslevel, all via squig.link.
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