The KZ ES4 ranks #864 out of 909 total In-Ear Headphones for sound quality. See all Headphones rankings for every top pick.
Brand: KZ
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#864 KZ ES4 Discontinued eBay
Pros: Bass is lifted about 5.2 dB with extension to 20 Hz, giving kick drums and bass lines extra weight. Lower mids sit within about 0.7 dB of target, keeping voices and guitars natural. It uses 1 x 10mm dynamic + 1 x balanced armature with an easy 25 ohm load.
Cons: Discontinued, so it is mainly found used. Presence sits about 4.4 dB low with a 13 dB dip near 6.0 kHz, so vocals and instruments lose some bite. A 4.3 dB peak near 2.3 kHz can make cymbals and sibilance sound sharp. The 5.2 dB bass lift can sound boomy and mask midrange detail. A Harman score of 37 places it in the lower part of the in-ear rankings.
| Released | 2018 (8 years ago) |
|---|---|
| Connection | Wired |
| Deviation From Target | 4.54 dB standard deviation |
| Driver Type | Hybrid |
| Drivers | 1 x 10mm dynamic + 1 x balanced armature |
| Form Factor | In-ear |
| Frequency Response | 20Hz - 40kHz |
| Harman Preference Score | 37 (measured by oratory1990, via AutoEQ) |
| Impedance | 25 ohms |
| Sensitivity | 104 dB/mW |
| Sub-bass Extension | Within 6 dB of target down to 20 Hz (+4.1 dB at 30 Hz) |
| Tonal Tilt | -1.80 (negative is warmer, positive brighter) |
EQ preset to match the Harman target
Set a preamp of -6.0 dB, then add these filters in any parametric equalizer (Wavelet, Equalizer APO, Peace, or a player with parametric EQ). Calculated by AutoEQ from its measured frequency response.
| Filter | Frequency | Gain | Q |
|---|---|---|---|
| Low shelf | 105 Hz | -4.8 dB | 0.70 |
| Peak | 166 Hz | -4.5 dB | 1.12 |
| Peak | 5,554 Hz | +6.1 dB | 1.52 |
| Peak | 3,340 Hz | -5.4 dB | 1.03 |
| Peak | 7,947 Hz | +4.3 dB | 1.27 |
| High shelf | 10,000 Hz | -2.6 dB | 0.70 |
| Peak | 846 Hz | +3.1 dB | 1.21 |
| Peak | 2,197 Hz | -2.9 dB | 2.38 |
| Peak | 2,999 Hz | +2.4 dB | 4.34 |
| Peak | 299 Hz | -1.1 dB | 1.98 |
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