The Superlux HD 668B ranks #27 out of 308 total Over-Ear Headphones for sound quality. See all Headphones rankings for every top pick.
Brand: Superlux
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#27 Superlux HD 668B: $51.21 Amazon $51.21 eBay
Pros: Measured response gives it an excellent Harman preference score of 89 with a 1.75 dB spread, and its mids sit within about 0.5 dB of target, so vocals and instruments sound natural. It uses 1 x 50mm dynamic.
Cons: A 7.3 dB peak near 5.6 kHz can make cymbals and sibilance sound sharp. Sub-bass is 11.5 dB short at 30 Hz, so deep bass lacks rumble.
| Back | Open |
|---|---|
| Connection | Wired |
| Deviation From Target | 1.75 dB standard deviation |
| Driver Type | Dynamic |
| Drivers | 1 x 50mm dynamic |
| Form Factor | Over-ear |
| Frequency Response | 10Hz - 30kHz |
| Harman Preference Score | 89 (measured by oratory1990, via AutoEQ) |
| Impedance | 56 ohms |
| Sensitivity | 98 dB/mW |
| Sub-bass Extension | Falls 6 dB below target at 42 Hz (-11.5 dB at 30 Hz) |
| Tonal Tilt | +0.19 (negative is warmer, positive brighter) |
| Weight | 0.5 lbs (222 g) |
EQ preset to match the Harman target
Set a preamp of -6.1 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 | +6.2 dB | 0.70 |
| Peak | 84 Hz | -4.5 dB | 0.92 |
| Peak | 4,513 Hz | +4.9 dB | 2.16 |
| Peak | 5,665 Hz | -8.5 dB | 4.02 |
| Peak | 41 Hz | +1.4 dB | 1.57 |
| High shelf | 10,000 Hz | -0.3 dB | 0.70 |
| Peak | 573 Hz | +1.2 dB | 1.98 |
| Peak | 1,417 Hz | +1.5 dB | 2.41 |
| Peak | 2,114 Hz | -0.9 dB | 2.68 |
| Peak | 7,753 Hz | -1.2 dB | 4.40 |
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