The Sennheiser HD 660 S ranks #236 out of 382 total Over-Ear Headphones for sound quality. See all Headphones rankings for every top pick.
Brand: Sennheiser
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#236 Sennheiser HD 660 S Discontinued eBay
Newer model: the Sennheiser HD 660S2, ranked higher, rated 3.8/5, released Feb 2023. See every Sennheiser HD 660 generation.
Pros: Measured response gives it a solid Harman preference score of 69 with a 2.96 dB spread, and its mids sit within about 1.1 dB of target, so vocals and instruments sound natural.
Cons: Discontinued, so it is mainly found used. Sub-bass is 10.8 dB short at 30 Hz, so deep bass lacks rumble. Treble sits about 7.9 dB low, so it sounds a little dark.
| Released | 2017 (9 years ago) |
|---|---|
| Back | Open |
| Connection | Wired |
| Deviation From Target | 2.96 dB standard deviation |
| Driver Type | Dynamic |
| Form Factor | Over-ear |
| Frequency Response | 10Hz - 41kHz |
| Harman Preference Score | 69 (measured by oratory1990, via AutoEQ) |
| Impedance | 150 ohms |
| Sensitivity | 104 dB/Vrms |
| Sub-bass Extension | Falls 6 dB below target at 60 Hz (-10.8 dB at 30 Hz) |
| Tonal Tilt | -0.51 (negative is warmer, positive brighter) |
| Weight | 0.6 lbs (260g) |
EQ preset to match the Harman target
Set a preamp of -6.3 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 | +6.5 dB | 0.70 |
| Peak | 7,899 Hz | +6.5 dB | 0.68 |
| Peak | 178 Hz | -3.2 dB | 0.49 |
| Peak | 5,470 Hz | -7.3 dB | 4.40 |
| Peak | 1,222 Hz | -2.3 dB | 2.34 |
| High shelf | 10,000 Hz | -1.1 dB | 0.70 |
| Peak | 2,250 Hz | +1.3 dB | 3.58 |
| Peak | 3,380 Hz | -0.9 dB | 2.84 |
| Peak | 6,701 Hz | +1.2 dB | 6.00 |
| Peak | 784 Hz | -0.4 dB | 3.52 |
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