The Sennheiser HD 660S2 ranks #66 out of 165 total Over-Ear Headphones for sound quality. See all Headphones rankings for every top pick.
Brand: Sennheiser
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#66 Sennheiser HD 660S2: $479.95 B&H Photo Video eBay
Pros: Oratory1990’s measurement gives it a preference score of 78 with a smooth midrange, as the band from 200 Hz to 6 kHz stays within about 1.4 dB of the Harman target and the largest peak above 1.5 kHz is under 2 dB. Voices, strings and piano come across natural and free of harshness. The gently warm balance suits long listening sessions at home.
Cons: Sub-bass falls about 6.5 dB below target and is 6 dB short by 40 Hz, and an open back means bass is felt less and sound leaks out freely. A 7.9 dB dip near 9.3 kHz dulls cymbal shimmer, and its 300 ohm impedance with 104 dB/V sensitivity calls for a dedicated headphone amp. The cheaper Austrian Audio Hi-X65 rates the same.
| Released | Feb 2023 (3 years ago) |
|---|---|
| Back | Open |
| Built-in Microphone | No |
| Connection | Wired |
| Deviation From Target | 2.36 dB standard deviation |
| Driver Type | Dynamic |
| Drivers | 1 x 38mm dynamic |
| Form Factor | Over-ear |
| Frequency Response | 8Hz - 41.5kHz (Manufacturer specified) |
| Harman Preference Score | 78 (measured by oratory1990, via AutoEQ) |
| Impedance | 300 ohms |
| Sensitivity | 104 dB SPL/V |
| Sub-bass Extension | Falls 6 dB below target at 40 Hz (-7.4 dB at 30 Hz) |
| Tonal Tilt | -0.43 (negative is warmer, positive brighter) |
| Weight | 0.6 lbs (260 g) |
EQ preset to match the Harman target
Set a preamp of -6.4 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 | +7.6 dB | 0.70 |
| Peak | 98 Hz | -3.5 dB | 0.31 |
| Peak | 8,089 Hz | +4.7 dB | 0.53 |
| Peak | 5,567 Hz | -6.6 dB | 3.92 |
| Peak | 1,206 Hz | -2.0 dB | 2.46 |
| High shelf | 10,000 Hz | -3.8 dB | 0.70 |
| Peak | 2,218 Hz | +1.1 dB | 3.75 |
| Peak | 3,206 Hz | -1.2 dB | 3.51 |
| Peak | 4,367 Hz | +1.3 dB | 6.00 |
| Peak | 115 Hz | +0.1 dB | 1.26 |
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