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Image © SennheiserSennheiser HD 660s
At a glance
- Brand
- Sennheiser
- Type
- Over-Ear
- Fit
- open
- Connection
- Wired
- Noise cancelling
- No
- Released
- 2017
Score breakdowngreat overall
Sound8.2
Value5.5
The new HD 660 S lets you enjoy sophisticated audiophile sound in even more listening situations. The successor of the legendary HD 650 excels with the improved performance of its new transducer design. Thanks to its lower impedance, it delivers reference-class sound also when connected to hi-res mobile players, thus offering much greater versatility.
The HearWiki takeAI-condensed
The Sennheiser HD 660 S is a wired, open-back dynamic headphone that delivers a neutral, mid-focused sound with accurate vocals and instruments, though bass impact is limited. It offers a comfortable fit and a wide soundstage, but its open design provides virtually no isolation, making it best suited for quiet home listening. While it performs well with a range of music, it benefits from decent amplification to reach its full potential.
What works
- Accurate and natural midrange for vocals and instruments
- Comfortable for long listening sessions
- Wide soundstage with good imaging
- Detachable cable and balanced connection option
What doesn't
- Very poor isolation due to open-back design
- Limited bass impact
- Upper mids can sound harsh at higher volumes
- Requires suitable amplification for best performance
Paraphrased from published reviews & specs - not an original hands-on test. Our AI disclosure.
Specifications
| Driver | 42 mm dynamic |
|---|---|
| Driver type | dynamic |
| Driver size | 42 mm |
| Drivers per side | 1 |
| Frequency response | 10 Hz - 41 kHz |
| Impedance | 150 Ω |
| Sensitivity | 104 dB/mW |
| Sensitivity (dB/Vrms) | 110 |
Audio
| Driver | 42 mm dynamic |
|---|---|
| Driver type | dynamic |
| Driver size | 42 mm |
| Drivers per side | 1 |
| Frequency response | 10 Hz - 41 kHz |
| Impedance | 150 Ω |
| Sensitivity | 104 dB/mW |
| Sensitivity (dB/Vrms) | 110 |
Features
| Active noise cancelling | No |
|---|
Design
| Weight | 260 g |
|---|---|
| Detachable cable | Yes |
| Balanced connection | Yes |
Where to buy
Retailers we matched to this exact model. Prices are periodic snapshots - the link always opens the retailer's current listing.
What the reviews said
4 source(s) feeding this product's score.
What YouTube reviewers say
Video reviews we found, each condensed to its verdict. They do feed the HearWiki score, at a measured weight below what a published written review carries.
12:30Sennheiser HD660s Review - Is this better than the Sundara?
The reviewer compares the Sennheiser HD 660s to the Hifiman Sundara and concludes that the Sundara is the better choice due to its superior bass extension, soundstage, and resolution, despite the HD 660s having good build quality and imaging. The HD 660s is seen as overpriced given the existence of the cheaper HD 6xx, and its soundstage is notably narrow. The reviewer recommends the Sundara for most users, though notes the HD 660s may pair better with certain high-end tube amplifiers.
MixedWatch on YouTube
6:29Sennheiser HD660S - REVIEW
The reviewer finds the HD 660S to be an excellent headphone with superior detail retrieval and a slightly wider soundstage compared to the HD 600/650 line, and notes it is easier to drive. However, he argues that the premium price is hard to justify given the modest performance gain over cheaper alternatives like the HD 580, making it a great but not necessarily cost-effective choice.
MixedWatch on YouTube
10:36Chrono Reviews the Sennheiser HD660s - A legend at a premium
The reviewer finds the HD 660s to be his favorite in the HD 600 series, praising its smooth midrange, good resolution, and improved imaging over predecessors. However, he criticizes the lack of sub-bass, a narrow soundstage, and a peak at 5.5 kHz that adds a slightly boxy tone. He ultimately struggles to recommend it at its $499 MSRP due to strong competition from cheaper alternatives like the HD 6XX, suggesting it's only competitive when discounted.
MixedWatch on YouTube
4:26Review and Buying Guide for the Sennheiser HD 660S
The reviewer praises the HD 660S for its accurate and dynamic bass, lush and precise mids, and non-fatiguing treble, along with a wide soundstage and detailed imaging. They highlight the comfortable build and note that pairing with a tube amplifier can further enhance clarity. The headphones are recommended for studio professionals, gamers, and critical listeners.
PositiveWatch on YouTube
Summaries are AI condensations of each video's own conclusion, not transcripts. Titles, thumbnails and view counts belong to their channels.
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