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ALTERNATIVES
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Sennheiser HD 660 S Review | 93 Data compared

Avg. price:~£380Form factor:over-earConnectivity:wiredBattery life:N/A hoursActive noise cancellation (ANC):no

Sennheiser HD 660 S Review: Compare 93 technical specifications and user reviews to see how this product ranks in the Headphones category and whether it is worth buying.

Sennheiser HD 660 S
6.1/10

Overall score

Score
6.1/ 10
✕
What it is
An overall evaluation of the headphones' quality, based on technical analyses and user reviews.
When it matters
When you need a quick reference to identify the best headphones on the market.
Score distribution
â–¼
<55-66-77-88-99-10
â–¼ Worse than 55% of models
Score components

80%

5.4

Technical score

20%

8.9

User score

â–¼Worse than 55% of headphones
6.8

Value for money

Value for money
6.8/ 10
✕
What it is
An indicator that combines the headphones' overall rating with their cost.
When it matters
When you are looking for headphones that offer a strong balance of performance, features, and price.
Score distribution
â–¼
<55-66-77-88-99-10
â–¼ Worse than 84% of models
Score components

70%

6.1

Overall score

30%

8.5

Price

â–¼Worse than 84%
5.4

Technical score

Technical score
5.4/ 10
✕
What it is
An assessment of technical performance for products in the Headphones category across these key areas: Sound, Calls & Controls, Connectivity, Features, Battery, Design.
When it matters
When you want to compare headphones based on technical performance and available features.
Score distribution
â–¼
<55-66-77-88-99-10
â–¼ Worse than 79% of models
Score components

52%

6.2

Sound

20%

4.0

Features

10%

6.4

Design

8%

4.0

Connectivity

6%

4.0

Battery

4%

4.9

Calls & Controls

â–¼Worse than 79%
8.9

User score

User score
8.9/ 10
✕
What it is
A rating that combines user reviews and the total number of reviews received by the headphones.
When it matters
When you want to understand how headphones perform in real listening and how reliable they are in terms of comfort, audio quality, battery life, and long-term use.
Score distribution
â–¼
<55-66-77-88-99-10
★ Better than 91% of models
Score components

70%

9.2

User ratings

30%

8.2

Number of reviews

Based on ratings from across the web.
★Better than 91%
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  • sennheiser-hd-660-s
  • sennheiser-hd-660-s
sennheiser-hd-660-s
sennheiser-hd-660-s
sennheiser-hd-660-s
Where to buy
*As an Amazon Associate, we earn from qualifying purchases.
Best rankings
Available: ranking among products currently available (including other versions of this product).All: ranking among all products in the database.
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Technical Specifications of pair of headphones Sennheiser HD 660 S

Technical score
Technical score
5.4/ 10
✕
What it is
An assessment of technical performance for products in the Headphones category across these key areas: Sound, Calls & Controls, Connectivity, Features, Battery, Design.
When it matters
When you want to compare headphones based on technical performance and available features.
Score distribution
â–¼
<55-66-77-88-99-10
â–¼ Worse than 79% of models
Score components:

52%

6.2

Sound

20%

4.0

Features

10%

6.4

Design

8%

4.0

Connectivity

6%

4.0

Battery

4%

4.9

Calls & Controls

5.4
User score
User score
8.9/ 10
✕
What it is
A rating that combines user reviews and the total number of reviews received by the headphones.
When it matters
When you want to understand how headphones perform in real listening and how reliable they are in terms of comfort, audio quality, battery life, and long-term use.
Score distribution
â–¼
<55-66-77-88-99-10
★ Better than 91% of models
Score components

70%

9.2

User ratings

30%

8.2

Number of reviews

Based on ratings from across the web.
8.9
Popularity
Popularity
8.2/ 10
✕
What it is
An indicator based on the number of reviews received by the headphones.
When it matters
When you prefer headphones that have already been chosen and reviewed by many other users.
Score distribution
â–¼
<55-66-77-88-99-10
â–² Better than 78% of models
Popularity:
Sennheiser HD 660 S has a popularity score of 8.2 points, which is higher than that of 78.1% of products in this category.
8.2
Value for money
Value for money
6.8/ 10
✕
What it is
An indicator that combines the headphones' overall rating with their cost.
When it matters
When you are looking for headphones that offer a strong balance of performance, features, and price.
Score distribution
â–¼
<55-66-77-88-99-10
â–¼ Worse than 84% of models
Score components:

70%

6.1

Overall score

30%

8.5

Price

6.8
Active noise cancellation (ANC)
no
This pair of headphones does not support active noise cancellation. 27.5% of headphones support active noise cancellation.
Driver type
dynamic
Driver size
42 mm
Market range: <10 mm – >50 mm
This pair of headphones uses a driver size of 42 mm, larger driver size than 82.2% of headphones and equal to 0.7% of headphones.
Number of drivers
1
Market range: <1 – >4
This pair of headphones uses 1 drivers, fewer drivers than 4% of headphones and equal to 96% of headphones.
Lowest frequency
9 Hz
Market range: <5 Hz – >20 Hz
This pair of headphones reaches a lowest frequency of 9 Hz, lower lowest frequency than 79.8% of headphones and equal to 0.4% of headphones.
Show more
Noise-canceling microphone
no
This pair of headphones does not support a noise-canceling microphone. 39% of headphones support noise-canceling microphones.
Can be used as a headset
yes
This pair of headphones is headset-ready, 84.8% is not. 15.2% of headphones can be used as headsets.
Number of microphones
0
Market range: <0 – >4
This pair of headphones has 0 microphones, fewer microphones than 73.2% of headphones and equal to 26.9% of headphones.
Boom microphone
no
This pair of headphones does not include a boom microphone. 13.5% of headphones have a boom microphone.
Microphone SNR
N/A
Show more
Connectivity
wired
This pair of headphones supports wired connectivity, less flexible connectivity than 49.2% of headphones and equal to 50.8% of headphones.
Bluetooth version
N/A
Maximum Bluetooth range
N/A
Audio latency
N/A
Multipoint support
no
This pair of headphones does not support multipoint. 30.6% of headphones support multipoint.
Show more
Ambient sound mode
no
This pair of headphones does not offer ambient sound mode. 24.9% of headphones support ambient sound mode.
EQ support
no
This pair of headphones does not support EQ customization. 23.2% of headphones support EQ.
Companion app
no
This pair of headphones does not work with a companion app. 21.6% of headphones support companion apps.
Adjustable ANC levels
N/A
Voice assistant support
no
This pair of headphones does not support voice assistants. 60.9% of headphones support voice assistants.
Show more
Battery life
N/A
Battery life with ANC
N/A
Charging time
N/A
Quick charge
no
This pair of headphones does not support quick charging. 33.1% of headphones support quick charge.
Battery capacity
N/A
Show more
Brand name
Sennheiser
Form factor
over-ear
Weight
260 g
Market range: <14 g – >340 g
This pair of headphones weighs 260 g, heavier than 65.6% of headphones and equal to 2.2% of headphones.
Acoustic design
open-back
Clamp force
6
Market range: <2.5 – >6.1
This pair of headphones has a clamp force of 6, higher clamp force than 88.7% of headphones and equal to 1.2% of headphones.
Show more

Sennheiser HD 660 S vs the average pair of headphones

246810TotalDesignSoundBatteryConnectivityCalls & ControlsFeatures
  • Hi-Res Audio certification
    This pair of headphones has Hi-Res Audio certification, the average pair of headphones does not. 23.1% of headphones are Hi-Res Audio certified.
  • Spatial audio support
    This pair of headphones supports spatial audio, the average pair of headphones does not. 15.9% of headphones support spatial audio.
  • 2 mm larger driver size
    This pair of headphones uses a larger driver size than the average pair of headphones (42 mm vs 40 mm). The average headphones use a driver size of 40 mm.
    42 mm vs 40 mm
  • 21,500 Hz higher treble extension
    This pair of headphones has a higher highest frequency than the average pair of headphones (41,500 Hz vs 20,000 Hz). The average headphones reach a highest frequency of 20,000 Hz.
    41,500 Hz vs 20,000 Hz
  • 0.26 % lower distortion
    This pair of headphones has a lower total harmonic distortion than the average pair of headphones (0 % vs 0.3 %). The average headphones have total harmonic distortion of 0.3 %.
    0.04 % vs 0.3 %
  • 9 Hz lower bass extension
    This pair of headphones has a lower lowest frequency than the average pair of headphones (9 Hz vs 18 Hz). The average headphones reach a lowest frequency of 18 Hz.
    9 Hz vs 18 Hz
  • 10 mm more spacious earcup height
    This pair of headphones offers more spacious earcup height than the average pair of headphones (70 mm vs 60 mm). The average headphones offer an inner earcup height of 60 mm.
    70 mm vs 60 mm
  • 1.8 m longer cable length
    This pair of headphones offers a more useful cable length than the average pair of headphones (3 m vs 1.2 m). The average headphones have a cable length of 1.2 m.
    3 m vs 1.2 m
  • 11.3% higher user score
    User score
    8.9/ 10
    ✕
    What it is
    A rating that combines user reviews and the total number of reviews received by the headphones.
    When it matters
    When you want to understand how headphones perform in real listening and how reliable they are in terms of comfort, audio quality, battery life, and long-term use.
    Score distribution
    â–¼
    â–¼
    <55-66-77-88-99-10
    Sennheiser HD 660 S
    the average pair of headphones
    Sennheiser HD 660 S has a higher user score than the average pair of headphones (8.9 vs 8).
    8.9 vs 8
  • 10 mm more spacious earcup height
    This pair of headphones offers more spacious earcup height than the average pair of headphones (70 mm vs 60 mm). The average headphones offer an inner earcup height of 60 mm.
    70 mm vs 60 mm
  • 1.8 m longer cable length
    This pair of headphones offers a more useful cable length than the average pair of headphones (3 m vs 1.2 m). The average headphones have a cable length of 1.2 m.
    3 m vs 1.2 m
  • Open-back design
    This pair of headphones uses an open-back design, while the average pair of headphones does not. 9.1% of headphones have an open-back design.
  • Hi-Res Audio certification
    This pair of headphones has Hi-Res Audio certification, the average pair of headphones does not. 23.1% of headphones are Hi-Res Audio certified.
  • Spatial audio support
    This pair of headphones supports spatial audio, the average pair of headphones does not. 15.9% of headphones support spatial audio.
  • 2 mm larger driver size
    This pair of headphones uses a larger driver size than the average pair of headphones (42 mm vs 40 mm). The average headphones use a driver size of 40 mm.
    42 mm vs 40 mm
  • 21,500 Hz higher treble extension
    This pair of headphones has a higher highest frequency than the average pair of headphones (41,500 Hz vs 20,000 Hz). The average headphones reach a highest frequency of 20,000 Hz.
    41,500 Hz vs 20,000 Hz
  • 0.26 % lower distortion
    This pair of headphones has a lower total harmonic distortion than the average pair of headphones (0 % vs 0.3 %). The average headphones have total harmonic distortion of 0.3 %.
    0.04 % vs 0.3 %
  • 9 Hz lower bass extension
    This pair of headphones has a lower lowest frequency than the average pair of headphones (9 Hz vs 18 Hz). The average headphones reach a lowest frequency of 18 Hz.
    9 Hz vs 18 Hz
  • 2 dB/mW higher sensitivity
    This pair of headphones has a higher sensitivity than the average pair of headphones (104 dB/mW vs 102 dB/mW). The average headphones have sensitivity of 102 dB/mW.
    104 dB/mW vs 102 dB/mW
  • No passive noise reduction
    This pair of headphones does not offer passive noise reduction, while the average pair of headphones does. 82.6% of headphones have passive noise reduction.
  • No voice assistant support
    This pair of headphones does not support voice assistants, the average pair of headphones does. 60.8% of headphones support voice assistants.
  • 19.3% higher weight
    This pair of headphones is heavier than the average pair of headphones (260 g vs 218 g). The average pair of headphones weighs 218 g.
    260 g vs 218 g
  • 1.7 higher clamp force
    This pair of headphones has a higher clamp force than the average pair of headphones (6 vs 4.3). The average headphones have a clamp force of 4.3.
    6 vs 4.3
  • No battery indicator
    This pair of headphones does not show battery level clearly, while the average pair of headphones does. 56.3% of headphones have a battery level indicator.
  • 4.22x more expensive
    Sennheiser HD 660 S is more expensive than the average pair of headphones (£380 vs £90).
    £380 vs £90
  • 1 fewer microphones
    This pair of headphones has fewer microphones than the average pair of headphones (0 vs 1). The average headphones have 1 microphones.
    0 vs 1
  • Tangle-prone cable
    This pair of headphones uses a tangle-prone cable, while the average pair of headphones is easier to manage. 64.2% of headphones use a tangle-free cable.
  • 4.22x more expensive
    Sennheiser HD 660 S is more expensive than the average pair of headphones (£380 vs £90).
    £380 vs £90
  • 6.3% worse value for money
    Sennheiser HD 660 S has worse value for money than the average pair of headphones (6.84 vs 7.3).
    6.84 vs 7.27
  • 19.3% higher weight
    This pair of headphones is heavier than the average pair of headphones (260 g vs 218 g). The average pair of headphones weighs 218 g.
    260 g vs 218 g
  • 1.7 higher clamp force
    This pair of headphones has a higher clamp force than the average pair of headphones (6 vs 4.3). The average headphones have a clamp force of 4.3.
    6 vs 4.3
  • Tangle-prone cable
    This pair of headphones uses a tangle-prone cable, while the average pair of headphones is easier to manage. 64.2% of headphones use a tangle-free cable.
  • No travel bag
    This pair of headphones does not include a travel bag, the average pair of headphones does. 65.4% of headphones include a travel bag.
  • 4 mm tighter earcup width
    This pair of headphones has tighter earcup width than the average pair of headphones (40 mm vs 44 mm). The average headphones offer an inner earcup width of 44 mm.
    40 mm vs 44 mm
  • No passive noise reduction
    This pair of headphones does not offer passive noise reduction, while the average pair of headphones does. 82.6% of headphones have passive noise reduction.
  • 0.5 dB looser channel balance
    This pair of headphones has a higher channel balance tolerance than the average pair of headphones (1 dB vs 0.5 dB). The average headphones have channel balance tolerance of 0.5 dB.
    1 dB vs 0.5 dB
  • No battery indicator
    This pair of headphones does not show battery level clearly, while the average pair of headphones does. 56.3% of headphones have a battery level indicator.
  • 1 fewer microphones
    This pair of headphones has fewer microphones than the average pair of headphones (0 vs 1). The average headphones have 1 microphones.
    0 vs 1
  • No voice assistant support
    This pair of headphones does not support voice assistants, the average pair of headphones does. 60.8% of headphones support voice assistants.

Video reviews

Hands-on testing, unboxing, and real-world video evaluations

8.0
Gadget Generations
≈ estimated
03/07/2022
Week-long review · sound, bass and soundstage
Verdict
Sennheiser HD 660 S is a pretty good headphone for listeners who love smooth, vocal-focused mids.
8.0
Headphone PH
≈ estimated
12/01/2022
Hands-on review · sound tests, amp use and rival comparisons
Verdict
Sennheiser HD 660 S is a very good choice for listeners not chasing the high end, though it benefits from an amplifier.
9.0
the Honest Audiophile
≈ estimated
30/03/2021
Comparison review · sound against rival open-back and closed-back headphones
Verdict
Sennheiser HD 660 S is highly recommended if you love the HD 600 but want a bigger, airier sound.
8.0
TotallydubbedHD
≈ estimated
22/07/2020
Hands-on review · soundstage, comfort and gaming tests
Verdict
Sennheiser HD 660 S has an excellent soundstage and vocals, but clamp force and mid-bass control hold it back for some listeners.
6.0
The Headphone Show
≈ estimated
01/07/2020
Hands-on review · sound, EQ and value comparison
Verdict
Sennheiser HD 660 S is tonally strong and an upgrade, but hard to recommend at this price against cheaper options.
4.0
Max Settings
≈ estimated
09/06/2019
Hands-on review · comparison with older 300 ohm Sennheisers
Verdict
Sennheiser HD 660 S is too expensive for the small gain over older 300 ohm models and is not a worthy HD 650 successor.
4.0
chuckolatte
≈ estimated
18/02/2019
Hands-on review · sound and value comparison
Verdict
Sennheiser HD 660 S sounds dark and airless with a narrow stage, and the cheaper alternatives are the better buy.
8.0
Streaky
≈ estimated
08/02/2019
Hands-on review · sound, build and connectors
Verdict
Sennheiser HD 660 S is balanced, detailed and well built, and worth a look in its price band despite a closed-in stereo image.
9.0
Joshua Valour
✓ explicit
11/06/2018
Hands-on review · tube amp tests, imaging and sound comparisons
Verdict
Sennheiser HD 660 S is an excellent, neutral headphone for professionals and music makers, though it is a big investment.
9.0
Damir Franc
≈ estimated
10/03/2018
Hands-on review · four weeks of use
Verdict
Sennheiser HD 660 S is a balanced, comfortable reference headphone that is hard to beat at this level, though not outstanding in any single area.
7.0
metal571
≈ estimated
17/12/2017
Hands-on review · comparison with HD 600 and pad wear effects
Verdict
Sennheiser HD 660 S has the best detail retrieval in its line, but it is too expensive at list price and needs a lower street price.
6.0
InnerFidelity
≈ estimated
16/12/2017
Full review · fit, sound comparison and amp pairing
Verdict
Sennheiser HD 660 S is a good headphone but not a legendary successor, and older models remain the better choice.
More graded video reviews (3)
creator’s own scoreestimated by us

Expert reviews

In-depth analysis and verdict from leading tech publications

S
stereophile.com
16/12/2017
Summary of the review
Sennheiser HD 660 S Over-Ear Open Headphones
gavinsgadgets.com
13/01/2018
Hands-on review · Open-back headphones
Verdict
The Sennheiser HD 660 S is a detailed, wide-soundstage open-back pair with precise positioning and speed, but it needs a powerful amplifier to sound its best.
theaudiophileman.com
22/02/2018
Hi-fi review · Amplifier pairing
Verdict
The Sennheiser HD 660 S is an easy-to-drive open pair with broad staging and detailed mids, a dependable choice for vinyl and CD systems.
H
headfonia.com
03/04/2018
Summary of the review
Sennheiser HD 660S - Review
stereonet.com
21/05/2018
Long-term listening · Open-back classic
Verdict
The Sennheiser HD 660 S is a detailed open-back that suits vocals and acoustic music and drives easily from phones, but can sound shouty.
expertreviews.co.uk
04/06/2018
Long-term review · Open-back reference
Verdict
The Sennheiser HD 660 S is a fuller, more bass-driven take on the HD 600 line that suits electronica and jazz but dulls air in orchestral recordings.
techpowerup.com
18/09/2018
Long listening test · Open-back headphones
Verdict
The Sennheiser HD 660 S is an excellent all-genre open-back that stays smooth at high volume, but its bass fades well before the advertised 10 Hz.
loudersound.com
01/06/2023
Review · Wired open-back headphones
Verdict
The Sennheiser HD 660S is a comfortable, lightweight open-back with clear, spacious sound, though its bass lacks punch and the newer HD 660S2 improves it.
soundguys.com
28/11/2024
Lab and listening test · Open-back
Verdict
The Sennheiser HD 660S suits a quiet room for editing and critical listening, as it is light and comfortable but leaks sound and isolates poorly.
R
rtings.com
27/06/2024
Summary of the review
Sennheiser HD 660 S Headphones Review
enjoythemusic.com
01/05/2018
Hands-on review · Open-back headphones
Verdict
The Sennheiser HD 660 S is a smooth, sweet-sounding open-back that works well with portable players, though it scales less well than 300-ohm models.
majorhifi.com
31/10/2017
Review · Open-back reference headphones
Verdict
The Sennheiser HD 660 S is the strongest of the HD 600 line so far, with crisp bass and easy drive, though it needs an amp for loud listening.
homedjstudio.com
16/10/2022
Hands-on test · Studio and home use
Verdict
The Sennheiser HD 660 S is a fatigue-free all-rounder for studio mixing and relaxed listening, but its weak sub-bass disappoints bass fans.
headphonecheck.com
06/02/2018
Hands-on test · Home hi-fi listening
Verdict
The Sennheiser HD 660 S is a neutral, spacious headphone with tight bass and very low distortion, best for home hi-fi with a proper amp.
lbtechreviews.com
31/08/2020
Listening test · Reference open headphones
Verdict
The Sennheiser HD 660S is a comfortable, well-balanced open headphone that plays well from simple amps to high-end hi-fi, but its bass lacks depth.
kopfhoerer.de
18/06/2020
Review · Updated open-back model
Verdict
The Sennheiser HD 660 S (2019) is a distortion-free open headphone with excellent speech clarity, but its firm clamp and slightly muted highs limit long sessions.
hifi.de
20/04/2021
Test · Open-back home listening
Verdict
The Sennheiser HD 660S is a natural, fatigue-free open headphone for relaxed listening at home, but it is not suited to buses and trains.
lowbeats.de
13/12/2018
Review · Open-back high-end
Verdict
The Sennheiser HD 660 S is a tight, transparent open headphone that sounds close to good loudspeakers, but phones give too little volume to drive it.
fairaudio.de
05/06/2018
Hifi test · Open-back comparison
Verdict
The Sennheiser HD 660 S is a more direct open headphone with clearer voices than the HD 650, but its stage feels smaller than the HD 800 S.
computerbild.de
03/01/2021
Test · Home listening headphone
Verdict
The Sennheiser HD 660 S is a very comfortable, precise headphone that sounds warm and forgiving, but it is too big for travel and weak on phones.

Third-party reviews

Based on ratings from across the web.
Reviews last updated: November 2026 · How we calculate this

What customers like about Sennheiser HD 660 S

  • Exceptional midrange clarity, providing natural and lifelike vocals and instrumentals
  • Improved detail retrieval and resolution compared to its predecessors (HD 600 and HD 650)
  • Highly comfortable and lightweight design suitable for long listening sessions once broken in
  • Easier to drive than previous 600-series models due to lower 150-ohm impedance
  • Excellent imaging and instrument separation, making them effective for critical listening and gaming
  • Durable, proven build quality with easily replaceable parts like earpads and cables

What customers don't like about Sennheiser HD 660 S

  • Noticeable lack of sub-bass extension, with significant roll-off starting around 80Hz
  • Relatively narrow soundstage that can feel intimate or 'in-your-head' compared to competitors
  • High out-of-the-box clamping force that may be uncomfortable until the headband stretches
  • Muffled or 'veiled' treble for some listeners, lacking the 'air' or sparkle found in brighter headphones
  • Questionable value at original MSRP when compared to the much cheaper HD 6XX or Sundara
  • Pads wear out relatively quickly and require periodic replacement to maintain sound quality

Verdict

The Sennheiser HD 660 S is a high-end, open-back dynamic headphone featuring a 150-ohm impedance and a frequency response of 10 Hz to 41,000 Hz, driven by specially developed transducers with lightweight aluminium voice coils. Known for its natural, detailed, and non-fatiguing sound signature, it excels with a lush midrange, smooth treble, and exceptional instrument separation, all housed in a lightweight 260g chassis with comfortable velour ear pads. While its lower impedance makes it more versatile for use with mobile devices than its predecessors, its sub-bass rolls off significantly below 80 Hz, and the soundstage is relatively narrow with a strong initial clamping force.

Compare Sennheiser HD 660 S with other products in the Headphones category

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