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Sennheiser HD 660s2 Review | 93 Data compared

Avg. price in UK: ~£390
Avg. price in US: ~$480
Form factor: over-ear
Connectivity: wired
Battery life: N/A hours
Active noise cancellation (ANC): no

Sennheiser HD 660s2 review. Compare 93 technical specifications and user reviews to see how it ranks among headphones and if it is worth buying.

4.5

Poor

3.3

Poor

9.2

Exceptional

0.2
Gaming
Score components:
35.0%
0.0
Audio latency
25.0%
0.0
Low-latency game mode
20.0%
1.0
Can be used as a headset
12.0%
0.0
Noise-canceling microphone
8.0%
0.0
Battery life
1.0
Travel
Score components:
28.0%
1.0
Active noise cancellation (ANC)
24.0%
0.0
Battery life
18.0%
4.2
Weight
16.0%
0.0
Multipoint support
14.0%
0.0
Ambient sound mode
0.2
Calls
Score components:
28.0%
0.0
Noise-canceling microphone
24.0%
1.0
Can be used as a headset
18.0%
0.0
Multipoint support
16.0%
0.0
Battery life
14.0%
0.0
Companion app
2.3
Workout
Score components:
28.0%
4.2
Weight
24.0%
1.0
Water resistance
20.0%
4.0
IP rating
16.0%
0.0
Battery life
12.0%
1.0
Can be used as a headset

Best prices in UK

Best rankings

Verdict

The Sennheiser HD 660S2 is a high-end, open-back dynamic headphone featuring a 38mm transducer with an improved 300-ohm impedance and a frequency response of 8 Hz to 41.5 kHz. Key characteristics include a lightweight 260g design, plush velour ear pads, and a revised airflow system that lowers the resonant frequency to 70 Hz for enhanced sub-bass extension. Main pros include its natural, non-fatiguing sound signature, exceptional midrange clarity, and superior low-end impact compared to its predecessors. However, notable cons include its high initial clamping force, the requirement for a dedicated amplifier to reach its full potential due to the high impedance, and significant sound leakage inherent to its open-back design.

Technical Specifications of Sennheiser HD 660s2

Overall score

4.5

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Popularity

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.

Sound

3.5

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Active noise cancellation (ANC)

What it is: Reduces background noise using active technology

When it matters: When blocking office, travel, or aircraft noise is a priority.

Importance: HIGH

Driver type

What it is: Type of speaker driver technology used

When it matters: When the underlying sound character and driver technology matter to you.

Importance: MEDIUM

dynamic

Driver size

What it is: Diameter of the speaker driver unit

When it matters: When you want extra hardware context behind how the headphones may handle bass weight, scale, or overall presentation.

Importance: MEDIUM

Number of drivers

What it is: Total number of speaker drivers per earcup

When it matters: When multi-driver designs are part of your buying criteria.

Importance: LOW

Lowest frequency

What it is: Lowest audio frequency the headphones can reproduce

When it matters: When deeper bass extension matters for your music or movie listening.

Importance: MEDIUM

Good value: <=10 Hz

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Calls & Controls

1.1

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Noise-canceling microphone

What it is: Built-in microphone reduces background noise during calls

When it matters: When you take calls in busy spaces and want your voice to stay clearer.

Importance: MEDIUM

N/A

Can be used as a headset

What it is: Shows whether the headphones can handle voice chat and calls in addition to normal audio playback.

When it matters: When one pair needs to cover music, calls, meetings, and gaming chat.

Importance: MEDIUM

Number of microphones

What it is: Total number of built-in microphones

When it matters: When call pickup quality and beamforming support matter to you.

Importance: LOW

Good value: >=2

Boom microphone

What it is: Includes detachable boom microphone for voice clarity

When it matters: When you need stronger voice clarity for gaming, streaming, or work calls.

Importance: LOW

N/A

Microphone SNR

What it is: Signal-to-noise ratio of the microphone

When it matters: When call clarity matters and you want your voice picked up more cleanly instead of buried in background hiss.

Importance: LOW

Good value: >80 dB

N/A

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Connectivity

2.9

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Connectivity

What it is: Available connection methods (wired, wireless, Bluetooth, etc.)

When it matters: When the headphones need to match how you listen across wired and wireless devices.

Importance: HIGH

Bluetooth version

What it is: Version of Bluetooth technology supported

When it matters: When wireless stability, efficiency, and feature support matter more than treating Bluetooth as a box-check spec.

Importance: MEDIUM

Good value: >=5.0

N/A

Maximum Bluetooth range

What it is: Maximum wireless operating distance from source device

When it matters: When you move around rooms and want fewer dropouts from your source device.

Importance: LOW

Good value: >=10 m

N/A

Audio latency

What it is: Delay between audio and video in wireless mode

When it matters: When you watch video or play games and need sound to stay in sync.

Importance: HIGH

Good value: <60 ms

N/A

Multipoint support

What it is: Supports simultaneous connections to multiple devices

When it matters: When you switch often between a phone and a laptop during the day.

Importance: MEDIUM

N/A

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Features

2.7

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Ambient sound mode

What it is: Allows external sounds to pass through for awareness

When it matters: When you need to stay aware of traffic, voices, or announcements.

Importance: MEDIUM

N/A

EQ support

What it is: Allows customization of sound profile via equalizer

When it matters: When the stock tuning is not enough and you want to shape bass, mids, or treble to match your taste.

Importance: MEDIUM

Companion app

What it is: Dedicated mobile app for customization and updates

When it matters: When software customization, updates, and extra controls matter.

Importance: MEDIUM

N/A

Adjustable ANC levels

What it is: Allows adjustment of noise cancellation intensity levels

When it matters: When you move between quiet rooms, offices, streets, and public transport and do not want one ANC setting for every situation.

Importance: LOW

Good value: >=4

N/A

Voice assistant support

What it is: Compatible with voice assistants like Siri, Alexa, or Google Assistant

When it matters: When hands-free control is part of your daily routine.

Importance: LOW

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Battery

1.0

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Battery life

What it is: Playback time on a single charge

When it matters: When you commute, travel, or work long shifts and do not want charging breaks to interrupt listening.

Importance: HIGH

Good value: >45 hours

N/A

Battery life with ANC

What it is: Playback time with active noise cancellation enabled

When it matters: When you plan to keep noise cancellation on for most of the day.

Importance: HIGH

Good value: >40 hours

N/A

Charging time

What it is: Time required for a full battery charge

When it matters: When you often need the headphones ready again after short breaks.

Importance: MEDIUM

Good value: <=2 hours

N/A

Quick charge

What it is: Provides quick playback time with short charging period

When it matters: When a short top-up needs to deliver useful playback before you leave.

Importance: MEDIUM

N/A

Battery capacity

What it is: Total energy storage of the internal battery

When it matters: When you are estimating how much battery headroom the design may have before relying only on the official runtime claim.

Importance: MEDIUM

Good value: >=720 mAh

N/A

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Design

6.2

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Brand name

What it is: The manufacturer or brand of the product.

When it matters: When you prefer a specific ecosystem, support network, or design philosophy.

Importance: MEDIUM

Sennheiser

Form factor

What it is: Overall design type of the headphones (over-ear, on-ear, in-ear, etc.)

When it matters: When comfort, portability, and isolation depend on the overall headphone style.

Importance: HIGH

over-ear

Weight

What it is: Total weight of the headphones

When it matters: When long listening sessions make wearing comfort more important.

Importance: MEDIUM

Good value: <150 g

Acoustic design

What it is: Type of acoustic design (open-back, closed-back, semi-open)

When it matters: When you need the right balance of isolation, leakage, and soundstage.

Importance: HIGH

open-back

Clamp force

What it is: Amount of clamping pressure applied to the head

When it matters: When comfort and fit security matter during long sessions.

Importance: MEDIUM

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Sennheiser HD 660s2 vs the average headphone

Why is Sennheiser HD 660s2 better than the average headphone?

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Spatial audio support
Sennheiser HD 660s2 supports spatial audio, the average headphone does not. 30.7% of headphones support spatial audio.
What it is: Supports immersive surround sound playback
When it matters: When movies, games, and immersive mixes are part of your listening.
Importance: MEDIUM
Sennheiser HD 660s2 supports spatial audio, the average headphone does not. 30.7% of headphones support spatial audio.
10 Hz lower bass extension
Sennheiser HD 660s2 has a lower lowest frequency than the average headphone (8 Hz vs 18 Hz). The average headphones reach a lowest frequency of 18 Hz.
What it is: Lowest audio frequency the headphones can reproduce
When it matters: When deeper bass extension matters for your music or movie listening.
Importance: MEDIUM
Good value: <=10 Hz
Sennheiser HD 660s2 has a lower lowest frequency than the average headphone (8 Hz vs 18 Hz). The average headphones reach a lowest frequency of 18 Hz.8 Hz vs 18 Hz
21,500 Hz higher treble extension
Sennheiser HD 660s2 has a higher highest frequency than the average headphone (41,500 Hz vs 20,000 Hz). The average headphones reach a highest frequency of 20,000 Hz.
What it is: Highest audio frequency the headphones can reproduce
When it matters: When treble extension and overall frequency reach matter to you.
Importance: MEDIUM
Good value: >=24000 Hz
Sennheiser HD 660s2 has a higher highest frequency than the average headphone (41,500 Hz vs 20,000 Hz). The average headphones reach a highest frequency of 20,000 Hz.41500 Hz vs 20000 Hz
0.26 % lower distortion
Sennheiser HD 660s2 has a lower total harmonic distortion than the average headphone (0 % vs 0.3 %). The average headphones have total harmonic distortion of 0.3 %.
What it is: Percentage of harmonic distortion in audio output
When it matters: When cleaner sound reproduction matters at louder volumes.
Importance: LOW
Good value: <=1%
Sennheiser HD 660s2 has a lower total harmonic distortion than the average headphone (0 % vs 0.3 %). The average headphones have total harmonic distortion of 0.3 %.0.04 % vs 0.3 %
10 mm more spacious earcup height
Sennheiser HD 660s2 offers more spacious earcup height than the average headphone (70 mm vs 60 mm). The average headphones offer an inner earcup height of 60 mm.
What it is: Internal height of the earcup cavity
When it matters: When larger ears need enough space inside the earcups.
Importance: MEDIUM
Sennheiser HD 660s2 offers more spacious earcup height than the average headphone (70 mm vs 60 mm). The average headphones offer an inner earcup height of 60 mm.70 mm vs 60 mm
Open-back design
Sennheiser HD 660s2 uses an open-back design, while the average headphone does not. 9.3% of headphones have an open-back design.
What it is: Shows whether the headphones use an open-back housing that lets air and sound pass through more freely than a closed design.
When it matters: When you listen in quiet places and care more about spacious sound than blocking outside noise or preventing sound leakage.
Importance: MEDIUM
Sennheiser HD 660s2 uses an open-back design, while the average headphone does not. 9.3% of headphones have an open-back design.
14.4% higher user score
Sennheiser HD 660s2 has a higher user score than the average headphone (9.16 vs 8.000).
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.
Sennheiser HD 660s2 has a higher user score than the average headphone (9.16 vs 8.000).9.16 vs 8
0.6 m more useful cable length
Sennheiser HD 660s2 offers a more useful cable length than the average headphone (1.8 m vs 1.2 m). The average headphones have a cable length of 1.2 m.
What it is: Length of the supplied audio cable
When it matters: When your desk, TV, or audio setup needs more or less movement range.
Importance: LOW
Sennheiser HD 660s2 offers a more useful cable length than the average headphone (1.8 m vs 1.2 m). The average headphones have a cable length of 1.2 m.1.8 m vs 1.2 m
10 mm more spacious earcup height
Sennheiser HD 660s2 offers more spacious earcup height than the average headphone (70 mm vs 60 mm). The average headphones offer an inner earcup height of 60 mm.
Open-back design
Sennheiser HD 660s2 uses an open-back design, while the average headphone does not. 9.3% of headphones have an open-back design.
0.6 m more useful cable length
Sennheiser HD 660s2 offers a more useful cable length than the average headphone (1.8 m vs 1.2 m). The average headphones have a cable length of 1.2 m.
Spatial audio support
Sennheiser HD 660s2 supports spatial audio, the average headphone does not. 30.7% of headphones support spatial audio.
10 Hz lower bass extension
Sennheiser HD 660s2 has a lower lowest frequency than the average headphone (8 Hz vs 18 Hz). The average headphones reach a lowest frequency of 18 Hz.
21,500 Hz higher treble extension
Sennheiser HD 660s2 has a higher highest frequency than the average headphone (41,500 Hz vs 20,000 Hz). The average headphones reach a highest frequency of 20,000 Hz.
0.26 % lower distortion
Sennheiser HD 660s2 has a lower total harmonic distortion than the average headphone (0 % vs 0.3 %). The average headphones have total harmonic distortion of 0.3 %.

Why is Sennheiser HD 660s2 worse than the average headphone?

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19.3% higher weight
Sennheiser HD 660s2 is heavier than the average headphone (260 g vs 218 g). The average pair of headphones weighs 218 g.
1.7 higher clamp force
Sennheiser HD 660s2 has a higher clamp force than the average headphone (6 vs 4.3). The average headphones have a clamp force of 4.3.
8 mm tighter earcup width
Sennheiser HD 660s2 has tighter earcup width than the average headphone (35 mm vs 43 mm). The average headphones offer an inner earcup width of 43 mm.
No passive noise reduction
Sennheiser HD 660s2 does not offer passive noise reduction, while the average headphone does. 82.7% of headphones have passive noise reduction.
2 mm smaller driver size
Sennheiser HD 660s2 has smaller driver size than the average headphone (38 mm vs 40 mm). The average headphones use a driver size of 40 mm.
2 dB/mW lower sensitivity
Sennheiser HD 660s2 has a lower sensitivity than the average headphone (100 dB/mW vs 102 dB/mW). The average headphones have sensitivity of 102 dB/mW.
No neodymium magnet
Sennheiser HD 660s2 does not use neodymium magnets, the average headphone does. 77.4% of headphones use neodymium magnets.
Not headset-ready
Sennheiser HD 660s2 is not headset-ready, while the average headphone is. 84.7% of headphones can be used as headsets.
1 fewer microphones
Sennheiser HD 660s2 has fewer microphones than the average headphone (0 vs 1). The average headphones have 1 microphones.
No voice assistant support
Sennheiser HD 660s2 does not support voice assistants, the average headphone does. 60.8% of headphones support voice assistants.
No passive noise reduction
Sennheiser HD 660s2 does not offer passive noise reduction, while the average headphone does. 82.7% of headphones have passive noise reduction.
What it is: Shows whether the headphones reduce outside noise through physical sealing, fit, and materials rather than active electronics.
When it matters: When you want better isolation from fit and seal alone, even with ANC turned off or not available.
Importance: MEDIUM
Sennheiser HD 660s2 does not offer passive noise reduction, while the average headphone does. 82.7% of headphones have passive noise reduction.
No voice assistant support
Sennheiser HD 660s2 does not support voice assistants, the average headphone does. 60.8% of headphones support voice assistants.
What it is: Compatible with voice assistants like Siri, Alexa, or Google Assistant
When it matters: When hands-free control is part of your daily routine.
Importance: LOW
Sennheiser HD 660s2 does not support voice assistants, the average headphone does. 60.8% of headphones support voice assistants.
2 mm smaller driver size
Sennheiser HD 660s2 has smaller driver size than the average headphone (38 mm vs 40 mm). The average headphones use a driver size of 40 mm.
What it is: Diameter of the speaker driver unit
When it matters: When you want extra hardware context behind how the headphones may handle bass weight, scale, or overall presentation.
Importance: MEDIUM
Sennheiser HD 660s2 has smaller driver size than the average headphone (38 mm vs 40 mm). The average headphones use a driver size of 40 mm.38 mm vs 40 mm
Not headset-ready
Sennheiser HD 660s2 is not headset-ready, while the average headphone is. 84.7% of headphones can be used as headsets.
What it is: Shows whether the headphones can handle voice chat and calls in addition to normal audio playback.
When it matters: When one pair needs to cover music, calls, meetings, and gaming chat.
Importance: MEDIUM
Sennheiser HD 660s2 is not headset-ready, while the average headphone is. 84.7% of headphones can be used as headsets.
19.3% higher weight
Sennheiser HD 660s2 is heavier than the average headphone (260 g vs 218 g). The average pair of headphones weighs 218 g.
What it is: Total weight of the headphones
When it matters: When long listening sessions make wearing comfort more important.
Importance: MEDIUM
Good value: <150 g
Sennheiser HD 660s2 is heavier than the average headphone (260 g vs 218 g). The average pair of headphones weighs 218 g.260 g vs 218 g
1.7 higher clamp force
Sennheiser HD 660s2 has a higher clamp force than the average headphone (6 vs 4.3). The average headphones have a clamp force of 4.3.
What it is: Amount of clamping pressure applied to the head
When it matters: When comfort and fit security matter during long sessions.
Importance: MEDIUM
Sennheiser HD 660s2 has a higher clamp force than the average headphone (6 vs 4.3). The average headphones have a clamp force of 4.3.6 vs 4.3
8 mm tighter earcup width
Sennheiser HD 660s2 has tighter earcup width than the average headphone (35 mm vs 43 mm). The average headphones offer an inner earcup width of 43 mm.
What it is: Internal width of the earcup cavity
When it matters: When earcup fit affects comfort and pressure around your ears.
Importance: MEDIUM
Sennheiser HD 660s2 has tighter earcup width than the average headphone (35 mm vs 43 mm). The average headphones offer an inner earcup width of 43 mm.35 mm vs 43 mm
4.33x more expensive
Sennheiser HD 660s2 is more expensive than the average headphone (£390 vs £90).
Sennheiser HD 660s2 is more expensive than the average headphone (£390 vs £90).£390 vs £90

Calls & Controls

Graphic comparison of Sennheiser HD 660s2 and

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Third-party reviews

United Kingdom

United States

(Reviews last updated: June 2026)

What customers like about Sennheiser HD 660s2?

Significantly improved sub-bass extension and low-end punch compared to previous models
Natural and warm midrange performance that excels with vocals and acoustic instruments
Non-fatiguing, smooth treble that remains detailed without being sharp or piercing
Lightweight design with soft velour earpads suitable for long listening sessions
Durable, modular build quality with a classic aesthetic and high-quality cables
Excellent imaging and spatial accuracy, which also makes them effective for gaming

What customers dislike about Sennheiser HD 660s2?

High MSRP that many users find difficult to justify compared to older HD 600-series models
Strong initial clamping force that can be uncomfortable before a 'break-in' period
Open-back design results in high sound leakage and zero noise isolation
Requires a dedicated headphone amplifier (300-ohm impedance) to achieve optimal performance
Average soundstage width that can feel 'intimate' or slightly narrow for an open-back
Packaging is simpler than previous iterations, lacking a premium hard storage case

Expert reviews

senses.se

24/09/2024

Review: Sennheiser HD 660S2 (open back) - Senses.se Proactive Follow-up Would you like me to find technical measurements (like frequency response grap...

The Senses review of the Sennheiser HD 660S2 open-back, over-ear headphones positions the model as a premium product with mixed results when compared to its legendary predecessors. Weighing 260 grams, the headphones are noted for their high-quality construction and a comfortable fit, though they exhibit a somewhat firm clamping force out of the box. A prominent highlight is the...Read more

techradar.com

24/03/2023

Sennheiser HD-660S2 review: easy on the ears at home

The Sennheiser HD-660S2 over-ear headphones are wired, open-back cans designed primarily for stationary listening, sound mixing, and studio tracking. They offer a characteristically neutral and relaxed audio signature that effectively expands audio across a wide frequency range (8Hz to 41,500Hz). A key highlight is their high impedance rating of 300 Ohms, which works alongside a...Read more

head-fi.org

07/02/2023

Sennheiser HD 660S2 - Reviews - Head-Fi Are you looking for specific technical measurements (like frequency response graphs) or expert opinions on how...

The Sennheiser HD 660S2 is a warm, natural-sounding open-back headphone featuring a redesigned 38mm transducer that delivers 5-6dB more presence in the sub-bass region compared to previous models. These headphones are praised for their exceptional technicalities, clear micro-detailing, and fatigue-free treble, providing a significant upgrade for bass-conscious listeners without...Read more

rtings.com

08/03/2023

Sennheiser HD 660S2 Headphones Review - RTINGS.com

The RTINGS review of the Sennheiser HD 660S2 identifies them as open-back, over-ear headphones designed for neutral, critical listening, featuring a comfortable, lightweight design and improved, warmer bass compared to their predecessors. Key advantages include robust build quality, comfortable velour pads, and enhanced low-end thump for a more engaging sound profile. However, the...Read more

headphonesty.com

06/11/2023

Sennheiser HD 660S2 Review – Great Expectations

The Headphonesty review characterizes the Sennheiser HD 660S2 as an exceptionally polished, open-back headphone, offering a natural, warm sound with enhanced, deep sub-bass extension. Key strengths include lightweight construction, improved sub-bass, and clear, fatigue-free treble. Conversely, the review notes a high MSRP that makes the minor upgrades over earlier models difficult...Read more

headfonics.com

23/09/2023

Sennheiser HD 660S2 Review

The Headfonics review of the Sennheiser HD 660S2 highlights significant improvements in sub-bass extension, weight, and overall frequency extension compared to the original model, while maintaining a natural, organic tone suitable for OTL tube amplifiers. Key strengths include improved technical performance, a more intimate soundstage with better dynamics, and a practical 300Ω...Read more

soundguys.com

30/06/2023

Sennheiser HD 660S2Go to product viewer dialogue for this item. review - SoundGuys

The SoundGuys review of the Sennheiser HD 660S2 highlights the open-back headphones' superior, natural sound, praising the improved sub-bass extension and comfortable, durable build for critical listening. However, the 300-ohm, open-back design requires a dedicated amplifier and offers no isolation, resulting in significant sound leakage. While audio imaging is precise, the...Read more

whathifi.com

28/05/2023

Sennheiser HD 660S2 review - What Hi-Fi?

The Sennheiser HD 660S2 premium open-backed wired headphones offer a relaxed, smooth, and highly refined sound signature that makes them exceptionally comfortable for long, uncomplicated listening sessions. Their biggest strength lies in a breathtaking midrange, delivering captivated and silky-smooth vocals that shine on acoustic and vocal-heavy tracks. Architecturally, they are...Read more

headfonia.com

08/05/2023

Sennheiser HD 660S2 Review

The Headfonia review characterizes the Sennheiser HD 660S2Go as a refined 300-ohm evolution of the 600-series, featuring a warm, natural sound profile with significantly improved sub-bass performance. It offers excellent technicalities, including precise imaging and a "holographic" presentation, though it maintains an intimate soundstage. HeadfoniaKey advantages include musical,...Read more

expertreviews.co.uk

15/03/2023

Sennheiser HD 660S2 review: Wired for sound

The Sennheiser HD 660S2 are wired, open-backed over-ear headphones designed for high-performance domestic listening. They excel at delivering a punchy, expansive, and highly detailed audio experience. Their open-backed design creates a wide-open, coherently defined soundstage where individual instruments and vocalists have plenty of room to express themselves clearly. The...Read more

likehifi.de

14/03/2023

Review: Sennheiser HD 660S2 - Open-Back Over-Ear HiFi Headphones

The Sennheiser HD 660S2 is an open-back, over-ear audiophile headphone reviewed by Artur Evers for Likehifi.de, earning an exceptional overall score of 96%. Priced at €599 (RRP), this model is manufactured in Tullamore, Ireland, and features a newly engineered, ultra-lightweight aluminum voice coil housed inside a 38 mm dynamic driver. The review strongly highlights several acoustic...Read more

modernhifi.de

23/04/2024

Sennheiser HD 660S2 Review: Open-Back Headphones

The Sennheiser HD 660S2 is an open-back, over-ear headphone tailored for home-use audiophiles, retailing at an MSRP of 599 Euro with street prices around 430 Euro. Weighing 313 grams, the headphone features distinctive oval earcups with metal grilles and soft velour earpads that ensure high wearing comfort during long listening sessions. It comes equipped with a solid accessory...Read more

hifitest.de

11/07/2023

Sennheiser HD660S2 - Hi-Fi Headphones Review - hifitest.de

The Sennheiser HD660S2 is described as the "Most Valuable Player" of the brand’s legendary HD series, successfully returning to a 300-ohm impedance after its predecessor's brief foray into lower impedance levels. The review highlights a significant technical overhaul, including a more powerful magnet system and a lighter aluminium voice coil, which results in a doubling of sound...Read more

kopfbox.de

18/02/2023

Sennheiser HD660S2 in the Kopfbox Review", "Sennheiser HD660S2 Kopfbox Review

The Sennheiser HD660S2 builds upon the legacy of its predecessor, the HD660S, by introducing a newly developed driver with a 300-ohm impedance, matching the iconic HD600 and HD650 models. While the timeless, robust plastic design and comfortable microfaser-earpad fit remain nearly identical, under the hood changes significantly enhance the sound. The reviewer, a drummer, notes that...Read more

lowbeats.de

09/11/2023

Sennheiser HD 660S2: The bass-optimized over-ear classic reviewed by kopfhoerer.de

The LowBeats review identifies the Sennheiser HD 660S2 as a refined, open-back classic delivering significantly improved low-frequency performance through a redesigned transducer, offering deep, dry, and detailed bass. Key advantages include exceptional comfort, a transparent soundstage, and superior sub-bass rendering compared to its predecessor. Conversely, the review notes that...Read more

bonedo.de

13/06/2023

Sennheiser HD 660S2 Review - Bonedo

The Sennheiser HD 660S2 is an open-back, over-ear headphone built in Ireland that modernizes the classic HD 600 design with updated technical specifications. Shifting away from recent trends toward low-impedance gear, this model increases its impedance to 300 Ohms (up from its predecessor's 150 Ohms) and expands its frequency response to a wide 8 to 41,500 Hz. Despite the higher...Read more

kopfhoerer.de

21/02/2023

Sennheiser HD 660S2 review on kopfhoerer.de", "Sennheiser HD 660S2 tested by kopfhoerer.de

The Sennheiser HD 660S2 open-back, over-ear headphones are highlighted as a premium blend of high-fidelity enjoyment and professional audio tools, acting as a direct evolution of the previous HD 660S models. A key structural upgrade includes an overhauled aluminum voice coil with an increased impedance of 300 ohms (up from 150 ohms) designed to optimize impulse response. The audio...Read more

hifi.de

08/02/2023

Sennheiser HD 660S2 Review: Open-Back Headphones Learn Bass", "Sennheiser HD 660S2 Reviewed: Open-Back Headphones Finally Get Bass

The Sennheiser HD 660S2 is an open-back, over-ear audiophile headphone handcrafted in Tullamore, Ireland, designed specifically for home listening. Retailing at 599 Euro, this model introduces a 38-millimeter dynamic transducer and a 300-ohm impedance, which is twice that of its predecessor and demands a dedicated headphone amplifier to reach adequate volume. The review highlights a...Read more

digitec.ch

10/08/2023

Sennheiser HD 660S2: sounds great - Digitec

The Digitec review of the Sennheiser HD 660S2 highlights a balanced, warm, and precise sound ideal for indoor listening, featuring comfortable fabric ear pads, a 260-gram weight, and high-quality 4.4 mm and 6.3 mm cables. While praised for comfort, potential buyers should note the initial high clamping force of the headband. However, the review indicates that the promised, enhanced...Read more

galaxus.fr

10/08/2023

Sennheiser HD 660S2: sounds great", "Sennheiser HD 660S2: it sounds good

The Galaxus review of the Sennheiser HD 660S2 highlights a balanced, warm, and precise sound signature, with comfortable, lightweight construction and a high-quality accessory package including 4.4 mm balanced cables. While praised for smooth, non-fatiguing treble, the headphones are designed for quiet environments due to their open-back nature, allowing sound leakage. Conversely,...Read more

homecinema-fr.com

05/05/2023

Sennheiser HD 660S2 Review", "Sennheiser HD 660S2 Test

The HCFR News & Forum collaborative review presents the Sennheiser HD 660S2 as a meaningful, high-performance evolution of the affordable audiophile reference line. As the direct successor to the original HD 660S, the S2 version preserves the signature structural DNA of the 600-series while engineering significant physical and technical enhancements. The reviewers—Jeff_jacko,...Read more

on-mag.fr

06/03/2023

Sennheiser HD 660 S2 Hi-Fi Headphones Review - Has the Brand Finally Found the Ideal Sound Formula?

The Sennheiser HD 660 S2 is an open-back hi-fi headphone that modernizes the classic design of the HD 600 series with enhanced sonic maturity, earning a 4.5/5 rating at a €600 price point. On the positive side, the headphones deliver a highly engaging and well-balanced sound profile, blending the clear, lively nature of the HD 660 S with the beautiful midrange reproduction of the HD...Read more

fr.audiofanzine.com

04/10/2023

Sennheiser HD660 S2 Review: Bassline Junkie

The Sennheiser HD660 S2 is an open-back, over-ear headphone that aims to deliver deeper bass than its predecessor, but the overall results are mixed. On the positive side, the headphones feature an exceptionally clear and linear midrange, accurate treble, and a very good stereo image. They are also highly durable, easy to take apart for repairs, lightweight at 260 grams, and come...Read more

zococity.es

N/A

Sennheiser HD660 S2 - Open-back headphones - Zococity.es Audio46 +8

The Sennheiser HD660 S2 is an open-back, over-ear audiophile headphone priced at €435.00 (discounted from €599.00) that enhances its predecessor's design with doubled sound pressure in the lowest octaves and an ultra-lightweight 300-ohm aluminum voice coil. Reviewers highly praise its natural, warm, and relaxed sound signature, which features intimate mid-ranges, smooth treble, and...Read more

digitec.ch

10/08/2023

Sennheiser HD 660S2: music to my ears?

The Sennheiser HD 660S2 is a "no-frills" open-back headphone characterized by an exceptionally warm, precise sound profile and a noticeable increase in bass compared to its predecessor. Weighing only 260 grams with comfortable velour padding, these headphones are well-suited for extended, quiet indoor listening sessions. However, the 300-ohm impedance requires a dedicated amplifier,...Read more

tnt-audio.com

15/10/2024

Sennheiser HD 620S and HD 660S2

The Sennheiser HD 620S ($299) is a closed-back model designed to deliver a wider, more open soundstage than traditional closed designs, though the reviewer felt its presentation was overly emphasized and lacked a natural acoustic feel. On the positive side, it offers exceptionally solid bass and a flatter low-frequency response than the classic HD 600. However, its distinct cons...Read more

galaxus.it

10/08/2023

Sennheiser HD 660S2: music to my ears?

The Sennheiser HD 660S2Go is a "no-frills" open-back headphone offering a warm, precise sound with punchy, improved bass dynamics and comfortable, lightweight 260-gram construction. It features practical, detachable cables, including a 4.4 mm balanced option, making it a strong choice for stationary high-fidelity listening. Conversely, the 300-ohm impedance makes it unsuitable for...Read more

smartworld.it

05/01/2026

Sennheiser HD 660S2 review: high-fidelity studio headphones (and more)

The Sennheiser HD 660S2 is an open-back, over-ear audiophile headphone designed for both audio professionals and music enthusiasts looking for top-tier audio quality. Priced at a list price of €599.99 (frequently discounted below €400), it features 38mm dynamic drivers and an exceptionally high impedance of 300 ohms, meaning it requires a dedicated DAC, mixer, or sound card to...Read more

hardware.info

27/12/2023

Sennheiser HD660 S2: Luxurious headphones with exceptional smoothness

The Hardware Info review highlights the Sennheiser HD660 S2 as a premium, open-back headphone engineered specifically for dedicated music listening rather than casual PC communication or gaming. Priced at approximately €495, this model stays true to the signature German engineering of the brand by prioritizing a natural, precise, and highly exact sound profile over the artificially...Read more

fwd.nl

25/02/2023

Review: Sennheiser HD 660S2 - Modern interpretation of a head-fi classic

The Sennheiser HD 660S2 is an open-back, high-end headphone priced at €599 that modernizes a classic head-fi lineup by introducing a more bass-oriented sound signature. It retains the traditional, functional German studio aesthetic of its predecessors with large oval earcups, a lightweight 260-gram body, and improved, user-friendly clamping force that ensures excellent long-term...Read more

gadgetgear.nl

04/03/2023

Sennheiser HD 660S2: Truly dives deeper into your music", "Sennheiser HD 660S2: Dives genuinely deeper into your music

The Sennheiser HD 660S2, reviewed by GadgetGear, is a five-star, open-back headphone characterized by an intensely pure, warm, and detailed sound profile that improves upon the bass limitations of the HD 600 line. These comfortable, high-fidelity headphones are designed for long listening sessions, offering exceptional sound quality. However, the design features inherent...Read more

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