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Sennheiser

Sennheiser HD 660S2

Name: Sennheiser HD 660S2
Brand: Sennheiser
SKU: B0BRT1ZN7Q
Price: 433.28 USD

A new model sits atop the HD 600 line.

Current price · Amazon US

$433.28

Check Price on Amazon

Price last checked 1d ago

Noise Isolation / ANC

0.7/ 10

0.7

0.010.0

A 0.7 puts its noise isolation / ANC in the bottom 10% of over-ear headphones we've measured.

Measured on 86 of the 240 we've cataloged.

Key specs

Connection Type

Wired 3.5mmMost common

Wired-3.5mm48%Bluetooth44%Wired-usb-c7%Others1%

Wired-3.5mm is the most common — on 48% of the 215 over-ear headphones we've cataloged (of 240).

Weight

260 gBelow average

240 g

132 g420 g

below average for over-ear headphones — based on 195 of 240 we've cataloged.

Connectivity

Connection Type: Wired 3.5mm

Design

Weight: 260 g
Foldable: No
Headband Type: Adjustable over-head

Build

Material Chassis Primary: Plastic
Material Ear Cups: Velour
Material Headband: Spring steel

Sound

Acoustic Design: Open-back
Driver Count: 1
Driver Size: 38 mm
Driver Type: Dynamic driver
Frequency Response: 8-41.5 Hz
Frequency Response High Hz: 42 Hz
Frequency Response Low Hz: 8 Hz
Frequency Response Signature: Flat
Impedance: 300 Ω
Sensitivity: 104 dB/mW

Battery

Battery: No

Microphone

Microphone: No

SoundGuys review

Read the full review ›

SOUNDGUYS rating

6.3/ 10

Worth a look

Reviewed byChristian ThomasEditor-at-largeReviewed June 2023

Isolation0.7

Comfort & fit9.7

Connectivity6.5

Design9.0

Portability4.5

Features7.0

The verdict

The Sennheiser HD 660S2 is slightly bassier than its predecessor, but this isn't for bass-heads, and also not for those who need significant treble emphasis. It's not a good or bad thing, it's just a preference issue—but this fact should inform your buying decisions.

✓What we like

✓Good sound

✓Easy maintenance

✓Comfort

✓Connectivity

✕What could be better

✕Sound not for everyone

✕Price

Read the full SoundGuys review →

Lab data

How we test ›

Objective measurements from the SoundGuys test lab — overlay other models to see how this one compares.

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0 of 4 overlay slots used

Sennheiser HD 660S2SoundGuys Headphone Preference Curve

Measured frequency response (dB) against the SoundGuys house target — the dashed curve. The closer the measured line tracks the target, the more neutral the tuning; peaks ride above the target, dips fall below it.

Frequency response — measurement data

Sennheiser HD 660S2: frequency response, as measured in the SoundGuys lab. Frequency in hertz.
Frequency (Hz)	Response (dB)
20	-8.9
25	-6.9
32	-5.1
40	-3.7
50	-2.7
63	-2.2
80	-1.9
100	-1.2
125	-0.9
160	-1.0
200	-1.0
250	-1.0
315	-1.1
400	-1.2
500	-1.3
630	-1.0
800	-0.4
1000	0.0
1250	1.1
1600	1.9
2000	2.5
2500	4.6
3150	6.7
4000	4.4
5000	2.7
6300	6.4
8000	6.2
10000	3.4
12500	-0.8
16000	-5.1
20000	-19.4

Sennheiser HD 660S2

Passive isolation (dB) with ANC off — how much ambient noise the fit blocks on its own. Higher on the chart means more attenuation.

Passive isolation — measurement data

Sennheiser HD 660S2: passive isolation, as measured in the SoundGuys lab. Frequency in hertz.
Frequency (Hz)	Attenuation (dB)
21	0.4
26	0.3
33	0.1
41	-0.1
52	-0.0
65	-0.1
82	-0.2
103	0.1
130	0.0
163	0.1
205	-0.1
259	-0.0
325	-0.1
410	-0.3
516	-0.1
613	-0.2
772	-0.7
972	-1.2
1220	-1.2
1540	0.1
1940	3.3
2440	8.6
3070	7.2
3870	8.7
4870	11.5
6130	17.8
7720	16.7
9720	15.3
12200	2.3
15400	10.4
19400	11.1