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Sennheiser

Sennheiser HD 660S

Name: Sennheiser HD 660S
Brand: Sennheiser
SKU: B076HP574T
Price: 443.75 USD

From the same stable as the classic HD 600, what does that extra 60S get you?

Current price · Amazon US

$443.75

Check Price on Amazon

Price last checked 21h ago

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

260 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
Ear Pad Inner Dimensions: 70×40 mm
Foldable: No

Sound

Acoustic Design: Open-back
Driver Size: 45 mm
Driver Type: Dynamic driver
Frequency Response: 10-41000 Hz
Frequency Response High Hz: 41000 Hz
Frequency Response Low Hz: 9 Hz
Impedance: 150 Ω
Sensitivity: 104 dB/mW

SoundGuys review

Read the full review ›

SOUNDGUYS rating

6.1/ 10

Worth a look

Reviewed byAJ WykesReviewed June 2023

Comfort & fit9.0

Connectivity6.5

Design8.0

Portability2.0

Features6.0

Value5.0

The verdict

While it doesn't quite have the analytical sound signature of the highly regarded "reference" HD 600, it's close, and the Sennheiser HD 660S is well constructed, very comfortable, and gives a pleasant listen for hours at a time.

✓What we like

✓Sound quality

✓Comfort

✓Replaceable cables

✓Connections provided for standard and balanced amps

✕What could be better

✕Not a significant step up from less expensive Sennheiser models

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 660SSoundGuys 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 660S: 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 660S

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 660S: 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