About the Sennheiser HD 660 S
A classic revisited
A classic revisited
Many of us here at Crutchfield credit Sennheiser's legendary "HD 600" series as our gateway into the world of truly high-end personal audio. These HD 660 S headphones keep the spirit of their stellar predecessors alive (and we recently ranked them one of our "Top 5 most comfortable headphones"). They feature a tweaked design and completely revamped driver system.
The HD 660 S headphones features velvet-soft ear pads and hold into place without squeezing too tightly.
The result is a smooth, timeless look and — more importantly — even greater musical detail. When paired with a high-performance headphone amp, you get great clarity with pinpoint imaging.
Our most comfortable audiophile headphones
In 2019, we did a deep dive on headphone comfort and asked 20 employees to test and score over 50 popular headphones. The HD 660 S was named our most comfortable set of audiophile headphones. This class of headphones is primarily geared toward sound, so they feature large, sophisticated drivers.
But while the open-back HD 660 S features larger earcups than most “general purpose” headphones, the weight is distributed nicely. And our testers said that they felt lighter than other large audiophile headphones. The velvety cloth ear pads press gently on the side of your head, and give your ears plenty of room to breathe.
Plus they stay in place really well. And we learned that security and stability were the most important comfort and fit traits to our testers.
Several ways to connect
These headphones includes two cables, one with 4.4mm balanced headphone plug. This is quickly becoming the new industry standard connection for balanced headphone operation, and I've seen more and more companies adopt it.
I've found that the compact, yet powerful iFi ZEN DAC pairs up really nicely with the HD 660 S 'phones. It's a natural combo. I heard the classic HD 600-series immediate, forward sound signature — but there was an extra level of depth I didn't notice when connecting directly to my phone.
(For more traditional headphone connections, Sennheiser includes another cable with an unbalanced 1/4" plug and a 3.5mm miniplug adapter.)
- over-the-ear design
- open-back, metal mesh covered ear cups for spacious and transparent sound
- latest model in Sennheiser's legendary HD600 series headphones
- streamlined design with timeless matte black finish
- we recommend a separate headphone amplifier for proper power and the best possible sound
- large dynamic drivers angled to create a more natural listening experience and a wider soundstage
- cutting edge transducer design for tightly controlled diaphragm movement
- diaphragm lined with stainless steel mesh for even airflow
- lightweight aluminum voice coils ensure accuracy and fast transient response
General Info and Specs:
- snug, cushioned fit
- generous velour ear pads and soft headband padding
- specially tuned 9-foot oxygen-free copper cable with balanced 4.4mm headphone plug
- connects to the Sennheiser HDV 820 headphone amp
- 9-foot oxygen-free cable with unbalanced 1/4" headphone plug
- includes 3.5mm mini plug adapter
- storage box
- frequency response: 10-41,000 Hz (-10 dB)
- sensitivity: 98 dB
- impedance: 150 ohms
- weight: 9.2 oz. (without cable)
- warranty: 2 years
- Our 60-day money-back guarantee
- MFR # 508826
- Feels lighter than most
- Soft padding (earcups)
- Good for focused listening
What's in the box:
- Over-ear headphones with 10' audio cable (1/4" plug)
- 9" Adapter (1/4"-to-3.5mm)
- 10' Balanced audio cable (4.4mm Pentaconn)
- Hinged storage box
- Instruction manual
More details on the Sennheiser HD 660 S
Features & specs
|Earcup Width x Height||3.252" x 4.288"|
|Mic For Taking Calls||No|
|Voice Assistant Access|
|Frequency Response||10-41k Hz|
|Cord Length||120" + 120|
|Parts Warranty||2 Years|
|Labor Warranty||2 Years|
Overview: The Sennheiser HD 660 S high-end headphones feature an open design to give you an exceptionally natural, spatial, and accurate sound. Unlike closed, noise-isolating earcups, the HD 660 S's earcups have a specialty steel mesh, molded to the natural shape of the acoustic chamber, to provide an open environment. The HD 660 S features new, lower-impedance drivers with extremely light aluminum voice coils. The transducers are matched within +/- 1dB tolerances for consistent sound. The headphones come with two 10' cables, one with the new 4.4mm balanced connector, and a hinged storage box.
Angled Transducers: The HD 660 S has angled transducers to resemble the perfect positioning of a pair of reference monitors to put you in the center of the sweet spot. The ear cups are elliptical to follow the shape of the outer ear, with plush, velour-covered padded ear cushions for hours of listening comfort.
Headphone Cables: The HD 660 S comes with two interchangeable, 10-foot cables. One cable has a full-sized 1/4" plug. A 1/4"-to-3.5mm adapter is included for listening to portable devices. The other cable (also 10') is terminated with a new 4.4mm Pentaconn balanced connection that can be used with some high-end digital audio players (such as the Sony TA-ZH1ES) and headphone amplifiers (including the Sennheiser HDV 820). Both cables are constructed with OFC copper (oxygen-free copper) with its high conductivity for best signal transfer. The cable's outer jacket is coated to greatly reduce handling noise.
Storage Box: The HD 660 S has a sturdy, hinged box with cut-out foam padding for storage of your headphones and attached cable.
- Frequency Response: 10-41kHz
- Nominal Impedance: 150Ω
- Sound Pressure Level (1 kHz/1V): 104dB
- THD + N (1kHz/100dB): <0.04%
- Maximum Input Power: 500mW
- Weight: 9.2 ounces (w/o cable), 12.5 ounces (w/cable)