New Release Sennheiser HD 660 S Open-Back Headphones

Sennheiser HD 660 S Headphones - New Release

Today audiophiles are literally falling out of their chairs with the announcement of a brand new headphone dubbed the Sennheiser HD 660 S. This audiophile grade headphone is a step up from the insanely popular HD 600 and HD 650 and may just be the “Holy Grail” of open-back reference headphones. Priced at just under $500 the HD 660 S is a headphone model that’s been a long time coming. Let’s take a look at the features and specs.


The Sennheiser HD 660 S open-back headphone is said to have an improved design over the HD 650. Here’s what we know so far.

  • Reference class open back dynamic wired headphones
  • New improved transducer design for very low harmonic distortion
  • Low impedance (150 Ohms) for flexibility with Hi-Res players
  • Detachable cable made with OFC copper, with very low handling noise and para-aramid reinforced
  • 6.35mm stereo plug / 4.4mm Pentaconn balanced stereo plug / 6.35mm to 3.5mm adapter
  • Frequency response 10 Hz to 41,000 Hz
  • Better sound including “crisp bass”
  • Stainless steel fabric adds improved control of diaphragm
  • Light aluminum voice coils
  • Storage box (included)
  • 2-year warranty


The design of the HD 660 S is very similar to the HD 650 but has an all new matte black and anthracite look. You’ll still get the iconic headband and earpads designed for maximum comfort and hours of listening. Another familiar aspect to the new HD 660 S is the removable cable with 6.35mm plug which gives you options if you wish to upgrade or replace your wires at some point. It also comes with another removable cable with a 4.4mm Pentaconn stereo plug. The transducers are said to be hand picked and kept within tolerances of +/-1dB.

HD 660 S Headphone Cables
Sennheiser HD 660 S Headphone Cables


When Will It Be Available?

The Sennheiser HD 660 S Audiophile Headphones will be available for purchase beginning November 16. Hungry headphone seekers can place their orders on the release date at Audio46 Headphone Store in NYC. There’s no doubt it will be a hot item and may even be hard to find as the Christmas season approaches.

Buy Sennheiser HD 660 S Open Back Headphones

Read our Sennheiser HD 660 S Headphone Review


Impedance: 150 Ω
Connector: Stereo jack plug, gold-plated 6.35 mm, unbalanced, 3-pin 4.4 mm, balanced, 5-pin
Frequency response: 10 – 41,000 Hz (-10 dB)
Sound pressure level (SPL): 104 dB at 1V 1kHz
Ear coupling: Over-ear (circumaural)
THD + N, total harmonic distortion and noise: < 0,04% (1 kHz, 100 dB)
Transducer principle (headphones): Dynamic, open
Weight w/o cable: Approx. 260 g (without cable)

Sennheiser HD 660 S Audiophile Headphones - MajorHifi
Sennheiser HD 660 S Audiophile Headphones

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An audio engineer living in Brooklyn, NY, Steven spends his spare time enjoying the sounds of ethereal indie rock and creating electronic music.