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Sennheiser HD 660S2 Open-Back Wired Over-Ear Headphones (Open Box)

Sale Sale
Original price $ 499.95
Original price $ 499.95 - Original price $ 499.95
Original price $ 499.95
Current price $ 469.77
$ 469.77 - $ 469.77
Current price $ 469.77

Sennheiser HD 660S2 Open-Back Wired Over-Ear Headphones (Open Box)

What are Open Box Products? OPEN BOX items are tested and certified to look and work like New. These products may have been returned to us by a customer or were on display in our retail stores. In most cases these items are in "Like - NEW Condition" and are fully functional. These products ship with all relevant accessories and will arrive in the original box.

• Great way to save on the latest technology!
• Availability is limited to stock on hand.

  • All original accessories included, unless indicated.
  • Open Box items are sold on a first-come first-served basis.
  • For more details please do not hesitate to give us a call at 1.888.707.3976.
  • Parts and Labor Manufacturer Warranty.
  • 30-day money-back guarantee.


From thundering timpani, to the melodic sound of a guitar, the impressive singing voice of your favorite artist, or the beat of electronic dance music, nothing creates drama like powerful bass. Ideal for music lovers, the non-fatiguing, high-end HD 660S2 now delivers even more impact and emotion. Our engineers optimized the HD 660S's surround, transducer airflow, and coil to double the sound pressure at the lowest octaves. You can feel the lowest note on the piano (27.5 Hz) or the kick of the bass drum (45-60 Hz) as if you were there at the recording studio, allowing you to pick out individual instruments and discover new sonic details. The relaxed sound and open-black design make it an extremely comfortable headphone that is also suitable for long listening sessions. The headphone's warm, relaxed sound is reflected in its timeless design and elegant bronze accents. With warm tuning, smooth treble and strong bass, the standard-setter for extended listening is now also the standard for extended bass.

Product Highlights:

  • Over-the-ear design
  • Open-back, metal mesh covered ear cups for proper ventilation and transparent sound
  • Part of Sennheiser's legendary HD600 series headphones
    • Streamlined design with timeless matte black finish and gold accents
    • Designed in Germany, made at Sennheiser's "audiophile center of excellence" facility in Ireland
  • We recommend a separate headphone amplifier for proper power and the best possible sound
Driver Design:
  • 38mm dynamic drivers deliver a smooth, articulate sound with extended bass response
  • Intimate, layered soundstage with precise imaging
  • Vented magnet design for tightly controlled diaphragm movement
  • Soft diaphragm lined with stainless steel mesh for even airflow
  • Ultralight aluminum voice coils ensure precise impulse control and fast transient response
General Info and Specs:
  • Snug, cushioned fit
    • Generous velour ear pads and soft headband padding
  • Two detachable 6-foot oxygen-free copper cables:
  • Balanced cable with 4.4mm headphone plug
  • Unbalanced cable with 1/4" headphone plug
  • Includes 3.5mm mini plug adapter
  • Frequency response: 8-41,500 Hz
  • Sensitivity: 104 dB
  • Impedance: 300 ohms
  • Weight: 9.2 oz. (without cable)
  • Warranty: 2 years
  • Our 30-day money back guarantee
  • MFR # 700240

What's In The Box:

  • Over-ear headphones
  • 69" Unbalanced audio cable with two 2-pin connectors on one end and 1/4" plug on other end (installed)
  • 69" Balanced audio cable with two 2-pin connectors on one end and 4.4mm connector on other end
  • 9" Audio adapter cable (female 1/4" jack on one end and male 3.5mm plug on other end)
  • Cloth storage bag with drawstring closure
  • User Information
  • Quality Certificate