Product Details

The HD 660 S lets you enjoy sophisticated audiophile sound in even more listening situations.

Thanks to its lower impedance, it delivers reference-class sound also when connected to hi-res mobile players, thus offering much greater versatility. The HD 660 S is an elegantly designed piece of high-quality engineering that indulges the demanding listener with aural precision and great wearing comfort.


  • Crisp bass, excellent mid-frequency response, natural treble
  • Supplied with two connection cables: One with a 6.35 millimeter stereo plug, the other a 4.4 mm Pentaconn balanced stereo plug
  • Also included is a 6.35 mm to 3.5 millimeter adaptor. Connectivity Technology: Wired 6.35 millimeter / 4.4 millimeter Pentaconn


  • Impedance
  • 150 om
  • Connector
  • 6.35 mm / 4.4 mm Pentaconn
  • Frequency response
  • 9 - 41,500 Hz (-10 dB)
  • Sound pressure level (SPL)
  • 108 dB at 1V 1kHz
  • Ear coupling
  • Over-ear (circumaural)
  • THD + N, total harmonic distortion and noise
  • less than 0,04% (1 kHz, 100 dB)
  • Transducer principle (headphones)
  • Dynamic, open
  • Weight w/o cable
  • Approx. 260 g (without cable)
Model number:
  • 508231

Delivery and Returns

Delivery information:
This item may be delivered separately from other items purchased
Returns Policy:

Many of our products come with a guarantee or warranty from the manufacturer. If you are unhappy with the condition or performance of your new items, please get in touch with the Rewards Store Customer Service team via the Contact Us page.

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Ratings and Reviews


HD 660 S - HiRes Audiophile Open Back Headphone

2,000PTS + $787.51
Standard delivery
1,200 PTS or $8.00
Dispatches in 10 days
EST. delivery charge