Sennheiser HD 660S Review: Audiophile Headphones for $499

Sennheiser's HD 660S open-back headphones offer impressive performance, but you'll need to invest in a good audio source to get the most of out them.

Sennheiser HD 660S review - SoundGuys

Sennheiser Consumer Audio HD 660 S - HiRes Audiophile Open Back Headphone

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Sennheiser HD 660S headphones review

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Sennheiser over-ear & on-ear Headphones

Natural, relaxed, high-fidelity sound with extra sub bass: Ultra-light aluminum voice coil with 300-ohm impedance for excellent impulse response and

Sennheiser Consumer Audio HD 660S2 - Wired Audiophile Stereo Headphones with Deep Sub Bass, Optimized Surround, Transducer Airflow, Vented Magnet