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: Audiophile Headphones for $499

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Sennheiser HD 660S Review: Audiophile Headphones for $499

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Sennheiser HD 660S Review: Audiophile Headphones for $499