Sennheiser HD 660S2 review: New approach yields stellar results
Sennheiser's new open-back, audiophile-quality over-ear headphones deliver an awesomely open sound stage and are decided not neutral tuning.
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Sennheiser HD 660S2 Review
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Sennheiser HD 660S2 Dynamic Headphones - Magnificent Musicality — Audiophile Heaven
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