Opinions expressed by Forbes Contributors are their own. Technology journalist specializing in audio, computing and Apple Macs. When Sennheiser announced that it would be licensing the development ...

Some companies—such as Sennheiser—produce some amazing ... drivers weren’t good enough for use in a dual-driver arrangement with headphones because of size restrictions.

Their styling might be slightly anonymous, but there’s nothing forgettable about how these Sennheiser headphones sound. 42mm full-range dynamic drivers deliver a listen that’s bold, detailed and ...

There is a 38mm full-range dynamic driver inside each earcup ... Each of the HD 660S2 headphones is physically wired, using Sennheiser’s familiar two-pin connections. There are two 1.8m cables ...