Sennheiser HD 400 PRO Open-Back Studio Headphones

The HD 400 PRO is an open-back reference headphone built for mixing and critical listening in the home or project studio. Its transducers are mounted at an angle inside the ear cup rather than firing straight on, a layout meant to replicate how a pair of studio monitors sits relative to a mix position, so stereo width and depth translate more naturally than on a headphone with flat-facing drivers.

A dynamic driver covers 6 to 38,000 Hz with a neutral tuning aimed at accurate mix decisions rather than an exaggerated bass lift, and the open-back design keeps long sessions comfortable while letting outside sound in. The headphone ships light at 240 g with velour padding for extended wear, and includes both a 3 m coiled cable and a 1.8 m straight cable terminated in a 3.5mm connector so it can serve a rack-mounted interface or a laptop with the same headphone.