Sennheiser specializes in equipment for both the consumer and professional audio markets, including microphones, headphones, and loudspeakers.

The company was founded in 1945 shortly after the end of World War II by Fritz Sennheiser[2] and seven fellow University of Hannover engineers.

Still in production more than 60 years after its introduction, the MD 421 is considered an industry standard, with more than 500,000 units having been produced.

At the same time, the company launched the Sennheiser Media record label with the release of A Bu's first album.

[23] In May 2021, Sonova Holding AG, a Swiss cochlear implant and hearing aid manufacturer, acquired Sennheiser's consumer audio division, which produces a range of headphones and home entertainment speakers, for €200 million.

The professional audio division also produces solutions for business communication, such as presentations, conferences, meetings, visitor guidance, hearing support, and the education sector.

[31] Sennheiser has research and development sites in Germany, Denmark, Switzerland, Singapore, and the United States.

[33] The company has factories in Wennebostel (Wedemark, near Hannover); Tullamore, Ireland (since 1990); Albuquerque, New Mexico (since 2000), and Brașov, Romania (since 2019).

[34] The factory at its Wennebostel headquarters focuses on products for the high-end consumer and professional audio markets.

Sennheiser now has seven stores in Berlin, San Francisco, Singapore, Kuala Lumpur, Mexico City, and Sydney and at its headquarters in Wedemark.

[38] Sennheiser created the first augmented audio listening accessory for Magic Leap’s AR/VR goggles, the AMBEO AR One.