The company was founded in 1945, just a few weeks after the end of World War II, by Fritz Sennheiser (1912–2010) and seven fellow engineers of the University of Hannover in a laboratory called Laboratorium Wennebostel (shortened, "Lab W").
The laboratory was named after the village of Wennebostel in the municipality of Wedemark to where it had been moved due to the war.
Its first product was a voltmeter.
Lab W began building microphones in 1946 with the DM1, and began developing them in 1947 with the DM2.
By 1955, the company had 250 employees, and had begun production of many products including geophysical equipment, the Noise-Compensated microphone (DM4), microphone transformers, mixers, and miniature magnetic headphones.
Labor W was renamed 'Sennheiser electronic' in 1958.

In the late 1950s/early 1960s, Professor Sennheiser met a gentleman in the hospital by the name of Thomas Schillinger.
 Mr. Schillinger was tasked with starting Sennheiser's presence in the United States.
 The culmination of this was a technical Oscar Award in 1987 at the 59th Academy Awards (see below).

Sennheiser was transformed into a limited partnership (KG) in 1973.
In 1980, the company entered the aviation market, supplying Lufthansa with headsets.

The company began producing modern wireless microphones in 1982, the same year when founder Fritz Sennheiser handed the management of the company over to his son, Jörg Sennheiser.
In 1987, Sennheiser was awarded at the 59th Academy Awards for its MKH 816 shotgun microphone.

Also in 1991, Georg Neumann GmbH, Berlin, which builds studio microphones, became a part of Sennheiser.

In 2003 Sennheiser entered into a joint venture with the Danish company, William-Demant-Holding, a specialist in hearing aids, diagnostic technology and personal communication.
Sennheiser Communications A/S was founded.

2005: Sennheiser acquired the speaker manufacturer Klein + Hummel.

Daniel Sennheiser, grandson of the founder, joined the company in 2008.
In 2010 his brother Dr. Andreas Sennheiser also did so.
Both are shareholders of the company.

On July 1, 2013, Daniel Sennheiser and Andreas Sennheiser were promoted to the position of CEO responsible for Sennheiser electronic GmbH & Co. KG.

In 2014 Sennheiser founded the new subsidiary "Sennheiser Streaming Technology GmbH (SST)", which develops streaming solutions for software and hardware.

In 2019 Sennheiser acquired a majority stake in Dear Reality, a company that specializes in spatial audio algorithms and VR/AR audio software.
The company was founded in 1945, just a few weeks after the end of World War II, by Fritz Sennheiser (1912–2010) and seven fellow engineers of the University of Hannover in a laboratory called Laboratorium Wennebostel (shortened, "Lab W"). The laboratory was named after the village of Wennebostel in the municipality of Wedemark to where it had been moved due to the war. Its first product was a voltmeter. Lab W began building microphones in 1946 with the DM1, and began developing them in 1947 with the DM2. By 1955, the company had 250 employees, and had begun production of many products including geophysical equipment, the Noise-Compensated microphone (DM4), microphone transformers, mixers, and miniature magnetic headphones. Labor W was renamed 'Sennheiser electronic' in 1958.
In the late 1950s/early 1960s, Professor Sennheiser met a gentleman in the hospital by the name of Thomas Schillinger.  Mr. Schillinger was tasked with starting Sennheiser's presence in the United States.  The culmination of this was a technical Oscar Award in 1987 at the 59th Academy Awards (see below).
Sennheiser was transformed into a limited partnership (KG) in 1973. In 1980, the company entered the aviation market, supplying Lufthansa with headsets.
The company began producing modern wireless microphones in 1982, the same year when founder Fritz Sennheiser handed the management of the company over to his son, Jörg Sennheiser. In 1987, Sennheiser was awarded at the 59th Academy Awards for its MKH 816 shotgun microphone.
Also in 1991, Georg Neumann GmbH, Berlin, which builds studio microphones, became a part of Sennheiser.
In 2003 Sennheiser entered into a joint venture with the Danish company, William-Demant-Holding, a specialist in hearing aids, diagnostic technology and personal communication. Sennheiser Communications A/S was founded. 
2005: Sennheiser acquired the speaker manufacturer Klein + Hummel.
Daniel Sennheiser, grandson of the founder, joined the company in 2008. In 2010 his brother Dr. Andreas Sennheiser also did so. Both are shareholders of the company.
On July 1, 2013, Daniel Sennheiser and Andreas Sennheiser were promoted to the position of CEO responsible for Sennheiser electronic GmbH & Co. KG.
In 2014 Sennheiser founded the new subsidiary "Sennheiser Streaming Technology GmbH (SST)", which develops streaming solutions for software and hardware.
In 2019 Sennheiser acquired a majority stake in Dear Reality, a company that specializes in spatial audio algorithms and VR/AR audio software.
Sennheiser