[1] The company is focused on three audio equipment business segments – Automotive, Consumer and Professional – offering products under company-owned brand names including AKG, Bang & Olufsen Automotive, Becker, Crown International, dbx, DigiTech, JBL, JBL Professional, Infinity Systems, Harman/Kardon, Lexicon, Mark Levinson Audio Systems, Soundcraft and Studer.

HARMAN International corporate customers include Apple,[2] Audi,[3] BMW,[4] Cadillac,[5] Ford,[6] Genesis,[7] Google,[8] Hyundai,[9] Kia,[10] Lexus,[11] Lincoln,[12] Mercedes-Benz,[13] Ram Trucks,[14] Toyota,[15] Volkswagen.

[17] After graduating from college, Sidney Harman's first job was at the David Bogen Company as an engineer where he designed public-address systems.

Early integrated receivers (with a tuner, preamplifier and power amplifier) were an attempt to create, improve and produce high fidelity performance in a single unit.

By 1957 the company offered a wide range of audio equipment, including console receiver units, stand alone tuners, amplifiers and a number of integrated receivers in varying levels of output wattage and features, all within three price ranges - the "Standard", the "Deluxe" and the "Custom" lines.

[29][30] The company began offering an unconditional one year guarantee on parts and labor on all Harman Kardon equipment.

Harman steadily grew the company into a consumer audio juggernaut in the home, professional and automotive markets producing speakers, amplifiers, noise-reduction devices, video and navigation equipment, voice-activated telephones, climate controls and home theater systems.

[34] In 1959, Harman Kardon marketed the Citation II, an early ultra wideband stereophonic tube amplifier.

[35] The company promoted their philosophy of designing high fidelity sound using amplifiers that provided widest possible audio bandwidth.

In 1970 Harman Kardon introduce the CAD5, the world's first stereophonic cassette recording deck with Dolby B-type noise reduction.

When Harman took office in 1976, he sold his company to conglomerate Beatrice Foods for $100 million[36] to avoid a conflict of interest.

[39] The amplifier was designed by Finnish engineer Matti Otala [fi] who discovered transient intermodulation distortion (TIM) in 1970[40] and worked to mitigate its effects in the following years.

On March 11, 2017, Samsung Electronics announced the acquisition of Harman for a reported purchase price of US$8 billion.

[47] Harman Kardon supplies audio equipment to several vehicle manufacturers including BMW,[48] Dodge,[49] Hyundai,[50] Kia,[51] Mercedes-Benz,[52] Mini,[53] Subaru,[54] Volvo,[55] Volkswagen.

A pair of Harman Kardon transparent spherical speakers, along with the Apple G4 Mac Cube for which they were designed and produced from 2000 to 2001, are housed in the permanent collection of New York's Museum of Modern Art.

In 2017, Harman Kardon released a smart speaker, powered by the Microsoft Cortana virtual assistant, called Invoke.

In August 2018, Harman Kardon announced the Citation 500, a US$600 smart speaker running the Google Assistant.