The company was founded in London, England, in 1972 by Dr. Martin L. Borish, an electrical engineer with a PhD in physics.
Its most famous product is the NAD 3020 of the late 1970s, an integrated amplifier designed by Bjørn Erik Edvardsen, which was highly rated by several British magazines.

NAD's philosophy is to include only really useful features for aesthetically unobtrusive designs compared to other competitors' products.
NAD was one of the first audio manufacturers to outsource the manufacture of its products to East Asian electronics factories.

NAD was acquired by the Danish company AudioNord in 1991 and subsequently sold in 1999 to the Lenbrook Group of Pickering, Ontario, Canada.

NAD focuses on the concept of "effective power" and its amplifiers claim to offer generous headroom, meaning that they can be capable of delivering bursts of dynamic power far in excess of their rated RMS power. The key to this feature requires the use of a flexible power supply that stores significant standby current for quick release at times of high musical load. Originally developed at NAD by Phill Marshall, the various incarnations of this design have been associated with different names over the years, including Power Envelope and recently PowerDrive.

Other benefits of this approach include the fact that amplifiers using this technology can drive complex, low impedance speaker loads in real life, compared to the simple 8 ohm resistor typically used to calculate advertised powers, and the fact that the circuitry in this approach requires less cooling, while maintaining the ability to drive complex impedance loads as low as 2 ohms.

Two Bluesound products, Pulse and Powernode, incorporate NAD's direct digital technology, which is also integrated into its line of receivers, such as the NAD 758v3 and NAD 777v3.