Credited to Japan. The Walkman Archive notes a competing claim that Andreas Pavel's Stereobelt was the first portable stereo player and that Sony did not originate the idea. Sony's product was the first to reach a mass market.
How it began
Sony co-founder Masaru Ibuka liked to listen to stereo music on flights but found the company's TC-D5 recorder too heavy. Before a trip to the United States he asked for a Pressman, a palm-sized monaural recorder, to be fitted with stereo circuits and no recording function. Kozo Ohsone's tape recorder department made the modification. Ibuka showed it to chairman Akio Morita, who in February 1979 gathered young employees and set a goal of a product in stores before the summer break. It was announced on June 22 and went on sale in Japan on July 1, 1979.
Before it existed
Sony had sold Japan's first tape recorder in 1950 and its first Compact Cassette recorder, the TC-100, in 1966. By the late 1970s cassettes were common in home and car stereos and in radio-cassette players. Recorders light enough to carry while walking had only monaural built-in speakers. Sony's stereo TC-D5 of 1978 weighed about 1.7 kilograms.
How it works
The first model, the TPS-L2, reused the internal mechanism of the Pressman, with the recording function removed and stereo playback added. It was paired with new open-air headphones that weighed about 50 grams, when most headphones weighed 300 to 400 grams. It had two headphone jacks so that two people could listen, and a "hotline" button that switched on a small microphone so they could talk over the music.
Who pushed back
Many inside Sony doubted the product, arguing that a tape machine that could not record would never sell. The media response to the launch was mild, and only 3,000 units sold in the first month. Sony staff rode Tokyo's Yamanote train line wearing the device to show it in use. Some in the company also thought the name was ungrammatical English, and it was first sold as Soundabout in the United States and Stowaway in Britain.
What changed first
In late July and August 1979 the first batch of 30,000 units sold out, and production struggled to keep up with demand. The Walkman name spread abroad on its own, and Morita decided to use it everywhere. By 1986 the word was listed in the Oxford English Dictionary.
What lasted
Sony reports that over 400 million units were sold in the forty years to 2019, counting cassette, CD, MiniDisc and flash memory models. The company credits the first Walkman's headphones with making people walking with headphones an everyday sight, and the headphone line went on to produce the first in-ear headphone in 1982.
