The 1930s saw major advances in pinball design with the introduction of electrification. A company called Pacific Amusements in Los Angeles, USA produced a game called Contact in 1933. Contact had an electrically powered solenoid to propel the ball out of a bonus hole in the middle of the playfield. Another solenoid rang a bell to reward the player. The designer of Contact, Harry Williams, would eventually form his own company, Williams Manufacturing, in 1944. Other manufacturers quickly followed suit with similar features. Electric lights soon became a standard feature of all subsequent pinball games, designed to attract players.
By the end of 1932, there were approximately 150 companies manufacturing pinball machines, most of them in Chicago. Chicago has been the center of pinball manufacturing ever since. Competition among the companies was strong, and by 1934 there were 14 companies remaining.
During WWII, all of the major manufacturers of coin-operated games turned to the manufacture of equipment for the war effort. Some companies, like Williams, bought old games from operators and refurbished them, adding new artwork with a patriotic theme. At the end of the war, a generation of Americans looked for amusement in bars and malt shops, and pinball saw another golden age. Improvements such as the tilt mechanism and free games (known as replays) appeared.