A former Harmony employee reported a different scheme: "We worked 10 hours, 5 days a week, any 8 more every Saturday. I believe the "F" and "S" on the serial numbers was for first or second shift." Harmony was also an original equipment manufacturer (OEM) for several other brands, most notably Silvertone.OEM models were typically very similar to a Harmony instrument but with cosmetic differences.

The Harmony Company actually was always behind on orders, not that they were slow in building instruments, it was sheer demand outpacing the workforce.

Harmony had the choice of either enlarging their operation to meet the demand, or let foreign makers take up the slack.

They continued to turn in impressive annual sales figures right up till the company was dissolved.

In 1930 the Roy Smeck Grand Concert and Hawaiian models were unveiled and in 1931 the Vagabond guitar line was first produced.

The management of Harmony were too conservative and decided not to expand their operation.

This allowed the floodgates to open and the world saw Asian companies take the low to medium grade instrument market away from the American companies. in Chicago ceased operations and had a huge three day auction. In 2009, the Harmony trademark and all intellectual property was acquired by Westheimer corpoaration in Northbrook , IL.The Harmony Company of Illinois, United States, manufactured a wide variety of musical instruments which were popular during most of the 20th century.This article is devoted to documenting these instruments.Thus began the most successful American made stringed instrument producer ever.Wilhelm immigrated to America to work for the Knapp Drum Company of Chicago. In 1915 Harmony was the first large scale ukulele builder.In 1928, Harmony introduced the first of many Roy Smeck models, and went on to become the largest producer in the U. They sold 250,000 pieces in 1923 and 500,000 in 1930, including various models of guitars, banjos, and mandolins.