They sold not only Harmony products, but instruments under the Sears name, Silvertone, and a variety of trade names—Vogue, Valencia, Johnny Marvin, Monterey, Stella, and others.

[citation needed] In 1940, after Kraus had a conflict with management, he left, but then bought enough stock to restart the company independently.

The Harmony brand peaked in 1964–1965, selling 350,000 instruments, but low-end foreign competition led to the company's demise 10 years later.

Many of the instrument amplifiers badged with the Harmony name were manufactured by "Sound Projects Company" of Cicero, Illinois.

In the early 2000s, an unrelated company, the Westheimer Corp., based in Lake Barrington, Illinois briefly imported "reissue" Harmony guitars.