For those curious about what happened to Biersach & Niedermeyer, here's what became of the company.
After four generations of ownership under the Biersach family, Biersach & Niedermeyer was sold off in 1999 to the Isbister family. Here is the current company's website:
http://www.genmet.com/about/history/
The siren division (ACA) was sold off in the early 1990s and re-branded as the American Signal Corporation. Production of ACA sirens was gradually phased out upon the introduction of new siren lineups including the Tempest and iForce. Dale Moeller serves as president and CEO. In 1999, ASC moved to a new facility in Milwaukee, WI.
The last ACA siren manufactured was the P-50 (ASC RM-135, later T-135 AC) - it was discontinued in 2007. :P50:
