An audible signal device which includes a DC to DC converter is provided. A group of work machines is further provided, including at least two work machines having electrical systems with different operating voltages. First and second audible signal devices are coupled with the first and second electrical systems respectively, wherein the second audible signal device is interchangeable with the first audible signal device and at least one of the devices includes a DC to DC converter. A method of assembling a plurality of dissimilar machines, each including an interchangeable audible signal device is further provided.

 
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