The sounders from the DS 10 series can be used for tough demands under industrial conditions and as universal alarms. The sounders which are suitable for use both indoors and outdoors, generate warning signals in 31 different tones that can be selected with the aid of an internal switch. Optionally, a maximum of 3 additional tones can be switched to using an external controller. In addition to the factory settings, the tone combination can be individually selected by on-site programming (tone 32). Custom versions are available for special applications. The DNV version is especially resistant to shock and vibration.