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Revision as of 04:53, 14 June 2018 by Pi User5(talk | contribs)(The 2011 version of the page for the Vortex series has the DB output listed for the R2-R4 models so let's use them.)
The Vortex-R Series is a line of electronic sirens produced by Whelen Engineering. They are essentially 4000-series siren heads with Type-1 control cabinets that lack voice capability, much like the Omni-Alert series. Unlike the 4000 Series, one- and two-driver models were offered. Older models have a large fin mounted on the rear of the driver assembly, a trait inherited from the 4000 series.
