Did Whelen ever offer dual lo-pro speakers on an Edge as a regular production option, or was this lightbar a homebrew?
So sorry for the late answer.
These 52 inch edges were constructed by the Dutch representative for Whelen, the firm HONAC. This model was used in second half of the '90s, begin 2000 on a lot of Chevy Ambulances in the Amsterdam area and some other cities.
The setup was either with 4 Turbotube strobes on the corners or the 4 Turbotubes all facing forward.
In the front center an illuminated sign was mounted, white plastic with red stickers in the word AMBULANCE.
The dual speaker setup was requested by the company that builds the Chevrolet ambulances, because they were using the German Wandel&Golterman WA50 tri-tone siren amplifier that delivered 200Watt output. Put 2 SA40's on the Edge and let the WA50 tri-tone siren roar.
I had 4 of those in my collection years and years ago, traded some, rebuild some, now I only have one original setup like that hanging just right there.
Here's a Chevy ambulance with that Edge model on top from those days, the chevy was donated to an animal-ambulance organization after which they switched out blue for amber lenses
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pic © R. Visser
They even had AdvantEdges with this dual speaker setup back then
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