I think my horns are dying and I have wanted something louder anyways. My 3200 has dual car style horns on the arch. I wanted trumpets, then realized they usually have two mounting points, the base and then support for the trumpets. Anyone use trumpets on their radar arch, or do I need the compact style horns?
on my 01 3000 I mounted a single trumpet horn with great results. It had two mounting points also for the base and horn itself. My set up was to glue a piece of starboard to the arch to raise the horn well above the Bimini top that I have up all the time. So the base of the horn gets screwed into the starboard and that is it. No second support and I have not had any problems. Make the base secure and you shouldn't have any problems.
I want dual, though. Quick search found this as a possibility.
Vixen Horns Loud 125dB Powerful Dual Stainless Steel Trumpets Marine Electric Train Air Horn for Boats/RV/Trucks Chrome 12V VXH2112Mar https://www.amazon.com/dp/B015QEQLL6..._GqGdBbPA9A2E1
The horns aim down toward the water. They are typically mounted in approximately a 45 degree down angle. The idea is to echo the sound out over the water in a radius and prevent isolating sound in one direction.
I've seen horns installed on radar arches without any problems.