I finally got rid of the wimpy stock horn on my 2006 Corolla. I decided on a pair of the Stebel Magnums (TM80/2), made in Italy. These things are really loud, yet they’re tuned and have the sound of a big American car. These are not air horns.
One horn is the low frequency, the other is the high. Both horns are mounted on the left and right ends of a 4" "T" bracket that I purchased from Lowe's. The replacement bracket bolts in the exact same place as the original bracket (no drilling). Both horns fit very well this way and clear the radiator and hood latch with room to spare.
I used an in-line 20A fuse wired directly to the hot side of the battery, and a FIAMM brand relay that I picked up at a local auto parts store. I found the terminals I needed at Radio Shack. Everything was hooked up with 12 gauge wire (a pair of these pulls about 14 amps).
If you want to hear what these sound like, go to
www.stebel.it and click onto Products/Elettromagnetics/TM80 Magnum for a sound file.
Installation Photo: