If you haven't gotten rid of the weak factory horn yet you should. I changed mine this morning for the FIAMM Highway Blaster (#72112 Low F-Tone) this morning and it's a great improvement. At least a few times a day it seems like I'm laying on my horn because some ******* is trying to switch lanes into my car on the highway and usually I have to lay on the horn for a while before they hear. There should be no problem for them to hear now!
2006 Vibe (base) - Platinum Silver, 5 spd, ABS, Power Package, Infinity Speakers, Dynomax muffler, Cosmo SR intake - SOLD