Bonneville America Forums Forums Technical Forums Accessories High or Low tone aftermarket horn?

I want to replace my stock horn with a horn cars can hear. This horn will fit in the stock location of my BA with no mods but I don't know whether to get the high tone or the low tone.

Horn link - http://ridesafer.com/store/item/fpc1/Horns/Fiamm_HF-90_High_Performance_Horn.html