Looking for DEEP LOW Note , NOT LOUD, Sounding Horns

[MrTom]

Hello. From the title I am looking for a DEEP LOW, NOT a LOUD sounding horn.
The volume level of the horn is of no concern to me.
Ideally it would be an electric horn that could replace the stock horns.
Research on the WoLo Bull horn indicates it sounds more like a castrated calf so I am reluctant to purchase one of those.
Have considered a horn with a compressor but that would be the last resort.

Any info for such a horn would be appreciated.

PLEASE don't load up the thread with responses related to horn volume.

Thanks.