I'm having trouble identifying what my horn on my Mercedes 1989 300CE looks like. Used to have a nice two-tone sound, now sounds higher pitched monotone. How do i check for loose connections, and what does the horn look like?

they are snail shaped and bolted to the support behind the front grille.

__________________
2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)