I remember flying a Be36 and for a while (many trips back to the LAME) the gear warning would sound while in cruise! :o Great for the pax. It wasn't because I was so high that the MP was less than 13" (I think, I have a terrible memory) even with the throttle fully in, but was from the fact the horn is set to sound when the throttle is pulled out a certain distance. In this case the thing was basically stuffed, so even at full throttle, all you had to do was jiggle it and the horn would either sound or stop!
This is like every machine I have flown, if you ignore that landing flap with gear up will sound the horn, it isn’t a set number be it MP, Torque or N1 that will sound the horn, but PLA.
As for how loud is the horn, he/she can get very loud! “Are you going to drop the gear soon?”
