Never thought about needing a bell since I don’t hesitate to use my voice. I keep it friendly sounding because my voice can carry and sound a bit aggressive (so I’m told by my girlfriend), so I’ll say something stupid like “ahhh can’t stop!….just kidding!” and then pass, or “on your butt, mind if I pass”
I’ve been wearing earbuds the past couple rides that I was out there solo, and I realize it then becomes up to me to watch my back for passers, since I’m not the fastest guy out there. I’m just surprised that others with earbuds seem so carefree about not being able to hear anything.