I find my bell is much more effective than calling out, the sound actually carries fairly well and it seems to get attention whereas many people drown out voices. Whenever I go around a known blind or obscured corner I ring it, also at intersections and sometimes to let my ride group know where I am if we get strung out. If I don't have a bell is yell "rider" but I have had a few close calls with that. A lot of hikers and bikers have thanked me for having the bell.
Amanda
2011 Specialized Epic Comp 29er | Specialized Phenom | "Marie Laveau"
2007 Cannondale Synapse Carbon Road | Selle Italia Lady Gel Flow | "Miranda"
You don't have to be great to get started, but you do have to get started to be great. -Lee J. Colan