Personally, when I've been walking and heard a bell, it has taken me a few seconds to put it into context and realize "Oh, it's a (quaint old-fashioned) cyclist..." and respond. They are not the norm here, and I don't like them as a pedestrian/dog walker, nor as a cyclist who rides a MUP a few times a week. The only time I've felt a bell had value was where there was a tunnel under a road, which immediately crossed another path. I had my leashed dog, heard a bell in the tunnel, and knew to watch out. That was 'gentler' than someone shouting for general purposes going through the tunnel, messing with the evening vibe.

IMO, the range of a bell is too short. At 18-20mph, you are going to be running someone down before they hear a bell, interpret it, and react. I know that a walker is not likely to make out my first couple of words, but they will get their attention, so I use a series of phrases, in rapid succession, along these lines:

"Bicycling coming up."
"On your left."
"Plenty of room." (assuming there is)
"No need to do anything"
"Thank you very much!"

I know how to "project", and I do everything I can to get them to just keep walking and skooch over a bit if need be.

It cracked me up last Saturday when our ride was re-grouping along the side of the road, and a cyclist came past, on a road bike, ringing a bell. We were all stopped, had obviously seen her, and yet she felt the need to ring her bell as she went by. Huh? I also noticed that, when we got back going and went by her, saying good morning, she didn't reply. Damned roadies. :-)