unless the bicycle is equipped with a bell or other device capable of giving a signal audible for a distance of at least one hundred (100) feet
I definitely think that the human voicebox is such a device! Cars with rolled-up windows and a stereo blasting may not hear a bike bell but they sure can hear me yelling 'HEY!' (stopped one from running into my front wheel last night.)

The laws in CO are pretty practical, probably thanks to a lot of bicycle advocacy. But you can definitely get a DUI for biking under the influence, and I know a fair number of people that have been ticketed for failing to have a front light.

Anne