Module C - Slide 13
Right now for the audible walk indication, there are two choices and those choices depend on the location of the APS pushbuttons.
You may not understand why that is. Mainly, distinguishing sound can be difficult.
Traffic signals are carefully oriented so you don’t see them from the wrong place; we need to think about the same issues in terms of audible signals. Two different sounds (ie.Cuckoo/chirp) didn’t work because people don’t always know what direction they’re traveling and don’t remember which sound is for which direction.
The standard now is that if pushbuttons are separated by more than 10 feet, the location clarifies which crosswalk is being signaled so the tone (rapid tick) walk indication works well. If two pushbuttons are closer than 10 feet to each other, it’s hard to distinguish which one is sounding by direction or location, so specially programmed speech messages and additional features are needed.
Research has found that speech messages are not understood by a proportion of the population in the presence of traffic noise, particularly older people, so it’s not the first choice, even though it sounds good in a conference room. Hopefully, eventually, as we get more consistent separation of pushbuttons and location of pushbuttons beside the curb ramp/crosswalk they serve, we can go to one sound for walk everywhere (which will be easier to understand and maintain).