Other, more technical reasons that are put forth in the collective social wisdom, that is found on the Internet, was that perhapsthe phones needed better microphones; they needed to amplify sound better; or that cell phones needed to use better data compression for better audio quality. I have another theory as to why many people speak loudly when using cell phones. Most, if not all, cell phones do not feed your voice back to your ear speaker like a wired or cordless phone does. This subtle, yet important difference is most likely driven by the need/desire to extend the battery talk and standby life of a cell phone for
as long as possible. However, this difference can create a mistaken impression in the user that the phone is not picking up their voice and that they must speak up for the badly designed microphone to capture what they are saying.
I have found through personal experimentation that I can successfully carry on a conversation over a cell phone while speaking so softly that I cannot readily hear my own voice. As more people opt out of their land lines and use cell phones exclusively, this social “problem” may peacefully resolve itself because there will be no difference in the voice feedback.
The point of this exercise is to get you thinking about the possible consequences, both technical and social, of the engineering trades you must make in your day to day decisions. The other thing you can do is educate your users when decisions you have to make may create disconnects in expectations, like the voice feedback implementation between wired, cordless, and cell phones. Rather than get mad at the user who is unconsciously trying to accommodate a perceived technical limitation, find a way to teach them how to recognize the difference and behave differently in each context. Until people understand that there is a difference in the voice feedback in their various phones, they are likely to continue to try to inappropriately and unnecessarily adjust for the perceived technical shortcomings of their cell phone.
英文原文地址：http://www.edn.com/blog/1890000189/post/170007217.html