I listen to ESPNRadio on Sirius satellite radio while driving to work in the morning. There are plenty of advertisements between segments and most of these ads are offbeat. One ad that I always get a kick out of is that for Prolixus...which is a supplement that promises to add width or thickness to one's 'manhood'. Well, the voice on the radio was that of Something-Something-the Third (I can't remember his name), supposed inventor of this magical pill. Mr. ____ III had a wirey voice, sort of high pitched; a voice that brings to mind images of that pimply faced kid from high school that was always afraid to talk to girls.
A funny thing happened today. Apparently these magical pills not only thicken your...well, you know...these pills also cause a significant deepening of one's voice. Today the voice coming from my speakers once again proclaimed to be Mr. ____ III, the inventor of Prolixus. Well, he didn't sound like he did yesterday or the day before or even last week. His voice was deep; a voice that brings to mind an image of the star quarterback who has extreme confidence and has to shake women away with a stick.
It isn't as if Mr. Squeaky was on one station and Mr. Confident was on another...they were both on the same station proclaiming to be the same person. I find it amusing that no one guiding this marketing scheme brought up the possibility that someone out there may hear the differences in the two voices. If you are trying to convey to the listener that Mr. ____ III actually invented a magic pill, why would you then tarnish any confidence in this message by all of a sudden changing who Mr. ____ III is? The product is suspect at best, don't compound this by engaging in sketchy advertising.
If you are going to pick a spokesperson, make sure that the person stays the same. If you need to change the person conveying your message, make sure that you don't try to pass them off as the same person. This will destroy whatever credibility your product has and will severely dilute your message.