There is a famous British rock hit by Ian Dury titled "Reasons to be Cheerful Part 3." Well whehter there are ther two parts or more, when you need to represent reasons for any kin of joy or cheerfulness, and you want your potential audience to feel the same, you can simply resort to a happy go lucky voice.
You or your company, social group or political organization has done well, you or somebody in your family has won a prize or any other 1001 reasons can be a good occasion to announce it loud and clear. To transform such feelings through a video/audio message, an add or just a simple announcement, you would need a voice that transforms such feelings in a best possible manner, and it has to have that happy go lucky sound to it.
The use of a happy g voiceo lucky voice is directed to practically any audience that needs to share your joy and project optimism. It can be a wider one, with which you need to xhare a political/social message, or excellent results your company has achieved in a certain period of time. It can also be a new product you are putting on a market about which you are very excited about. But then it could be a smaller circle of family and friends whith which you want to share the joy of a newborn family member, a wedding or another happy personal event.
Happy go lucky voice is always cheerful, often reaching higher pitched registers. It is also sometimes even more upbead that just 'the simple' happy voice.