It is recommended that you specify a character set early so that your Joomla page loads faster so why not do it before the page is even served up! You can do this by setting a default character type in a .htaccess file?
I tried a number of different lines of code before I found one (here) that worked on my host's server. It is:
This is especially important to add to your .htaccess file if you have removed the <meta http equiv> tag as described here.