sorry - might be a bit of a Newbie question, but after researching via Google I am even more confused.
I have Jon Severinsson's ffmpeg PPA installed on Ubuntu 14.04 and want to replace it with mc4man's PPA. How do I purge the old PPA correctly and clean, so I can get the new one?
Is it
sudo ppa-purge ppa:jon-severinsson/ffmpeg
and then
sudo add-apt-repository ppa:mc3man/trusty-media
sudo apt-get update
sudo apt-get dist-upgrade
?