Using Music Commercially
An important element of marketing videos is your background music.
It sets the mood and tone of your brand and message, and can take your YouTube and other video marketing to the next level. Says StoreYaBlog with other useful music related information and music.
A royalty is a payment per use payment but may have other payments attached like a one off type.
It belongs to the public and can be used FREE with no requirement to give credit.
You are going to get permission to use it but you may have to use it only a certain number of times or pay or mention credit. That is called "having a licence."
Out of Copy Rite
Old music in manuscripts may be out of any type of copy rite but have restrictions because a band or orchestra have rendered an interpretation theirs. Start of copy rite is complicated but is probably OK if the composer has been dead for more than 70 years. In the United States, any music composed before January 1, 1924, is generally considered public domain. (Sentence from Wikipedia. Do use this Platform I recommend it.)
I will be using a synthesizer in order to produce my own version FREE