Copyright protects your songs under the usual copyright laws. Derivative works and downloads are only possible with your express permission. If you are part of a collecting society this is the only option you can choose for your work.
What does it mean for my sales?
Under Copyright, streaming of your songs is still free, however you can decide whether you want to offer free downloads of your songs or whether you want to sell them. Collecting societies do not allow free downloads, so this option will not be available if you are a member. You can determine the prices of your songs and albums yourself.
What does it mean for rightclearing?
Potential customers must buy licences to be able to use your work.
If your music is licensed under Copyright, the rightclearing base licence contains the right of use as well as the rights to create derivative works. Clients can change your work and use them for their non-commercial projects.
With the rightclearing advanced licence, which is more expensive, the client can acquire the right to use your work commercially.