If I create a song with my own chord progression, key and tempo, but it is entirely composed of realtracks, which I have generated repeatedly to find the one that fits best, and then used individually by exporting the .wav files and remixing them in my DAW...

Then is it a violation of the licensing agreement if I put that song onto a commercial album, without adding any other instrument layers to it?

You can't copyright a chord progression. If you could then every 1-4-5 blues/rock/country song or 1-6-4-5 song or any other common chord progressions that hundreds (thousands?) of songs use would all be copyright violations.

You can copyright melodies, lyrics and musical licks that go over a chord progression.

PG's Real Tracks/Drums are great sounding but completely generic backing rhythms and grooves. Nothing to copyright there so have as much fun as you can with no worries.

And Forum Search is your friend. Both these subjects, copyright and using the RT's royalty free come up over and over, sometimes weekly it seems. Click on the Forum Search tab>Advanced>All Forums>enter copyright and leave it at the default 5 years to start. Tons and tons of multi page threads going back 5 years from now and nothing has changed in the law since 1998 but starting last year old stuff from 1923 is moving to the public domain.

Here's something you might like to read:

https://fairuse.stanford.edu/overview/faqs/law-changes/

Bob

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