If you're a gamemaster who wants to add atmosphere to the game by using music, be it background music or effects, you might be searching your media library or the web without finding the 'right one'.
The problem with this kind of music is that it often doesn't fit the situation or the selection is simply too short to enrich your game. So the more resources you take into account, the higher is the chance that you got a fitting song or effect in your repertoire.
So recently I stumbled up two links that seem very promising if you're looking for RPG background music:
The page Tabletop Audio offers a very good selection of atmospheric and ambience music especially designed for RPGs. The various categories make it easy to make a good selection for your next session if you for example plan to play in a 'River Town' or play on a 'Volcano' scene.
There are of course major categories to distinguish between Fantasy-, Sci-Fi- or Horror-themed music.
The next link, that you should have a look at, is the Dungeons and Dragons Tabletop Spotify playlist that was set up by kingslayer133. The selection features about 500 songs that sound a little bit more medieval and as the title of the playlist says, seems to be a good fit for D&D gamemasters.