For instrumental music with no vocals, try: Wide Eyes, Invent Animate (their instrumental versions), Modern Day Babylon, I Built the Sky. These aren’t quite Death Metal, but they have really complex guitar and drum pieces.

For with vocals: Sea in the Sky, Ignea, Unleash The Archers, Corelia (also has instrumental version of their 1 album)

We have a big maple in our yard and more through the neighborhood. The sound of wind running through their leaves is very calming.

Unfortunately, this is exactly what is turning (and has been turning) the US into a shithole country.