US record label Relapse Records release an annual sampler album each year which you can download for free/name your price. Just put 0 in as your price along with your email address and a download link will be sent to you.
Relapse generally specialise in hardcore & heavy metal music with bands like Obituary, Dying Fetus, Death, The Obsessed and King Woman but there are also a couple of songs from Steve Moore & SURVIVE (of Stranger Things fame).
You can still download their past samplers here:
https://relapsesampler.bandcamp.com/music
2016 (41 tracks)
2015 (36 tracks)
25 Years of Contamination (194 tracks)
2014 (26 tracks)
2013 (26 tracks)
2012 (26 tracks)
Might be worth including in the description that they're a Metal orientated label.