Just drop the "sound" folder in your Fallout 4/Data folder, or use NMM. I'm not sure if this is NMM compatible though :P

Credits:
ChocolateUnunoctium - Synthesizing and looping
Fiddlestickz - Tutorial on looping
Increpare - BFXR (the synthesizer)

Also, incase you're wondering, BFXR isn't all that hard to use, and the web page makes it clear that you own full rights to the created sounds. Go check it out, maybe donate to the creator.