I'm not a guitar player (though I did take lessons in my youth), but I am a huge Nick Drake fan and have always been haunted by the very unique, dark, and moody guitar tones that he achieved. In this fascinating video by YouTube guitar teacher, Josh Turner, he presents and demonstrates his theory for how Nick got his signature sound.
Spoiler Alert: He identifies these four characteristics that he thinks are the most significant contributors:
1. Small-bodied guitar (probably)
2. "Dead" nickel strings
3. Medium-length fingernails, long thumbnail
4. Classical guitar-style hand position with bent wrist and thumb angle (and playing over the sound hole)
At the end of the video, to demonstrate the sound, he launches into the first part of Things Behind the Sun. It sounded so beautiful, it made my eyes want to roll back in my head. And made me immediately run to the original as soon Josh's video was over.
If you are also a fan of Drake's, you'll want to check out Remembered for a While, the the lovingly curated scrapbook of all things Nick that his sister, Gabrielle Drake (perhaps best known as the purple-haired Lt. Ellis on the cult-fave 70s British TV series, UFO) put together. Here's the review I wrote of it here on Boing Boing.