This is "Dr. Andonut's Lab" from the Super Nintendo game Earthbound (MOTHER 2) soundtrack, only it's entirely played on acoustic guitar.
Extended to 30 minutes in length for studying, meditation, and / or zone out purposes.
At the beginning, you hear me pluck the opening chord. An acoustic guitar can't sustain infinitely, so I ran the plucked chord through a compressor with a long release and rode the gain dial, then I duplicated the resulting processed chord, continuously adding fades to make the chord sustain throughout. I was surprised how much the resulting sound resembled an organ drone. If you listen closely, you can hear an audio book on the immune system playing in the other room that accidentally was picked up on the microphone used to record the guitar.