This was created using paulstretch [1], a program to transform normal audio using extreme stretches. I've tried it on a few songs I liked and it does really an excellent jobs of creating extremely fluid ambiances.
The triple parentheses on the first video is a nod to Sunn O))) [2], an American drone / noise / ambient metal band which features super long songs with droning saturated guitars (playing on vintage cranked up to 11 Sunn Model T amps) and usually no drums. One of my favorite songs from them and perhaps one of the best introduction to their music for the non-initiated is titled Alice [3], though perhaps it's not as representative of their music as, say, Ra at Dusk [4]. (Sunn O))) was heavily influenced by the pioneer drone metal band Earth, and their mindblowing album Earth²: special low frequency version [5]).