MyNoise is the best. Stéphane seems like such a respectful, down-to-earth guy. I don’t pay for many subscriptions—I go out of my way to avoid them—but I put some good money into MyNoise regularly because it’s been such a valuable service. It’s optional—I don’t actually use many of the paid features—but I appreciate it so dang much.
Boston College's FM station WZBC has a program No Commercial Potential, which plays lots of experimental sounds, some of it sounds like MyNoise Flying Fortress. Everything depends on the DJ and their mood, but some of it has this vibe.
HAHA - I came here to say the same (I pay for it as well, and I love the flying fortress with radio chatter...
I just spent some time adding layers of sound to the actual ATC chatter, then I add individual layers, like distant thunder, b29, singing bowls and rain etc...
