Wide variety, short cycles, obvious loops
Its nice to have a wide variety of sounds, but some of the cycles are extremely short and very, very obvious where they restart. Ive only listened to the first 4-5 (rain, thunder, wind, fire). All, but one, had a cycle of no longer than 18 seconds. The 48 second rain cycle is quiet at the beginning and noticeably louder at the end, so distracting when it starts again.
Thunderstorms are normally my favorite. Unfortunately, this cycle is only 18 seconds, so my brain is always listening for specific points in the track, making it difficult to relax, which led me to listen to others & then start timing the cycles.
dbaer1970 about
Sleep Pillow White Noise Sound, v6.5