It’s a “phew, phew, phew, phew” sound in an endless steady rhythm. Hearing it gives one sensations that appertain to temperature change, and also a sense of movement. It sometimes can become an ignorable drone for it happens so frequently and continuously. It has a high frequency, but also a lower one that sounds like a monotonous moan.
The noise often impedes with my thinking waves, which I particularly enjoy when I am working on one task, for the noise helps removing other thoughts happening in my mind when I am trying to concentrate. The noise also has uniformity in a small space; it sounds very similar everywhere in a room wherever one stands. Furthermore, the noise vibrates in a way that reminds me of humming. I can sense a tight sound wave and, below, an elongated one, both periodic, and both melodic in my ears.
– Ruby W.