I left the field Air Revitalizer playing in my room when I was away, i. E. I couldn’t hear the sound at all.
Yet just now I suddenly remembered the guidance that in order for the fields to work we have to at least hear them consciously. Yet at the same time it seems that many testified that fields such as Water Oxygenator, Plasma Drink Charger, Negative Ion Generator or the Far UVc Bergamot and Sandalwood etc. work while they were away.
Regardless the functions of each field, the production mechanism behind is the same. Is being heard necessary? Why those fields work without being heard?