Hey, I'm wondering, could anyone describe what kind of waves we observe between 20 - 200 Hz? I find this spectrum very interesting, as it includes many interesting aspects. Electricity we use are normally from 50-60 Hz. Am I right that somewhere around 100 Hz light, although not visible, start to operate? Could anyone describe the waves seen here to me? Obviously it is not visible light, as that's not before around 400 Hz, but it is still photons, isn't it? This spectrum also corresponds with the highest half of our audible range, as well as the highest forms of beta waves, and the whole spectrum of gamma waves. I would be highly interested in hearing every detail concerning this range. In terms of quantum mechanics, is that spectrum involved in some of the phenomena we can observe? Thanks in advance!