Even in the absence of all anthropogenic RF noise, the noise floor on larger channels is higher. Specifically, I'm thinking of thermal noise: https://en.wikiped

Even in the absence of all anthropogenic RF noise, the noise floor on larger channels is higher. Specifically, I'm thinking of thermal noise: https://en.wikipedia.org/wiki/Johnson%E2%80%93Nyquist_noise https://en.wikipedia.org/wiki/Johnson%E2%80%93Nyquist_noise