reply to desarollo
Re: HOW??? Exactly. It's all about relativism, as the absolute level is irrelevant, as one person might have a small TV in a small room, while another might be using a beefy 7.1 surround receiver in a large room that is pushing a lot of power out for a similar volume level at the user's ear.
This article is pretty pointless, since TiVo has been doing this for about a decade.