What does frequency mean with regard to Broadband?

Question

I read that Broadband is distinguished from Baseband by using a greater range of frequencies in the electromagnetic spectrum and that ADSL divides the 1.1 MHz spectrum into 256 independent channels. However I don't really have a good mental image of what that means. Can anyone assist?

NB: Just to explain currently I'm thinking of it in terms of high or low voltages applied to a line and can't really see where frequencies would enter into it.

Answer 1

If you look at an audio spectrogram you'll see a bunch of different frequencies overlaid on top of each other. Each frequency is a pure sine wave, but they combine to create more complex sounds such as the strum of a guitar, the beat of a drum, or the sound of a voice.

If you compare this with, say, the tone used by a telegraph you'll notice that more information can be encoded since more than one frequency is in use, and each frequency has its own volume which adds to the whole.

Answer 2

They are talking about audio frequencies.

That's the reason you need to insert a filter before your home phones if the ADSL is brought to you with the same line as the phone line.