Re: Intro and of course questions
There are pre-made systems that they sell around Christmas time, that only have 4-6 channels, and they do a pretty good show. They don't have the ability to change the music like you would building something from here, but it is a good show otherwise. So 24 Channels would be plenty for your first year.
In addition to what everyone else said, I simply think of a channel as an outlet, since most of us will hook up either a traditional outlet or a female end of an extension cord to out hardware anyway. You will have the ability to control on, off, and dimming to each of the outlet, but that it is. You can't do anything fancy like make a multi-color string of lights chase itself if it is plugged into one outlet... just like you couldn't do that with a normal outlet. You would need 4 outlet, and 4 different color light strings to make that work.
1 channel, 0 dimmable. Powered by a man flicking a lightswitch to the beat.