Can I stream music to a hifi through Apple TV

I am planning an extension at home and I would like to set up a multi room music system and use Apple TV to stream music from ITunes. The first query is that both myself and my wife have separate iTunes accounts with our own music on each, can I set up home sharing on both accounts using just the single Apple TV?

My next question is can I stream the music to an amplifier from Apple TV? I've heard of DAC but I'm unsure as to what it is, will I need this to link to a standard amplifier? I plan to have ceiling speakers in my kitchen extension which will be powered by the amp.

In the other rooms I will use Bose speakers with a wireless link, which again I assume will be found with ATV?

Can anyone help me.

Many thanks

Chris