Hello Head-Fiers,
 
I'm relatively new to all this and have a question:
 
When not using phono/turntables, but only CD/DVD-Players and PC as Audio Source, whats the pre amp for?
 
I get it, that a system can/should look like this (correct me if wrong)
 
Source -> DAC -> AMP (maybe A/V receiver) ->Speakers
or
Source  -> DAC -> headphone AMP -> Headphone
 
so is the preamp between the DAC and the AMP? Wouldn't this cause double amping?
I understand that it was originally used for phono, that is a very quiet medium, and you need to preamp the signal a bit in order to amp it correctly. So in our digital times...whats is it good for?
 
Thanks!

Take a look here:
 
http://www.ecoustics.com/electronics/forum/home-audio/150740.html
 
or here
 
http://www.polkaudio.com/forums/showthread.php?62449-Preamp-vs-Amplifier...Whats-the-difference

So question then is, what is the differeance between my "source" and a pre amp?
Are my Pc and Dac [together] acting as a single preamp unit would? 

Thank You for your answer.
 
So I guess while talking about listening with headphones, a preamp is unnecessary?