vinodvinu

Hi all, I want to make a mixer circuit with 3 mono dynamic mic inputs and one stereo audio input. This stereo input is coming from either a mobile phone's 3.5mm audio jack or a CD player's headphone out. Do i need three mic pre amps for this 3 dynamic mics ?. If so where do i connect the pre amp ?. before the mixer or after the mixer?. Please suggest me some good circuits.