Decimator Design DD-4S (DD4S) 4 x (3G/HD/SD)-SDI to HDMI Converters with Multi-Viewing. The DMON-4S is a truly portable converter, that incorporates our new easy to use LCD and button control system. This gives you easy access to all of the amazing features without using complicated LED/button control, dip switches or having to carry around a computer to change a simple setting. 4 x (3G/HD/SD)-SDI to HDMI Converters with Multi-Viewing