Wow, all those years of reading Japlish in Sony Broadcast equipment manuals hasn't prepared me for Russlish. C'mon, was that really how you were going to design it? I was thinking along the lines of a single supply jfet op-amp with a zener bleeder supply and a bipolar series pass. Just a protected voltage divider input and reference scheme. Should we have just considered the ye ol' LM723 ?