[sdiy] Building in a DC offset

[Christopher Mullin]

I am thinking about building an analogue meter like to one shown here:

http://www.angelfire.com/music5/a100/sounds/DIYmodules/NET5COIL.htm

However, I'm thinking about building in a rectified mode and an offset mode. 
  I use ±12V in a Analogue Systems/Doepfer hybrid, so I'm after being able 
to represent ±5V on a range of 0-10V.  I'm happy with building in a 
rectifier, but can anyone show me how to make the offset circuit?

Stuadh