[sdiy] cv scaler

[Mountain Man]

For my next mini-project, I want to build a circuit that will let me
either amplify or attenuate any control voltage (up to audio
frequencies), and be able to add a plus or minus offset.  I'm
envisioning something with two pots - a scale and an offset - both with
center detents.  With both in the center position, the signal would pass
unchanged.  Does anyone have a circuit like this, or could someone give
a beginner enough hints to "build from scratch"?  :)

Thanks much,
Elby