I know I've seen people say how to do this before and I'm thinking it should be as simple as either feeding the two signals into an op amp (or hell, even just ignoring one of the two signals) but I wanted to confirm with someone else's work before I commit to an answer on this (I would just...

I was wasting time and just throwing parts and values down without really thinking too much about what i was doing and ended up with the below circuit. While i was playing with the value of Co to get a somewhat flat AC response I realised that since I wasn't paying attention to the scale in my...