ah, ok. cool.I think I was the one who posted the link some time ago
@tcguy85 - your soundcard must have a line in (aka microphone symbol) and a line out (aka the headphone symbol).
Both are stereo although you only need the left channel for the calibration. This is not affecting, at all, how you should proceed
1) You need a cable with two 3.5mm jacks (one at each end).
2) plug one jack in the line out
3) plug the other jack in the line in
4) set the sound level as described in the link posted
5) run the calibration
You are done.