Hi everyone, I been trying to modify a headphone amplifier that I have to make it better for my specific headphone response. The thing is that I am using multisim software to test before actually making the physical changes, the problem is that I don't know what tool to use to see if my circuit is actually amplifying or making any change. As the input I am using a function generator with 1khz and 10V of amplitude, but in the output I don't quite know if I need to use the oscilloscope, or any other specific tool to graph the changes. I did try to use the oscilloscope, in a schematic I found in a headphone forum, and I didn’t know what the amplification was, since I was giving a sine wave as input, and the output which came from an opamp was a square wave, so I got kind of confused. So that’s why I am asking. Thank you in advance for any help.