If there is no line-in on your sound card just make a mono jack and plug the headphone amp into your mic port.
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If your amp has a headphone jack then you should run a line to the line-in on your sound card. I got a rockman and just run it on clean sound and use my effects through it rather than my amp when I record on the computer and ran the headphone line into my sound card.
If there is no line-in on your sound card just make a mono jack and plug the headphone amp into your mic port.
If there is no line-in on your sound card just make a mono jack and plug the headphone amp into your mic port.