I see, that does explain why my 660S work great with the Mac out of the box

>But assuming the source of your static is caused by your motherboard's
headphone jack running out of steam at high volumes, then yes, it should
be rectified by adding an external amp alone.

Noted! In that case I'll start looking into some decent AMPs with those and other recommendations and seeing how it improves it before getting a DAC, thank you for the clarification c: