If I get the DT770s, and want to get an amp with it, cause they’re 250ohms, and then run it out of my goXLR mini and I’ll be using them with my PC, will I need to power the amp directly from my PC for me to get any audio from my PC? Or can I power it just from my power bar, and run the headphones through the goXLR mini and still get audio from my PC?