How to listen to music, and play a Minecraft without lag (Chrome/ PC)?

I like to listen to music, and play Minecraft. But when I do, I lag. And I have Minecraft on the lowest settings, plus the song, and it still lags. And I use Youtube. Or Grooveshark. But sadly Grooveshark is dead, so just Youtube now.

If your using a mac, close out everything, but the game your playing and youtube. If still lag, if you have some sort of smart phone, listen to music off of that.