Just bought my son a bass on ebay for Christmas (he's hanging up his drumsticks). He wants to do most of his practicing with headphones thru his MAC. I know he needs some kind of interface, but beyond that I'm lost. Aside from just needing to hear his bass thru the computer, he would also like the capability to play along with audio file (youtube, backing tracks, spodify etc.). Also any of these devices have effects capabilities (overdrive, compressor etc). Any suggestions? Makes? Models? Appreciate any help. Thanks