Do you have the same kind of bass and amp as her? Or a different kind of bass, and no amp? Do you have a teacher? How many lessons have you had so far? Are you imitating/copying bass lines by famous players? I agree with the "you do not need a DI" crowd. Your Scarlett interface is designed for recording instruments like guitars and basses. Purchasing another DI would be like buying a second knife to chop your vegetables into pieces, before you chop the veggies some more with the knife you already own.