+1 on NOT rejecting your brother's advice just because he's a "guitard" (what, there aren't any stupid bassists?

) or just because he's your brother. Your sound might be perceived as louder right now and thats how he chose to articulate it...whether that means you need to EQ your sound or just simply turn down the volume a notch, or do nothing...something's bugging him...ask him to point out a recording that he considers as "great bass tone".
Nobody asked so i'll just do it: What songs/style do you two play normally? the style of the music and the blend of all the instruments is more important than individual tone...record both of you playing together then we can give a more informed opinion. There's too many variables to make a call on this (and as someone else said, unless that recording is from a mic in front of your amp, we don't know what you REALLY sound like in the room).
All that said...I think worrying about your tone is secondary as a beginner IMO of course; it comes after making sure your groove is solid and unshakable...don't know if you weren't focusing, but your time was all over the place on that clip. Not trying to be 'that guy', but just trying to put things in perspective. Brothers will annoy you, that's a given, just make sure you work on your groove and technique...great tone will come if those 2 are solid...and great tone (like great music) is HIGHLY subjective anyways.