Mas is a great song, but whoever wrote the bass part got lazy, 'cause it only has four notes in it. I feel like I'm cheating by even calling this a tab, but here it is. G:--------6---------6: D:----6-9-------6-9--: A:--4-------4-4------: E:-------------------: The same baseline can also be played with this fingering: G:----1-4-6-----1-4-6--: D:---------------------: A:--4-------4-4--------: E:---------------------: Or: G:--------6---------6--: D:----6-9-------6-9----: A:---------------------: E:--9-------9-9--------: I'm not sure which is easier. The bass just repeats this pattern through the whole song. There are a few measures when it rests, listen to the cd for those parts and to get the rhythm down. I found the fingering for this a little awkward at first, but it just takes repitition to get it down, and it's really easy after that. Maybe it would be better if it were in a different tuning, but I kept mine at the standard GDAE. Have fun!