You'll have to learn it by ear...
http://www.youtube.com/watch?v=IQxtCGjLC4I
Or use the simple bass tab... (the simple ones never sound right)
http://www.ttabs.com/tabs.php?id=232128
I have played instruments for a while (bass guitar 2 years, guitar for about 6 years, and violin for about 4 years). Could figure the tunes out, but I'm way too lazy, and I have a lot going on. Really do like Dram's music though.
Searched for Trilltrall.... don't know, this is actually pretty strange.
http://www.youtube.com/watch?v=Gv9cOjNO4Fo