http://soundcloud.com/snbrn/dirty-south-unbreakable-snbrn-remix-official

The lead bass noise starts at 1:32. I've heard it in a few songs, so I feel like it's a preset. Any ideas?

 

Korg M1 organ, it's a straight preset from the synth. Classic sound used on countless UK Garage/House tunes. In this track it sounds like it's layered with another sound though.

Another example:

http://www.youtube.com/watch?v=M47OF64YyHY

I actually think I have a multi sample of the sound somewhere in my sample library, If I find it I can upload if you like?

 

hi here are three presets for Sylenth1
if they dont sound right when you load them in mess around with all four oscillor waves.
four waves are set to pulse in one preset and the others have two pulses and two triangles.

if you can,get these Videos Tutorial / Dance Music Production - Synthesis one and two
they will help you out all the best.

http://www78.zippyshare.com/v/50032539/file.html