Question about sound desing

[kmano]

Hey guys, so first of all I gotta say it's one of my favourites rnb songs over last couple of years. I was trying to creat some sexy sound like this.. but I can't think of any way to make something like this. Im thinkin about this sexy pad/synth sounds that comes on 0:34 and is going throughout the whole song in the backround. What would you do to creat it? It starts as a low synth but goes to be high as it finishes. So it's the frequency thing I guess. Or maybe resonance? Shit, Im really new to sound desing so if you have any idea how could it be made, share your thoughts please

LOL, forgot to post the song!

 

[krushing]

It's just mainly the cutoff opening up and the resonance somewhere halfway up. Probably an envelope opening up the cutoff, but could of course just be automation as well. There's also a hefty amount of reverb, some autopan & the base osc sound which is probably a saw + something else (maybe triangle), plus of course the bassy layer underneath...but the thing you're talking about is relatively simple.