Atmosphere has some great sounding pads. The new Ultra Focus (not yet released) will have some nice ones and I hear Morphology is quite nice. These are all sample based but it doesn't mean you can't sculpt them to fit the context of your song.

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Albino is kinda good for pads..

I use it in combination with atmosphere.

mm i think he was talkin about the process to make those sounds.
i would like to know more too...
what i know is that sine, like u said, is the best way. saws will give too much harmonics. Sine and maybe some square. Also, thin frequency range, eq it to hell. reverb it to hell to, maybe cuting the dry signal to make it more dreamy and hollow.
Stereo enhancing is a must to take it out of the center and make it more ambient.
Flanging, phasing and lfos can help too.

Atmosphere and albino is what i use

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Well i know bout atmosphere, but albino too?
Thats new to me, i usually makes trancy sounds with it, never tried this kind of stuff.
Do u hav some interesting atmospheric pads patchs for Albino?
I would like to study how they are synthesized a bit more deeply (since atmosphere is sample-based)

Btw i just remember
Angelina is nice too (ty Cyrus2k for the tip ^^)
Its usually used more for choirs, but it can make some ambient/trippy/atmospheric sounds very well