Tony's right. The best way to do that today is to assign PINs, like 7, 8, and 9 to three sounds you want access to. It's 3 total button presses to play the effect, but that's still pretty close...
Just make sure you make the tracks, or the playlist they're in "Ignore as child", or else they'll get shuffled into your play orders, which could be disconcerting if you're not expecting it.