I have the timefactor, and have a swelling preset as well. I use my volume control with my swell though, so I control the swelling rate with my actual volume knob. The preset Does Not automatically swell however. If this is what you were looking for, I do not believe the timefactor can do this alone. You might try to set the mix to 100% wet though. You might be able to dial in a sound you like with this method.