using LADSPA live

[Fran López]

Hello there, i need to do somehing really simple, but have no idea on
wich software to use.
I have to use a LADSPA effect (Feedback Delay Line) live.
That would be simple (i'll just have to jack de audio income to Jack
Rack and load the delay there), but the problem is I need two factors
(the "dry/wet" and the "feedback") to be automatically increasing
(from their min value to their max) over a certain period of time.

Any recommendations?
Thanks in advance,
-Fran López