| Yeah, I don't think TB search results work as links for some reason. But you could link directly to a couple threads.
I have a passing knowledge of Imogen Heap but I'm not that familiar with all her stuff. From what I've heard the synths seemed pretty delicate. Not over the top like you'd find in jungle, right?
That could prove a bit difficult. There are dedicated synth pedals for bass (EHX Bass Microsynth, Chunk Octavius Squeezer, Boss SYB-3 & 5, and the discontinued Korg G5 and Akai Deep Impact) and you can simulate some synth sounds with an octaver/fuzz/filter setup, but those sounds are generally pretty lacking in subtlety.
Maybe if you gave us a link to a video or clip of the sounds you're looking for we could suggest something appropriate. | 
