I play both acoustic and rock music on an acoustic guitar fitted with K&K piezoelectric transducers. When I plug the acoustic guitar into my electric guitar rig the amp starts howling almost instantly. But when I use a magnetic soundhole pickup on my acoustic guitar there's no howling.
Why is that? Is is just the sensitivity of the transducers to feedback compared with the magnetic pickup?
Is there some way to use transducers as the originating signal for distortion pedals, etc.? Would a compressor-limiter help in producing a strong signal without feedback?