i just got a 606 and have a simple 2 bar loop going. now what i tried to do was copy the loop to another pad and filter the bass and play it along with the original loop but it keeps cutting out the original loop whenever i try to play them at the same time. is there any way to get around this? if not do you have any other suggestions to add basslines? thanks

When you say 'loop' do you mean a looped sample or a sequence you have played/programmed?

If it's a sequence, you are probably running out of voices; the 606 only has 8 voices . You can avoid the problem by simply turning your sequence into a loop first - then it'l take a maximum of two voices from your available 8..