Whispers of a working chip, page-169

Any restriction will increase the pressure the air is released at like putting a sprinkler on the end of a hose and the same would happen in reverse creating a vacuum pulling air back in.
Given that the chips are built as a mirror image the opposite effect is happening on the other side every cycle I believe this is what they were referring to in 2015 recycling acoustic elements and transferring the effects from the other side to the wave front.
I am definitely not skilled in the art but would be interested to hear what the skilled people think this is how I have always believed it worked.