The mic shields prevent "p" popping, or help anyway. The first few recordings I made with Margaret Nelson, we were recorded by sometime MC contributor Paul Stamler. He made shields by cutting up panty hose, so we dubbed those crotch filters. I found I could avoid the p popping by singing over the mic, not into it. More recently mic filters are still in evidence, though I don't think they're made with cut up panty hose anymore.