You can record without a headset. But it's a bad idea. So many little things are picked up that you can't hear with your weakling human ears. Something as tiny as a small tap on the side of the boom will sound like a loud "crack" in your recording. There's also that siren in the distance that's so subtle that you don't notice it with your ears, but it's going to make editing a major biatch. Get a good headset.