Sony MDRMA100 Over-the-Head Headphones (Discontinued by Manufacturer) Review Posted on April 3, 2018June 25, 2018 by FancyPygmy 40mm driver unit reproduces powerful sound Open-air type headphones can realize wide natural sound field Cord: 2M 40mm driver unit reproduces powerful sound, Open-air type headphones can realize wide natural sound field, Cord: 2M