Haun OSS Schneider Disk, sound-absorbing disk placed between two microphones to create an acoustic shadow between two omni-directional microphones in OSS Technique (Optimum Stereo Signal), original size (30 cm diameter, 16,5 cm distance), especially used for symphonic orchestras, choir, brass-bands and chamber music, same as Jecklin Dis but with better Stereo width in high frequency range