Optical cartridge systems offer an added benefit: since they only detect changes in brightness (what DS Audio calls “shadow movement”), they effectively eliminate any form of magnetic resistance when the vibration system moves. Since there is no magnetic resistance applied to the vibration system (meaning the tip of the stylus and the cantilever), the tip of the needle moves smoothly as it traces the LP grooves, exhuming, at least in principle, more information from your favorite discs. Additionally, the low-mass light-shielding plate, when coupled to a stylus/cantilever assembly unencumbered by any form of magnetic field resistance, should ideally translate to lower noise and superior transient response fidelity.