DS Audio is a division of Digital Stream Corporation, a front runner in the laser optics market for the over 25 years and co-developer of the optical mouse with Microsoft. Using their expertise in optics combined with modern technology, their engineers have perfected the optical phono cartridge, using light to create the musical signal. Immersed in the high-end audio space, DS Audio offers a complete line of optical phono cartridges and matching phono stages. All DS Audio products can be mixed and matched giving the listener the ultimate in flexibility and a true upgrade path.
Traditional Moving Magnet and Moving Coil phono cartridges use electromagnetic generators. For an MC cartridge, the stylus/cantilever moves a coil of wire within a magnetic field and is superior to an MM cartridge due to its lower moving mass. An MC cartridge has to combine coil design, magnet strength, and generator characteristics to create real-world output without distortion and overload. Resistive loading of the MC cartridge helps adjust its performance both mechanically and electrically.
Moving Magnet and Moving Coil cartridges belong to the “velocity proportional” method where the output signal depends on how fast a magnet or coil moves within the magnetic field. At lower frequencies, it moves slowly in the magnetic field, so the output signal is very weak. Conversely, at high frequencies, it moves faster, so the output signal becomes disproportionately strong. A phono preamp requires complex circuitry to compensate and correct velocity proportional output signals in addition to RIAA equalization.
The optical cartridge belongs to the “amplitude proportional” method where the output signal depends on how much distance the stylus is moved, and is not frequency dependent. As such, it only requires a very simple, high quality circuit and uses passive RIAA equalization.