The VPI Analog Drive System, or ADS, ensures your turntable runs with rock-solid speed stability. It's also a high-tech speed-selection device for 33 1/3 and 45RPM. Free of digitally based electronics, the extraordinary-sounding ADS represents an evolution of the function embodied by VPI's SDS (Synchronous Drive System) and an entirely original way at looking at the speed controller concept. Audibly superior to SDS, ADS represents VPI's biggest non-turntable breakthrough in the 21st century and brings bold, across-the-board enhancements to the performance of almost any turntable. If your ‘table uses an AC Synchronous motor that draws less than 10 watts, you owe it to yourself – and your analog setup and vinyl – to audition this new motor controller. Simply plug your rig into ADS and hear the improvements a truly powerful motor drive creates: Deeper bass, smoother midrange, sweeter highs, lower noise floor, deeper imaging, airier top end, and reach-out-and-touch-it solidity.