SolidDrive SD-1 Surface Mount Actuator in Titanium The SD1 attaches to drywall and similar surfaces using our patented cantilever spring mounting bracket. Each SD1 is designed for one channel of audio. An optional equalization module optimizes the SD1 for use on drywall. The SolidDrive utilizes patent-pending dual-voice coil technology in an aluminum enclosure to transfer acoustic energy to any substrate with very high-powered neodymium magnets and dual symmetrically opposed motors to convert audio signals into powerful vibrations. Those vibrations are transferred into solid surfaces through direct contact. High-quality, full-range sound is then radiated from the entire surface with a frequency response of 60 Hz to 15 kHz. The symmetrically opposed neodymium magnets and specifically engineered mounting hardware results in hidden planar-source acoustics. The result is acoustical uniformity throughout the listening space. ...