The Sonic Foundry Noise Reduction DirectX Audio Plug-In is a collection of four essential plug-in tools: Noise Reduction, Click and Crackle Reduction, Vinyl Restoration, and Clipped Peak Restoration.

The Noise Reduction tool analyzes and then removes background noise such as tape hiss, electrical hum, and machinery rumble. Unlike average filters, Noise Reduction cleans up audio without removing any of the original source material. By creating a 'noise print,' Noise Reduction stores frequency and amplitude information about the background noise in the recording to determine which frequencies to remove.

The Click and Crackle Removal tool detects clicks and pops, often found in older recordings or as the result of bad splice editing, and automatically replaces them to minimize their audibility. Click and Crackle Removal offers enhanced isolation and removal of crackle noise—clicks and pops that occur in rapid succession.

Use the Vinyl Restoration tool to restore the audio quality to your vinyl collection. In a single operation, Vinyl Restoration first removes the pops and clicks generated by dirt and scratches in the surface of a record, and then removes the broadband surface noise from the old recording.

Salvage that once-in-a-lifetime recording you thought you lost to clipping using the new Clipped Peak Restoration tool. Clipped Peak Restoration recovers the lost clipped signal and reduces the harsh distortion that results. The tool 'rounds' the tops of clipped peaks and applies peak limiting to the area immediately surrounding the audio clip.