The VU-DIN can be used as a real time indicator of how close to clipping your amplifier is being driven (when calibrated with the SMD / D’Amore Engineering DD-1 Distortion Detector) and / or as a light show to add a visual sense to your music. Adding a visual sense to your music is great, as long as it is perfectly in sync. With the use of high speed analog circuitry in the VU- DIN, the response is instantaneous. (Hopefully if your system is set up correctly you won’t add the sense of smell, as smelling your music is usually a bad sign)
Owners Manual: VU-DIN