AVC4 Level Controller Signal Attenuator 4Ch (2x Stereo Chan) 1UThe AVC 4 Automatic Volume Control is an analogue, stereo automatic volume controller, which means the dynamics of the sound remain the same, whereas compressors alter the sound. The AVC 4 is 2 AVC2s in a single 1ru case. Increasingly it is a condition of licensing that sound levels in a venue are controlled to a specified maximum level, the AVC 4 will perform this task. The AVC 4 will control the level of 2 stereo channels to a maximum set level