The M-633D is a stereo mixer equipped with 12 input channels (6 monaural inputs and 3 stereo inputs) and 6 output channels (2 monaural outputs, 1 stereo output, and 1 stereo recording output). It has 2 monaural channel and 1 stereo channel bus lines, allowing each input signal to be assigned to each bus line individually. It features digital signal processing functions such as Automatic Resonance Control function (ARC), Feedback Suppressor function (FBS), Automatic Clipguard function (ACG), and Automatic Mute function (AUTO MUTE). It performs advanced acoustic compensation by means of automatic processing without the use of an acoustic measuring instrument. It can be mounted in an EIA component rack (1U size).