Behringer micromix mx400 mixer behringer mx400 p the behringer micromix mx400 is the mixer equivalent of a pocket battleship p p this 4 channel line mixer yields the highest sonic quality at all output levels boasting the same op amps found in its much bigger brethren p p if you are running short on available channels on your big mixer and need to bring the output of three different keyboards into your mix you can simply connect them to the mx400 work out the keyboar