・Behringer Micromix MX400 Ultra Low-Noise 4-Channel Line Mixer - Power Adapter - Adorama 1 Year Limited Warranty. 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 keyboard mix and connect the MX400's output to a single input on your main mixer.
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