Diamond Amplification MAC-2 - Manual (Page 9)

your MIDI controller needs more than 800mA, an adapter with a higher
current capacity is required.
Power – This unit requires power supply in the range of 9 to 18 volts,
AC or DC. The plug should be a 5.5mm/2.1mm barrel connector,
similar to those used in most effects pedals. The MAC-2 requires a
power supply able to deliver at least 200mA of current. This power is
also passed directly to the MIDI In jack to phantom power the
connected MIDI footswitch. If you are phantom powering, please make
sure that the power supply is sufficient to power both the MAC-2 and
your MIDI footswitch. If you use certain DC power supplies designed
to supply DC power to multiple devices, it may not supply sufficient
current. For example, when using the Voodoo Lab Pedal Power 2, it is
recommended that you use the LINE 6 outputs, which are capable of
providing more current than the other outputs.
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