Hercules DJCONTROL INPULSE T7 Manual De Instrucciones página 74

We do not recommend that you connect two pairs of
headphones at the same time (i.e. one to the 1/8" / 3.5
mm mini-jack output connector, and one to the ¼" / 6.35
mm jack output connector). If both pairs of headphones
do not have the same impedance, they will have
different output volumes.
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