Quantum Audio QP4250 - QP4250 - QP4400 manual pg 3 & 4

Low Impedance Stability
QP4250 - 2 Ohm Stereo (4 Channel)
QP4400 - 2 Ohm Stereo (4 Channel)
The Quantum QP4250 and QP4400 are equipped with a built in variable crossover
network allowing you to select the crossover function and frequency for each the front
channels or rear channels of the amplfier independently.
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