in installs i've done in the past i've usually set them between half and 3/4 power. i don't do them at full power. it's just converting your high level back to a low level and then you can use the controlls on the amp to fine tune it. just make sure both sides are set the same.
2013 F150 4x4 SCrew XLT 5.0L
Midwest Crew #22
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