Blue and white wire is power antenna trigger.
Please use the solid blue wire for amplifier turn-on.
When you switch to another source other than AM/FM - that signal drops out (and the antenna lowers)
The MP228 does not have a built in crossover or dedicated mono subwoofer out... so you will need a seperate one, either standalone or built into your amplifier to cancel out frequencies above 80Hz.
There are also generic versions called "inline coil"
you wire in the positive line of each subwoofer that will filter out unwanted high frequencies.
(similar to this pic - but without the board... just the coil (top of board))
Harrison Labs make an F-Mod (available in divverent cutoff frequencies) that is installed in the RCA line.
You can try crutchfield.com for both types - and others.
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