It was Alpines intention for the M250 amp to match up with the bassline series suboofers.

Just remember to set your gain with a multimeter if possible, using ohms law.

the square root of rms watts times ohms resistance or in the case of your potential set up,

250w x 4ohms = 1000 the square root of that is 31.6 that is the AC voltage you want to see coming from the speaker outputs at full volume.

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