for people that build boxes

if a box is built for 50hz.  what exactly does this mean?

It means that the peak output of the sub will be centered around 50Hz.  The design of the enclosure and the sub in it will determine how sharply response falls off from that peak frequency.

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Kevin Pierson

set to low pass on a mono amp.  my question is setting the low pass filter to say 125hz means that it will play tones UNDER that frequency? (is the assumption that high pass is disabled since its set to low pass)

Also how do the high pass and low pass filters affect the speaker when set to Full range?

That really has nothing to do with how the box was built but you are right on.

If your sub crossover is set to 125hz it will only send frequencies below that to the sub.  In full range mode it sends all signals to the sub.  There should also be a crossover slope that will tell you how steeply the crossover cuts off frequencies outside of the range (it isn't an immeidate cut in most cases, more of a fade)

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Kevin Pierson

Have gotten away from car audio recently and needed some answers in lehmans terns. Lol

Thanks again man