I remember reading in the (brief, lol) install guide, about filters coz of the audio distortion. What features should I be looking for when it comes down to getting rid of any of this.

You won't have to worry about any audio distortion with the mark 2. The Mark 1 has fantastic sound quality, but there is a slight noise floor problem and it's sensitive to ground loops. However, those problems have been fixed in the Mark 2 and it has perfect sound with a very quiet noise floor.

The only distortion you might get is if you put too much sound through a cheap speaker. Fix this by using your amp's input gain adjustment and crossover. You shouldn't need to buy any extra filtering.

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Tony Fabris