I honestly never tried to run mine at 400hz x-overs (mainly since CDT recommend 500hz x-overs). However, I did help another member tune his as well and he had them crossed over at 400hz acoustically - and he was VERY happy with the results.
Honestly, I doubt that it makes that much difference between 400hz and 500hz. I would just use 500hz to be safe.
I've never heard any bit of distortion from the Unitys - regardless of volume level. But then again, I don't listen at 100dB either - and never will. I love loud music, but my system honestly gets louder than I can use - with only 6x75W RMS + sub amps. I truly don't understand the need for tons of power - unless you are concerned with what people OUTSIDE the car hear. My windows are ALWAYS up and I just want music loud enough for ME in my car - and it easily handles that!
Time alignment was straight forward (distance measurements) - except for the two subs (one underseat and one trunk sub). I had to get "creative" with the timing to get both subs and the midbass to all play nice together - but it works well when done.
Honestly, I doubt that it makes that much difference between 400hz and 500hz. I would just use 500hz to be safe.
I've never heard any bit of distortion from the Unitys - regardless of volume level. But then again, I don't listen at 100dB either - and never will. I love loud music, but my system honestly gets louder than I can use - with only 6x75W RMS + sub amps. I truly don't understand the need for tons of power - unless you are concerned with what people OUTSIDE the car hear. My windows are ALWAYS up and I just want music loud enough for ME in my car - and it easily handles that!
Time alignment was straight forward (distance measurements) - except for the two subs (one underseat and one trunk sub). I had to get "creative" with the timing to get both subs and the midbass to all play nice together - but it works well when done.