PREOUT and SPEAKERS filters : type ? [solved: BESSEL filters]

[Waiski]

I have been scratching my head with the crossover... now I finally did measure the crossover and found out that you need to use little mathematics to get it working properly. My friend did help with the calculation.

Order
LP=>-6dB ... -6dB=>HP
HP=>-6dB ... -6dB=>LP
1st 1.733 ... 0.577
2nd 1.000 ... 1.000
3rd 0.765 ... 1.307
4th 0.643 ... 1.556

So for 2nd order crossover you can use this without adjustments. 1000hz is 1000hz crossover point.
But for example 1000hz 1st order crossover point are... low pass is 577hz and high pass is 1733hz.

Handy, isn't it? ...nope