Help needed with passive filter calculations

[zavas]

Hello. I have been passionate audio lover since early age. I used to build some speakers, unfortunately, most of design went into choosing drivers and modeling the box. My last speakers, almost 15 years old at his point, with Peerless SDS 164 and Visaton DT94 is my daily drivers for all this years. I did not had much of experience with crossover design, so went easiest route. First order filters. I have decided to upgrade filters, but would like to get some help. I did not managed to calculate notch filter for woofer. I would like to have 2'nd order crossovers and smooth response. I am considering to lover crossover point to ~2kHz.

Current filters and simulated response
Listening position response
1 meter response, not gated
1 meter response gated

Baffle layout:

Front: 101,5x20 cm (40x7,9 in)
Tweeter center 7,5 cm from the top (3in)
Mid-bass 22cm from the top (8,5in)
Port size, 8cm wide, 11,5cm long 12,5cm from bottom (3,14in x 4,5in, 5in from bottom)

Internal volume 27 liters 0,95 cubic feet

 

[zavas]

I was trying to make some calculations for 2'nd order filter. As starting point I have used online calculators and Vituix CAD software.

I have used this example. It should be Linkwitz riley, but using this tool it shows as Chebychev alignment, so I am little bit confused. On other hand simulation looks quite good. Could someone suggest solution how to filter out woofer's 5khz peak? What is "normal" workflow designing filters?