please help for crossover setup on CB3, Butterworth/Linkwitz/Phase Perfect
please help me to choose a right crossover type.

thanks in advance
Right for what?
In het manuel Theta says that Phase Perfect is the best sounding crossover


Since such choices depend on the rest of your equipment and your setup, there is no best for all cases. That's why Theta offers options.

When choosing the "best" crossover, this will depend on the tonal balance/response of your system. Phase perfect (rolled off @ the same as linkwitz) will have a boomier sound. I prefer the Linkwitz rolled off @ 40/12 db. Butterworth is so versatile you can "play" with the roll offs/db's on both high & low frequencies. Still for my system (Krell amps, Wilson speakers with Bag-End sub) I like Linkwitz/Riley.
I was going through my "Threads" and came upon yours. I have since purchased a Kora Hermes II DAC. Since then I'm running "Analog Direct Matrix." The sound is so much clearer and the volume is several db higher. This way, you can still use the sub output on the Theta. I only use it for 2-channel and turn the rear speaker off. My CD player has a variable output and sometimes for "fill", I use it into an alternate amp to control my rear speakers. If you get a chance to run an outboard DAC, try this-you'll be impressed. Or if your CD player has an analog out, use the analog direct anyway.
Handymann... You’re absolutely right about the Analog Direct and Analog Direct Matrix modes. I have a Casablanca II with an Extreme dac, and a Theta Compli cdp. My Compli’s digital out is connected to the Extreme dac with an XLR Kubala-Sosna Emotion digital interconnect, and the Compli’s analog outs are connected with Kubala-Sosna Expression single ended interconnects.

IMHO, the Analog Direct Matrix mode beats the Extreme dac’s Stereo mode hands down.