Connecting Subwoofer to the head unit BRZ 2020

[Teppka]

I've ordered an active sub with built in low pass filter. I've also spent some time with my head unit and couldn't find subwoofer control in it. Here is the user manual which I could find online:
https://viewer.joomag.com/subaru-brz...0029201?short&

While there is factory sub for US models (Kicker) which connects with a socket to the head unit, I'm not sure if it's compatible with 2020 head units we have here in Europe. Sub I've ordered is not Subaru OEM one but a spare tire socket type. My question is if anyone has experience getting signal for sub from the head unit? Assuming factory sub (Kicker) can be connected to the head unit, the head unit should have sub out?

I've seen many videos on YouTube where people were getting signal for sub from back left+right speakers or from amplifier in the trunk for door speakers. I was really hoping there is a dedicated sub out from the head unit.

Power on signal is not an issue as it's available from the factory amplifier in the trunk.

Any experience from the members will greatly help.

Thanks.

[soundman98]

you're likely going to need to use the wires from the amplifier in the trunk for the speaker connections. i believe it was only ever the original pioneer units in the early edition scion fr-s models that had rca outputs on the radio for aftermarket speakers. AFAIK, every non-scion model doesn't have rca connections on the radio.