Subwoofer for Amphion Argon 2 ??

I´m looking for a sub for my small room (10m2).
My room is treated acoustically.
I don´t need spl, only a little more body and extension to the low octave.Argon have a very accurate sound.

So accurate and neutral low end, not punch or combine with my argon 2. They are in nearfield position.