Am I doing this right? New User

I recently lost my 5.1 surround sound logitech speakers from twenty years ago and I am now trying to set up a simple 2.1 system for gaming and music from my computer. This is my equipment:

Edifier r1280dbs

Monoprice 8 inch 60 watt sub

Creative X3 (Got because my 5.1 Logitech supported DTS and DDL decoding via optical)

I have the Edifiers connected to my X3 via optical and the sub connected to the edifiers via the sub out. The X3 has a 2.1 setting which lists bass redirection and bass gain and a crossover slider. The subwoofer itself has a subwoofer crossover that goes from 50-150hz. The edifiers are listed at 51hz- 20kz. I have to turn the crossover on the sub all the way to 150hz to even notice its there. Anyone know what I should be setting this stuff to? I tried activating the bass redirection and subwoofer gain on the X3 but it sounds better without it, I think it maybe due to the edifier automatically sending the bass to the subwoofer through the subout port.

Thanks from a audiophile newbie.

Sorry to hear about it. How did you lose it?

Just would not power on. It gave me twenty years of service. I think it shorted out due to a thunderstorm we had.