Vandersteen 2W sub connection

Vandersteen has a manual you can download on their web site (I know you mentioned you have a manual, but make sure it is the correct one). Do you also have the WX-2 crossover box? Not sure you need that for the 2W, But do believe you need it for the 2Wq, and the diagram on your photo shows the WX-2 in the path.

Basically Vandersteen does not design his 2Wq subs with LFE connections, so you have to connect them from your amp speaker terminals with the WX-2 in the path as shown. The set-up is probably the same as the 2Wq manual on their site.

I’ve never used them, but that may be a good place to start.

NOTE: Vandersteen also has a manual for the V2W, which does connect via LFE, and that may be what you have, and what that red middle RCA connector is for, but it’s manual states it has two RCA jacks, your photo has one. If you do that, simply disregard the other speaker jacks, just as you might on many other powered subs. Again, if that is what you have, look for that manual instead of the 2Wq I mentioned. BUT, again, your photo does show the diagram with the WX-2, so figure out what you have, or perhaps someone will jump in who has used these. Given the diagram shows the WX-2, I think you have a 2Wq (?).

I’m sure Johnny @audioconnection could help you out.

It does come with a WX2 crossover. Doesn't say "2Wq" on the back, just "2w". Does the red plug look like an RCA? Looks like another banana plug to me. 
https://photos.app.goo.gl/uZ2pS7LDrGshRppY7

Yes, perhaps an older model before the ‘q’ came out. As You have the WX-2, with the dip switches (internal) to be set per the impedance of your amp, I’m guessing the set-up is like the 2Wq. Also, make sure your WX-2 does indeed have the internal dip switches, and not a set unit for a particular/set impedance level. Most will tell you that the WX-2 should only be used to temporarily set-up the sub to your particular amp, then better to buy an X2 with the fixed setting you need for the best sound.

Try contacting Johnny Rutan here : @audioconnections. He knows all about these and will get you set-up. Or call him at Audio Connections in New Jersey.

Setup for the 2W and 2WQ is identical. If you have the manual you need to read it completely before starting.