Honestly, it is hard to tell from the photo and description exactly what that wall plate is. What is the connector on the inside wall side and the outside wall side? It would probably work provided you terminated your cable with the requisite end that works with the inside of that wall plate and provided the cable you wanted to use to connect your subwoofer had the correct ends to work with that wall plate and your subwoofer.
No. Not by itself it won't.
Is that cable in your initial photo in-wall or is it already coming from a finished wall plate?
The adapter in this particular link is made to go on an F type male coax cable end that is already attached to your cable. Your cable is not terminated. The adapter in this particular link will not simply attach to your cable, now. You can attach an F type male end or you can attach a compression RCA end depending upon exactly what you want to do with the end of that cable. Both (F type or a compression RCA) would require special tools. If you attach an F type male end to that cable, then the adapter you linked will screw onto it.
You have several options, though, and we would need to know more to help you decide exactly what to put on the end of it.
These are F type male ends for you cable. They can be twisted on if the cable is properly stripped and prepared prior to that.
There are wall plates that have a female F type connector on the inside wall side and a female RCA on the outside wall side. And there are wall plates that have female RCA connectors on both the inside wall and outside wall side. Both would work for you depending upon how you decided to terminate that cable. You could even use a wall plate that has F type connector on the inside wall side and an F type connector on the outside wall side if you wanted to make your own subwoofer cable from another piece of coax.
You have a lot of options.Edited by sivadselim - 5/6/13 at 4:53pm