Unsure if I should buy a new surround system

[DanH12]

Currently I have a Sony STR-DE845 receiver, JBL sat10 speakers and a JBL bass16 subwoofer. I am not that happy with the sound I am getting from this system as it is just okay. I definitely need a more powerful subwoofer for my 11 x 18ft room that it is in for starters. The dialogue always sounds distorted on my center speaker so I think there is something wrong with it. I have swapped one of my front speakers with the center speaker before and voices don't sound distorted when using my front speaker as a center speaker. To somewhat fix this I am using one of my front speakers as a center speaker, I then used a rear speaker to take the place of that front speaker and my center speaker is now where the rear speaker was. This sort of works but still sounds a little off.

I have a few other options. I could try to buy a used single JBL sat10 speaker off ebay and I could also buy speaker stands as my front speakers need to be farther apart and my rears need to be at the same height. Only speaker stands could resolve that as I can't drill holes for wall mounts in my basement. Also, I could just buy a new and more powerful subwoofer. My current subwoofer does not produce much bass and has no subwoofer input jack so it is connected to the receiver with speaker wire which is less than ideal. If I had a subwoofer properly connected to my receiver using the subwoofer jack I imagine it would sound a lot better.

Should I try the options I mentioned first or just get new surround speakers?

 

[LB06]

How exactly have you connected the sub to the receiver? You say with speaker wire, but your receiver doesn't seem to have high-level subwoofer outputs. Are you sure you've not connected a low-level output on your receiver to a high-level input on your subwoofer? Then it's not at all surprising that the subwoofer doesn't produce much sound at all. Or have you used the B fronts outputs to connect the sub? That could work, as long as you set those speakers to large in your receiver.

But according to Google Images your sub does have line-level inputs so just use those and connected to the line-level subwoofer output on the receiver. Then you'll also be able to apply a crossover filter properly.

 

[DanH12]

The subwoofer has no subwoofer input jack/low level input on it. I know you have looked at google images but I have checked my entire subwoofer many times over and there is not one. My receiver does have a subwoofer out jack but that does not matter since the subwoofer does not have a subwoofer in jack. So what I have done is connect the front left and right speaker (A) outputs on the receiver to the front left and right speaker input terminals on the subwoofer. I then connected my front left and right speakers to the front (B) terminals on the receiver. This sounds the best for me. I also tried connected the front left and right speakers to the left and right speaker output terminals on the subwoofer (which several others in other forums have recommended that I do) but that always makes the dialogue sound muffled in movies. I still get roughly the same amount of bass connecting the front left and right speakers to the receiver instead of the subwoofer. The front speakers have always been set to large and the center and rear speakers have been set to small and to only output frequencies greater than 120Hz. The gain on the subwoofer has always been turned up to max and the subwoofer has no crossover knob, only a gain knob. On the receiver, the subwoofer is set to "no" because the subwoofer is connected through the front speaker terminals on the receiver and setting it to yes would only work if the sub was connected via a subwoofer in/out jack from sub to receiver. Lastly, I did the sub crawl and I have placed the subwoofer in the spot where the bass sounds the best.