I am starting to think I do have a problem with the Sherwood R772. It has 2 sub modes, normal and subwoofer Plus. It has been at sub plus the whole time because when I put it to normal the sub doesnt work at all. It did the same thing with the EP175.
I think all this discussion of room size and bass cancellation is a wild goose chase. You have set up an 80Hz crossover on your front speakers (small) and your sub only works (somewhat) when you set the Sherwood to subwoofer plus but not in normal mode. You are connecting your OPPO to your Sherwood with HDMI.
I believe that narrows the problem down quite a bit. Keep in mind that you may have other things such as placement, etc that can be improved; but
you are not getting normal LFE information out of the Sherwood at a level that your sub can make use of. It could be defective equipment,
but it is much more likely to be a setup problem with your combination of OPPO and Sherwood.You have been given great a idea of hooking up directly from your OPPO to your subwoofer using an RCA cable. This will confirm if your sub is OK. I don't think you have tried that or at least reported the results.
Go back and read Clubneons post again. If you will try that and let us know the result if will be an additional confirmation; and we can be more helpful to you in troubleshooting.
