I would suggest, as I said earlier, get a new receiver and try it out against the Sony. I did notice a difference going to a Denon from a Sony. I would also suggest you get an SPL Meter so you can properly calibrate the system, this helps immensely with sound stage and blending etc. especially with your sub. Don't worry about not knowing how to use it, we can help you out, it really isn't hard, use your test tones and adjust each speaker/sub so they all read the same on the meter at your main listening position. I would then suggest a new sub, the newer subs reach lower and offer more power for better HT rumble
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