My new subwoofer is providing a strange reverberation or "wub-wub" sound on certain portions of deep bass in certain pieces of content. Hoping to see if I can get some advice as to whether its a defect, or whether the base is just too deep for my system to adequately handle.
I've got a not so fancy 5.1 system (Monoprice 5.1 Product #9774, the relabeled version of the Energy Take Classic 5.1 from what I understand). I know it's not a top of the line speaker system, but I thought it would suit my needs in a second room and the last cheapy 5.1 HTIB setup I got (the Harmon Kardon HKTS-15) serviced me fairly well. I'm not an audiophile, but I like a quality sound and the speakers on this system sound great to my ears. The sub on the other hand is giving me issues. This system is hooked up to an Onkyo TX-NR616.
I first hooked it up and let it age with some music/TV for a couple of hours while I was at work. Then I went straight to gaming and played a quick cross-section of some of the games I'm currently playing (Halo 4, Dead Space 3, Assassin's Creed 3) and the sub seemed to handle things quite well. It isn't incredible, but it was good and a step up from the HKTS-15 I had been playing on. It sounded fine with episodes of Walking Dead Season 1 on Blu-ray, including the first episode with the speeding cars and the car wreck near the start.
Then my wife and I went to watch Game of Thrones. Immediately during the opening credits sequence the deep bass of the intro-music started to cause the sub to "wub-wub" along with the music - not all the time, but definitely frequently throughout the intro-music. When my wife notices an audio issue, I know its really prevalent. So I investigated and flip the sub on its side and could see that as the bottom cone was pumping it was producing the reverberation in tandem with the vibration of the cone. The reverberation is really loud, and it was clearly audible over the intro-music coming from the satellite speakers.
The Onkyo 2EQ setup in the room had adjusted the subwoofer to -7 already. I checked the master volume of the sub and found that it was set to 75% so lowered it to 50%. That decreased the reverberating "wub-wub" but didn't eliminate it, and it was still very audible over the rest of the music. I lowered the sub volume to where the reverb was gone (about 25-30%), but then it seemed as it from the normal viewing position you could barely perceive any bass at all, as if it was off almost, so that is not a solution for my preferences. I also played with the low pass filter on the sub itself but it did nothing, probably because this bass tone is so deep already. I have not messed with the crossover settings on the Onkyo except that I ran the 2EQ setup.
Being that it was late and my wife just wanted to watch TV, I set the subwoofer back to about 50-60% and we proceeded to watch. Maybe once throughout the entire episode we noticed the reverb. But as soon as the episode ended and there was a dramatic bass tone and then the end-credits musics we started hearing it again.
We watched all of these Game of Thrones Blu-rays on our older HKTS-15 (in a different room of the house) and never had this issue, even with the sub up pretty high (the HKTS-15 sub is 100W and the Monoprice sub is 200W). When I go home tonight I'm going to try some other content to see how prevalent it is.
Is this just a product of a cheaper subwoofer not being able to reproduce really low bass? If so, why did my older and less powerful HKTS-15 subwoofer not have a problem with it? Or could this be a defect where the cone or something else is too loose and I should call Monoprice for a replacement.
Someone mentioned poly-fill in another thread I was reading, and they said that it seemed to abate much of the issue. I'd be willing to try that. Once I open up the sub, where should the poly-fill go? And how thick of a layer of poly-fill should I use?
Thanks in advance for any help that anyone can provide?