our neighbors complained about our bass how can I get it lower?

[DaneilZeitler]

So I have surround sound in my apartment. Our neighbors above us complained about the bass. I turned the bass down already to -6 and it doesn't go lower. How can I defuse the sound so that the bass is less wall shaking intense.
I use it because i've lived in many apartments and no one has complained before. They didn't say kill it but just turn it down. It gives rick deeps for people voices and explosions. I just need to lower it not take it away.
rich*

 

[Destiny]

Lol, why would you have bass speakers in an apartment with many people living nearby? Lol. Just don't use it since people are complaining. Be considerate