I’ve heard that surround, even if it sounds “louder” to me sitting in my own couch, is easier on the neighbours, because the sound is divided over more speakers, so it is more of a hum to the neighbours, while a stereo speaker emits more sound from one single point, and so is more audible to your neigbours.
True, or am I deluding myself?
And can anyone point me to a site that tells me how to minimize the sound from my speakers to the neighbours? Hard to google for it.
It depends on where your neighbors are, and it depends on the mix of what you’re listening to.
If you share a wall with your neighbors, and the rear speakers are hanging on them, and it’s mixed heavy on the rear speakers, the surround might be more audible than listening to 2 channels.
If the mix heavily uses a discrete subwoofer channel, that might also be louder to your neighbors.
With some mixes, the rear speakers are almost entirely used for pyschoacoustic effects. These will sound louder than a stereo mix at the same volume, but it’s illusory. They won’t bug your neighbors. 
Larry, my neighbours are below me, and my front speakers are on the (bare wooden) floor. All other speakers are hung on inside walls, walls not shared with my neighbours.
So, that means they’re okay, right?
And are there easy things I can do to minimize the sound from the speakers standing on the floor? I’ve heard that isolation and weight serve best to stop vibrations, so what if I put them on a sandwich of foam-concretetile-foam-plywood?
Thanks in advance!
Even something as simple and cheap as styrofoam blocks, foam insulation, or household cleaning sponges (placed under the front speakers) may really help matters for your downstairs neighbors.
In addition, it may make the bass less boomy and cleaner in your own apartment, since speakers placed directly on wooden floors can generate unwanted resonances.
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