O
If you want to deaden it, build a double stud wall staggered and weave
fiberglass insulation between. Used it in an college athletic dorm and
it works great! But merely empty space is NOT a sound barrier.

even better to build two walls that don't touch.
yes I do know about it I did a fair amount of study about it when i was a
recording engineer.
dead air is very effective but it has to be done right. it takes more then one
layer. but sound will not penetrate very may layers of material if they can't
interact with each other with anything other then air.
so yes one hollow all will not do anything but two will do great or layers of
insulation that does not touch each other will work great too. it's the
separation between them the dead air space between them that does the job.


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