Sounds like you're the bad neighbour. If your noise is penetrating her living space, she has every right to be upset. Just because its not "louder than ambient noise if she opened her window" according to the offender means nothing.
Be a better neighbour, FFS. You may not be breaking a bylaw but you're being an annoying neighbour. Subwoofers in an apartment, that'll make you lots of friends in the building!
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