We have lots of hives very close to rooftop powered vent and A/C gear here
in the City.
While some of this equipment can be noisy enough to dive the beekeeper to
distraction, it does not seem to bother the bees in the least.
The noise is irregular from all but the most massive systems.
The vibration is pretty easy to see, small ripples are produced in water
bottles that are set down on the roof.

A/C units produce waste water, which often simply drips onto the roof, so
the bees like these reliable and gentle sources of water, often more than
the water source provided by the beekeeper (as required by the local health
code).

I would have thought that an irregular source of vibration would upset the
bees, but I've not seen it.

In contrast, I was emailed an anecdote by a person who was convinced that
the ringing of a local church bell was causing his bees to quickly exit the
hive and become highly defensive.  I suggested he might requeen.  What else
could I suggest?

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