[majgr]

What I noticed is that pitch of buzzing is higher when bee is attacking, not after sting. Higher pitch means probably higher frequency of wings, so bee has more velocity and it is more nimble. When I was kid visiting frequently a place with 100 hives in a summer. I started to recognize that pitch of attacking bee and learned to keep head lower, between arms. Sometimes I was chased by a bee several tens of meters. It is good to use cover of some trees or bushes. I believe bees are aroused by smell of venom itself. Sometimes, when hive is opened, bees turn their abdomen higher, towards opening showing stings. I think I saw that drops of venom forms around end of sting. Smoke particles, probably bonds to venom vapors, neutralizing its influence on other bees, because after couple smoke puffs venom smell is not noticeable any more. Also, smoke causes bees to change their process, from „intruder alert”, to „tree is burning”, and are turning on ventilation. Each summer, first sting swelled the worst, but consecutive ones were less so, so I think some tolerance develops, but it won’t last a year. The worst is being stung in fingertip, because it causes nail deformation, for some time.

[cryptonector]

It's not just ventilation. When they smell smoke they also go eat a bunch of honey so they can swarm away with the queen and start over elsewhere.

[cryptonector]

Oh for sure, they do buzz differently when they are in protec/attac mode.