Noise is measured by decibels.
- Near total silence - 0 dB
- A whisper - 15 dB
- Normal conversation - 60 dB
- A lawnmower - 90 dB
- A car horn - 110 dB
- A rock concert or a jet engine - 120 dB
- A gunshot or firecracker - 140 dB
So, shouting is around 85 dB. If you are at an affair and you have to shout to be heard by the person beside you, the noise is 90 dB if you can understand each others' shoutings. If you cannot hear each other the level is over 100 dB and you are entering a range which may seriously damage your hearing! Get out of there!
P.S. Music at a social function (or any other type of noise for that matter) should not be habitually higher than normal conversation, so people can talk! Otherwise it is not a social function but the interaction is reduced to a subhuman level: i.e. no intelligent communication (except perhaps by texting!). Intelligent communication takes place primarily in the exchange of conversation.
Seek silence: blaring noise is one of the enemies of peace!