I suspect my experiences bartending lead me to having the problem GP describes. Too much noise over and over... (although the summer jobs working with machinery and not enough ear protection and all the concerts probably contribute too).

But during bartending a few things are true:

* it's not too loud when you have time for a conversation.

* if it is too loud to converse, you're probably busy enough that interaction very simplified to a small subset of language - so lip reading becomes a big contributor to understanding. (e.g. basic greeting scripts, "can i get a..." and so on)

* when it's loud, it's pretty socially acceptable for the bartender to lean in to the conversation to hear - the "personal space bubble" of the speaker tends to shrink in that instance. Similarly a bartender asking you to repeat that a bit louder isn't considered rude.

edit: I wish I was clever enough to say this in as few words as BurningFrog did :)

The bartender API is very limited. The customer is either ordering one of a few enumerated things, or asking one of 3 questions.

This. As a severely hearing-impaired individual, context is EVERYTHING in a conversation. Or, like, 95%. In all but the best environments, I'm not actually hearing what you're saying, I'm pattern matching your garbled sounds to the closet logical words my brain can think of. The narrower the context, the better and faster I can do this.

This is why, for example, I don't answer unexpected phone calls. If I don't know the initial context of the call, the first minute is going to be very confusing for both parties.

burntwater is absolutely correct.

The human brain is remarkably good at filling in the blanks.

I rely on context, plus lip-reading, plus the sounds I do hear to figure out the rest.

For context - I'm not severely hearing impaired - I only have a mild-to-moderate loss in both ears, but it's enough to hamper me in normal conversations, particularly in group settings or noisy environments. I use Siemens hearing aids at work, at church etc. - basically, anything that's not 1:1, or where I can't easily ask them to repeat things constantly.

I really really am bad at hearing anything in a noisy environment yet I was a bartender for 3 years and never had a problem getting someone's order. You get used to reading people's lips given that there is only a limited amount of things they could be ordering.

Very often I didn't understand what the clients were talking to me about but then I'd hear keywords like "beer" or "tequila" and the quantity they want is very often requested using hand gestures (finger count).

Even then, the usual conversation between a bartender and the client is very short. To the contrary, when getting together with a bunch of friends you have to listen to entire stories which is way harder.