And amplification here makes sure that people at the back can hear as clearly as people in the front row.

Or, as I used to think on singers nights in Llandudno for example, that everyone taking a turn would be heard.

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I'm mostly in sessions in main bars of pubs these days. Background noise goes with that and isn't usually (I have for example struggled to here Irish pipes 3ft from me) a problem and theres not usually anything you can do if it does get silly, apart from hope next week is quieter.