Me and three guys in the pub were struggling to settle an argument about who was the best lover when one guy suggested he had a sound measuring device and we should all take it in turns to record how loud our wives scream during sex.

We all agreed, so a week later we all met in the pub to discuss our results over a pint. "Well I did the experiment," said the first guy, "and the device measured 89 decibels, beat that." "No problem," said the second guy smugly. "I did the experiment and the device measured 98 decibels. Now, what do you say about that?" "Not bad," I replied, "but when I did the experiment the device measured in at a whopping 128 decibels." "128 decibels?" said the first guy. "How on earth did you get your missus to scream that loud while you were having sex?" "Easy," I replied, "she walked in while I was f***ing her sister."