LTNman
The distance from the house to the runway centreline is about 150m. "A jet aircraft taking off 25m away will be 140 dB(A)" you quoted, but that's obviously a very crude measurement. Is that for a BAC 1-11 or an A320neo? - quite a difference between the two so the actual noise would have to be measured for it to mean anything. Maybe one of the newspapers could pay for that to be done for a start. I can fully appreciate that the family finds the noise very intrusive but it's certainly true that they MUST have known it would be before moving in - especially as it's alleged that both husband and wife worked for ATC Lasham at SEN.
Their main gripe seems to be that aircraft using Taxiway Charlie causes them most annoyance, yet that has been in use since the late 1950s. The only time it wasn't used by A320-sized aircraft was for a period of perhaps 12 months, maybe two years ago, when it suffered instability problems; after that it was rebuilt and put back into regular use. I really do find it difficult to feel sympathy with their attitude.