Fritz Sennheiser, the founder of the audio company of the same name, has died. He was 98 and was an electronics expert who pioneered many developments.

Mr Sennheiser changed the whole concept of earphones from their old bulky format to the sophisticated open headphones we use today.

Back in 1936, he was experimenting with acoustic reverberation and he also pioneered radio microphones and developed the art of using directional rifle-like microphones.

His company also encompassed the Neuman group that specialises in professional studio equipment.

The noise-cancelling headsets he created still sell today and many of his innovations have been imitated by other manufacturers, but never truly equalled.

Mr Sennheiser retired from the company when he was 70, but continued his interest in the firm that is now run by his son, Prof Jorg Sennheiser.

I couldn't contemplate getting on a long flight without my Sennheiser noise-cancelling earphones.

Thanks, Fritz.

Graham Knight