1979 flew back from Turkey with cold symptoms. Woke up next morning with high frequency deafness and hissing tinnitus in both ears. Hearing deteriorated slowly since but tinnitus now less bothersome maybe because of blood pressure pills.
First NHS analogue hearing aids under performed in left ear possibly due to bone conduction from headphones during testing. Started making body worn analogue hearing aids using op amps, transducers from Knowles Electronics . Attempts at high pass, band pass filters, gain control, bird listener were successful. Attempts at frequency reduction and directional control unsuccessful. First NHS digital aids under performed also. Got digital hearing aids programming hardware and soft ware from Ebay and started home programming.
Now using Phonak Naida M70SP’s (best for direction) and Signia 13 5NX (best for dominant voice).

Amended programme for Naidas using NAL/NAL2 non-tonal and modified custom ear defender earmoulds, using Audio Direct using automatic Roger programme with hearing aid mics muted. .
Right ear 250hz 65db, 500hz 65db, 750hz 80db, 1000hz 75db not heard, 1500hz to 6000hz 40db not heard .
Left ear 250hz 65db, 500hz 70db, 750hz 80db, 1000hz to 6000hz 50db not heard.

Big problem following speech in noise - but not impossible. Roger pen with automatic Roger programme in pointing mode can be very useful.to single out the voice you want to hear.

I can hear the “s” sound without hearing aids.
if I cup my hands tightly round my ears and say the word “sausages” I can hear all 3 “s” sounds clearly.
Studio broadcast news items I get every word using TV connector.