Why I cannot hear what you are saying

Several months ago, egged on by Others here, I submitted to a free hearing consultation in Newbridge. The man was thorough enough with his tests and concluded that I had considerable hearing loss and needed one of his hearing aids for five or six grand. He let me try one and showed that it improved my ability to hear quiet sounds. No brainer. But I was and still am not convinced that it would help much in a noisy situation which is where I suffer most.

Since then I purchased a small battery-powered gizmo - basically a microphone, amplifier with volume and tone controls, and earbuds. I improved the latter by purchasing the noise isolating kind that reduce ambient sound.

I suffer from tinnitus, which means that I hear constant "noise" in the higher frequencies. I'm in the lounge at the moment: Ali is sitting opposite me and talking to Caroline on the side. There is no-one else in the room. The level of my tinnitus noise is a little below that of their conversation, and I can make out what they are saying with no problem. But if they were speaking more quietly I might not because the tinnitus noise would mask theirs. Without doubt my gizmo would help in this case, even though its own electronic noise is quite audible to me.

In the praise in our meetings with its loud accompaniment (grand piano, drums, bass, trumpet, guitars), or at community dinner time (think 30 people with small children in a room with a low ceiling) another effect kicks in - my ears start to distort the sound to the point that it can become uncomfortable. When I use my gizmo it amplifies this cacophony and only makes it worse. QED. Even with the noise isolating earbuds which, frankly, do not isolate ambient noise very much.

Distortion is exacerbated when there are many sounds together, because the distortion mixes them up. Technically speaking the non-linearity of distortion can, from two sounds at different frequencies, create new sounds at the sum and at the difference of those frequencies - so two sounds become four, and four become... It is those additional sounds, I think, that make it so uncomfortable.

In the praise in our meetings I find I can actually hear better with a finger in each ear, because it reduces the level below that at which it distorts.

The undamaged human hearing is amazing. It can can distinguish about 10 graduations per semitone over 10 octaves (20Hz to 20,000Hz), and can safely detect sound levels over a 130dB range - that's a ratio of 1 to 10,000,000,000,000 times. And, of course, it is stereophonic so that it can spatially locate sounds.  In contrast the dynamic range of my hearing is severely limited especially at higher frequencies - I can't hear sounds substantially below the threshold imposed by my tinnitus, and sounds louder than an upper threshold distort and become uncomfortable. Which is strange recompense for someone who has commented on the present day departure from hi-fi.

For what it is worth, I believe my legendary Aunt Mary suffered in the same way - she used to plug her ears with cotton wool to reduce the discomfort.

Whilst people try to be understanding, there is without doubt more of a stigma over wearing any sort of hearing aid than, for example, wearing glasses. Kind of on a par with wearing no shoes. People say things behind you back, or give odd glances. Which is why I don't go around with a pair of ear defenders on (except when doing building work).