Posts Tagged 'hearing aid circuit noise'

The Upgrade part 3: Will hissssssstory repeat itself?


the mighty chipolata

“Good news, no great change since your last hearing test”, announced the charming audiologist as I handed the sweaty button-push back. “There’s a mild loss in the low frequencies, but nothing significant”.

I peered at the screen while she did a bit of wire untangling for the next bit, and beamed with pride as I spotted a perfect 0dB threshold in both ears at 4KHz. I always like to do well in a test, but zero dB, wow. This was actually 10dB better than it was back in 2010, so I surmised that I should be able to enjoy the hissing of leaves on the trees, the hissing of the sea, and the hissing of hearing aid circuitry for many more years to come. In fact, if things kept up at this rate of improvement, I might even be able to hear the hissing of other people’s hearing aid circuitry in five years’ time.

“Okay, you know the drill”, said the charming audiologist, as sound probes were wiggled into my ears and the chipolatas were wired up ready for programming. The Oticons, now prostrate and deaf on the table, looked tiny and vulnerable in comparison; I remembered my tragic abandonment of the Siemens Chroma S back in 2012 and vowed that this time, the Oticons were coming home with me until I knew that things were going to be alright. If the performance of the mighty chipolatas matched up to their size, I would be happy to let the Oticons go to NHS hearing aid heaven. If it didn’t…well, it didn’t bear thinking about, so I decided not to, just yet.

After the initial programming, the charming audiologist set about a bit of on-screen fiddling with settings, and I started to become anxious every time a hiss or distortion entered the setup. I wished, not for the first time, that I could do the fiddling bit myself, but after a short while, her work was done and the moment of truth arrived.

“Right, I’m just going to talk for a bit so that you can tell me how it sounds”, she said. I listened carefully, relieved that although I could hear some hiss thanks to my freak bat ear peak at 4KHz, it was nowhere near as loud as the last time with the original Danalogics. I’d rather have no hiss at all, but I could live with it. To my cookiebite ears, the 2012 originals had sounded like a basket of chips being lowered into a deep fat fryer at the initial fitting. This time, other than a mild hiss  and air-con sound, there was nothing distinctive to comment on, but there never is in a soundproof room with air-con. Result.

“Sounds okay –  ” I stopped in my tracks.

“Oh… my voice sounds different…not dramatically so, but…different…” I struggled in vain for a description to the sound, but nothing came apart from ‘boingyness’ and I thought I’d better just keep that one to myself since I was supposed to be articulate. I certainly couldn’t hear anything intrusively bad, so after a run-through of the controls and a small tantrum of disbelief upon discovering the fact that there was a volume wheel instead of a push button, no default beep indicator on the volume, and no mute setting, I decided I was ready to return to the outside world.

I thanked the charming audiologist for her genuinely charming and painstaking attentions, slid the sleeping Oticons off the edge of the table into my handbag, and set off with the chipolatas on my ears to experience a whole new world of Danalogic sound.

Siemens v Danalogic: The Pros and Cons

“Oh no…not again!” I exclaimed after going to investigate a high pitched squealing noise and a faint cry of “Help!” coming from the chest of drawers in the bedroom. When I got there, BatteryBot was holding a Danalogic i-FIT 71 with a half open battery door in one hand, and a battery in the other. The only problem was, his hands were no longer attached to his arms. They’d snapped off under the extreme force necessary to open the battery door, and BatteryBot wasn’t happy.

“I’ve broken another finger, I don’t know how they expect old people to get these open”, he said ruefully, as I screwed his hands back on and got him to run his self-testing circuitry protocol to check that everything was working again.

“Pleeeeeeeease can we keep the Chromas instead of these, when you have to give one pair back”, he said, tugging on my heartstrings with his bandaged finger. “The battery doors are much easier to get open.”

“It’s not quite as simple as that,” I said, gently. “I haven’t made my mind up yet, but the Danalogics sound better and they don’t make funny noises or go haywire in response to anything that beeps. They’re great for the piano too. They look marginally nicer and, Iet’s face it, I need all the help I can get in the looks department these days.”

I was still feeling slightly raw after seeing what looked like a shrunken head being interviewed in a student video last week. It had turned out to be me.

“But what about the hissing noise the Danalogics make,” cut in BatteryBot, “you said it was really annoying…and what about the fact they make the back of your ears sore because they grip on really tightly…and, and…”, he was trying to pull out all the stops now, “…and what about the ea-”

“Look.” I said firmly, “Don’t keep going on about the Easter Bunny. We can reshape his head to fit the Danalogics if I have to give the Chromas back to Clinic O. He won’t know any better, he’s only made of Plasticine…oh, sorry, I didn’t mean that the way it sounds”.

It was too late, the damage had been done.

“Well I’m only made out of a kitchen cupboard door latch and some bits the plumber left behind, I hope you don’t talk about me like that”, sobbed BatteryBot.

“Shhhhhhhh! You’re about to short circuit”, I said, noting once more the strange Sean Connery sound of my dental fricatives of late. I leant forward and whispered clandestinely into BatteryBot’s auditory sensors:

“Don’t mention the cupboard door latch on here again. People think you’re a real robot; If this gets out, we’re finished.”

Siemens v Danalogic : The Playoff

Last week, the very nice and very helpful senior audiologist at clinic O gave me two sets of hearing aids to compare, to see which works best for my dubious activities outwith the soundproofed room. Hearing aid No. 1 is my original Siemens Chroma S, and hearing aid No. 2 is the newer Danalogic i-FIT 71. The Danalogic had originally been given the heave-ho after its first fitting, because of the intolerably loud circuit noise which was being picked up by the hiss-sensitive cookie bite ears. It has since been slightly de-hissed, and is being given a second chance to see whether the benefits of slightly better overall sound quality outweigh the downside of listening to digital tinnitus all day long.

At the weekend, I decided to blow the dust off the piano, in order to subject both aids to a rigorous and highly scientific test of their music handling capabilities. Using every ounce of my musical talent, I wrote a technically challenging composition, designed to put silence to the test every bit as much as sound. The opening sequence invites the pianist to channel the spirit of John Cage while the Delayed Startup beeps of the i-FIT 71 count down to Power On. The climax of the piece, in bars 6-8, involves a technically demanding sequence of three triad chords in a row, situated right in the middle of the cookie bite zone, a notorious spot for over-amplification in the past.

All that was missing was a functional MRI scan to find out what was going down in the Cookie Bite Auditory Cortex while all this was going on, but who needs a £100,000 scanner when you’ve got a nice sharp HB pencil to to draw what you’re hearing instead.

The results show that, on music, the Danalogic is the clear winner. It hissed its way consistently through the test from start to finish,  but there was no great distortion of sound, just louder hissing when notes are sounded. The Siemens, on the other hand, was nice and quiet on silence, but couldn’t resist creating a musical accompaniment all of its own to the piano. This consists of a gentle rattling noise on notes lower than C3, and random chirps and beeps everywhere else. The keys between G5 and B5 remain scarily loud and have to be approached with extreme caution.

Winner of the Piano Playoff Test: The Danalogic i-FIT 71.

Coming up next: The Mumbling Student Test. Will the Chroma S fight back?

Bute Newt

With the days finally lengthening and warming up, it was a wildlife extravaganza on Bute this weekend. The daffodils were out, a green carpet of wild garlic leaves had sprouted in the woods at the back of the house, and white-tailed deer bounced gaily out of the undergrowth on the side of the Suidhe hill, as we climbed our way laboriously to the top.

“Quick, I’ve found a tiny snake!”, I shouted excitedly to the spouse, after a fleeting movement in the grass underfoot caught my eye. A closer inspection of the stripy brown reptile hiding in the greenery revealed that the snake had four legs and was actually a common newt.

“Dunno what made me think it was a snake”, I said, suddenly noticing the hiss in my ears again.

ssssssssssssssssssssssssssssss

Oh dear. A week, as they say, is a long time in politics, but it’s an even longer time in hissing hearing aids. Ever since allowing myself to be persuaded by Clinic O that the abominable static noise emanating from the circuitry of my newly acquired Danalogic i-FIT 71 aids might be something which could be conquered by the neural plasticity of my auditory cortex, ie I’d get used to it, I’ve somewhat regretted it.

Although it is a marvellous coping phenomenon that my brain fashions the hiss into the phantom noise of a shower when I am in the bathroom, and the noise of a deep fat fryer when I am in the kitchen, its creativity is stumped when I’m in silence. In quiet surroundings, the hiss sounds just like an annoyingly hissing pair of hearing aids. It’s loud enough to mask other high frequency sounds, and I’m worried that an escaped rattlesnake could sneak up behind me undetected.

Demented in the empty office at work on Wednesday, I sought solace in the perfect place to escape from the hiss. The studio. “Budge up!” I said enthusiastically to a student, who had been reclining comfortably on the sofa with her book until my unexpected arrival with my laptop disturbed her. I listened for a bit to make sure that the soundscape was to my liking, then sat down to attend to my daily mountain of emails. Ah, this was more like it. The hiss was slightly less audible. The studio was only half full of students, but they were working in groups so were producing plenty of chat. I was slightly disappointed that there was no loud music, but was heartened to hear the reassuring rumble of the extraction system overhead. The noise of 60 feet of exposed industrial ducting was going some way towards drowning out the hiss but was not eliminating it entirely. I was on the verge of asking someone to open a window so that the noise of the nearby motorway could help out a bit, when an even better solution presented itself in the form of some impromptu furniture moving by students. Several chairs and desks were dragged mercilessly back and forth across the bare concrete floor, producing a rich variety of soothing scraping and grinding noises. Ahhhh. That’s better I said to myself, I can’t even hear the hiss now when I listen out for it. Maybe they were right at Clinic O after all!

Then it all got spoiled. Without warning, a heavy 6 by 4 foot sheet of mdf was knocked over by accident, causing a very loud bang. Although the bang itself was extremely acoustically satisfying in the bare concrete space, it was followed by a pregnant silence as everyone waited to see if there had been a casualty. This was all the hiss needed in order to sneak back in to my consciousness. Ssssssssss. Then to my relief, a round of shrieking and laughter began, followed by a purposeful bout of hammering to fix the damage. Phew.

The studio door banged open and shut with a pleasing regularity throughout, and every so often, the plumbing let out its usual foghorn blast every time a tap was turned on. As I basked in the racket, I reflected that the only thing that could possibly make the ambience more perfect for masking unwanted hissing noises from hearing aids, was the sounding of the twice weekly fire alarm test.

“Can I talk to you about my project?” said a student who had just wandered into my field of vision.

“Certainly”, I said, hoping there was going to be plenty to look at.


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