16 ms·

This is nifty. My father has hearing loss and it's bad enough that not only does he use hearing aids, he is constantly turning them up until they feedback and

by korethr 12y ago

This is nifty. My father has hearing loss and it's bad enough that not only does he use hearing aids, he is constantly turning them up until they feedback and start ringing. He doesn't hear the ringing, but I do, and I have some hearing damage of my own. And he wonders why his hearing aids go through batteries so fast. Their description of how hearing loss works gives me some ideas on how I can help my father manage his hearing loss better than just constantly buying batteries. However, I do have one complaint with the article, and that's their (mis)use of terminology, specifically, dynamic range. Dynamic range is not, as they claim, the range of frequencies one can hear, from lowest to highest (e.g. 20Hz-20kHz). That's bandwidth. What dynamic range is, is the ratio of quietest to loudest sounds possible, often expressed in dB.[1] For example, as they mention, human hearing has about 120dB of dynamic range. An audio CD can encode a dynamic range of 96dB. The 24-bit files professional audio studios work with can represent up to 144dB of dynamic range. Perhaps it's a pedantic distinction, but using already existing terms for what you mean to say is less likely to cause confusion than misusing one that means something else. 1. https://en.wikipedia.org/wiki/Dynamic_range https://en.wikipedia.org/wiki/Dynamic_range

Stratoscope 12y ago
You're not being pedantic at all. It's a fairly egregious error for an article about hearing. It would be like an article about a camera talking about its fast f/1.4 shutter speed.
- bigiain 12y ago
  Curiously, that sort of language is used by camera people. Aperture and shutter speed are not the same thing, but they are inextricably linked to each other (in a way that dynamic range (in the amplitude sense) and frequency response/range are not nearly so linked). In a "camera article", the phrase " ... its fast f/1.4 shutter speed." would probably be in the context of saying something about one or more of the sensor's size, sensitivity, or noise-floor. http://en.wikipedia.org/wiki/Lens_speed http://en.wikipedia.org/wiki/Lens_speed "Lens speed refers to the maximum aperture diameter, or minimum f-number, of a photographic lens. A lens with a larger maximum aperture (that is, a smaller minimum f-number) is called a "fast lens" because it delivers more light intensity (illuminance) to the focal plane, achieving the same exposure with a faster shutter speed."
  - Stratoscope 12y ago
    Sorry to disagree, but a knowledgeable camera person would never talk about a "fast f/1.4 shutter speed". A camera article, review, or blog post that said that would be loudly criticized in the comments. The phrase just doesn't make sense - that's why I chose it as an analogy. It especially doesn't make sense as a figure of speech referring to some characteristic of the sensor. A more sensitive and less noisy sensor may let you use a higher ISO setting and therefore allow either a faster shutter speed or a smaller aperture for the same overall exposure. A lens with a wider aperture would allow you to use a faster shutter speed or a lower ISO with the same exposure. Similarly, a slow shutter speed would allow you to use a smaller aperture for more depth of field, or a lower ISO setting for less noise. Or a fast shutter speed would allow you to a wider aperture to blur the background. Again all with the same overall exposure. Aperture, shutter speed, and ISO setting are closely linked - changing any one of them will affect your overall exposure, or you can change two or all three of them in combination to get the same exposure while altering other characteristics like motion blur or depth of field. But they are three very different things, and even in casual conversation someone who knows cameras would not mix them up. BTW this goes way back to the film days. Shutter speed and aperture work the same now as they did then, the only difference is that you changed ISO rating by buying a new roll of film instead of turning a dial.
    - hrjet 12y ago
      I think you are missing a characteristic of lenses called the f-ratio, which is sometimes described as fast or slow. This is not specific to cameras; it is a general term used in optics. The f-ratio is the ratio of the aperture to the focal length. Even telescope lenses and mirrors are described similarly. For example, a telescope with an f/4 mirror can be described as a fast telescope. Not only that, a lot of the terms have been misappropriated in camera lingo. The camera folks express aperture as an f-ratio, which is extremely confusing.
      - Stratoscope 12y ago
        Thank you, you are absolutely right! I should have said "f-ratio" everywhere I used "aperture". I'll leave my previous comment in its incorrect state in the hope that people will see yours to correct and clarify it. :-) > The camera folks express aperture as an f-ratio, which is extremely confusing. Isn't it the other way around? I think the mistake we self-proclaimed "knowledgeable" camera folks make is using the term "aperture" where we really should say f-ratio. For example, I have two Olympus Micro Four Thirds lenses that are both f/1.8: a 45mm and a 75mm. Looking at these lenses it's pretty obvious that the f/1.8 is an f-ratio: the front element of the 75mm is much wider than the 45mm, as you'd expect. So thanks to your comment, I will endeavor to use "f-ratio" where I've been misusing "aperture".
- JshWright 12y ago
  While the phrase "fast f/1.4 shutter speed" doesn't make perfect sense, it's not uncommon to call a f/1.4 lens a "fast" lens.
  - Stratoscope 12y ago
    Indeed that is true. Some of my lenses are much faster than others! A fast lens does let me use a fast shutter speed, and as Wikipedia describes, that's where the phrases "fast lens", "slow lens", and "lens speed" came from. But "fast f/1.4 shutter speed" doesn't just not make perfect sense, it doesn't make any sense. That's why I chose it as an analogy. The phrase doesn't mention lenses at all, it's talking about the shutter. And shutter speeds are measured in seconds or fractions of a second, not f-stops.
analog31 12y ago
It seems to me that a simple way to eliminate the feedback issue is to separate the microphone from the speaker. Hearing loss runs in my family, so I've watched my relatives struggle with hearing aids, and I've decided that when it's time for me: 1) I will build it myself and figure out the details, to hell with the audiologists and their racket. 2. I will carry the microphone and amplifier in my shirt pocket. No more feedback. Ironically, with the advent of personal electronics, everybody wears some sort of gizmo on their body, so I think we could just persuade the elderly that hearing aids don't need to be invisible any more.
- Dwolb 12y ago
  I'm not a hearing aid expert but the microphone and earpiece may currently be tightly coupled because it has to be. That is, human ears are very sensitive to phase shifts and time delays. Placing the microphone in a location that is not your ear may throw off your hearing somewhat (possibly ability to locate from where a sound originated).
  - roberthahn 12y ago
    I can vouch for this. I used to have an FM system - this is a mic that transmits on a very specific FM frequency to a receiver that's paired with my hearing aids. I loved it because I could easily use it to hear people near me in loud rooms, but it sucked in meeting rooms. The reason why is that I would hear someone speaking through my hearing aids and through the mic - at slightly different times. This is the phase shift Dwolb speaks of. This reduced clarity significantly. That said, if analog31 wants to wear the mic on his shirt, that distance is actually good enough for most 1 to 1 conversations. Just understand that you're trading off "spatial perception" (no left/right balance if only one mic).
  - Kluny 12y ago
    As a hearing aid user: my spatial awareness (as provided by sound information) is pretty much borked anyway. If I can't see where a sound is coming from I have no way of knowing what direction it's from or how far off it is. Even a small amount of hearing loss can cause this problem.
varunsrin 12y ago
Not a pedantic distinction at all - on a second read, I completely see the confusion, and I'm going to reword the article to separate the concepts of dynamic range (which is just a dB value) and dynamic ranges across a frequency spectrum more clearly.
deleted 12y ago
[deleted]
adrianhoward 12y ago
"My father has hearing loss and it's bad enough that not only does he use hearing aids, he is constantly turning them up until they feedback and start ringing." This may also be a sign that the hearing aid wasn't fitted properly — or the shape of your father's ear has changed a bit since it was fitted. Poor fit makes it much more likely for this to happen (coz speaker and mike have a more open channel between 'em, and more ambient noise gets in so folk turn 'em up more). (My dad has similar problems until he got a new ear canal mould taken.) It may also be a sign that you're dad's hearing loss has changed since the hearing aid was chosen and he needs it adjusting, or a different type. Feedback is usually a sign that something needs fixing ;-)
- hibbelig 12y ago
  For a while, I had the problem that I got feedback depending on the temperature: Going out into the winter cold was enough to change the shape of the hearing aid versus my ear so that the fit was not tight enough anymore. What I mean to say is that hearing aids are a piece of technology that it tuned (pimped?) so much that there is very little buffer. Today, my new hearing aids detect feedback and compensate, but of course that will eliminate sounds I need to hear, as well.
ubercow13 12y ago
Did they change this after your comment? >Dynamic range is the difference between the loudest and quietest sound you can hear.
deleted 12y ago
[deleted]

by korethr 12y ago

Stratoscope 12y ago

You're not being pedantic at all. It's a fairly egregious error for an article about hearing. It would be like an article about a camera talking about its fast f/1.4 shutter speed.

bigiain 12y ago
Curiously, that sort of language is used by camera people. Aperture and shutter speed are not the same thing, but they are inextricably linked to each other (in a way that dynamic range (in the amplitude sense) and frequency response/range are not nearly so linked). In a "camera article", the phrase " ... its fast f/1.4 shutter speed." would probably be in the context of saying something about one or more of the sensor's size, sensitivity, or noise-floor. http://en.wikipedia.org/wiki/Lens_speed http://en.wikipedia.org/wiki/Lens_speed "Lens speed refers to the maximum aperture diameter, or minimum f-number, of a photographic lens. A lens with a larger maximum aperture (that is, a smaller minimum f-number) is called a "fast lens" because it delivers more light intensity (illuminance) to the focal plane, achieving the same exposure with a faster shutter speed."
- Stratoscope 12y ago
  Sorry to disagree, but a knowledgeable camera person would never talk about a "fast f/1.4 shutter speed". A camera article, review, or blog post that said that would be loudly criticized in the comments. The phrase just doesn't make sense - that's why I chose it as an analogy. It especially doesn't make sense as a figure of speech referring to some characteristic of the sensor. A more sensitive and less noisy sensor may let you use a higher ISO setting and therefore allow either a faster shutter speed or a smaller aperture for the same overall exposure. A lens with a wider aperture would allow you to use a faster shutter speed or a lower ISO with the same exposure. Similarly, a slow shutter speed would allow you to use a smaller aperture for more depth of field, or a lower ISO setting for less noise. Or a fast shutter speed would allow you to a wider aperture to blur the background. Again all with the same overall exposure. Aperture, shutter speed, and ISO setting are closely linked - changing any one of them will affect your overall exposure, or you can change two or all three of them in combination to get the same exposure while altering other characteristics like motion blur or depth of field. But they are three very different things, and even in casual conversation someone who knows cameras would not mix them up. BTW this goes way back to the film days. Shutter speed and aperture work the same now as they did then, the only difference is that you changed ISO rating by buying a new roll of film instead of turning a dial.
  - hrjet 12y ago
    I think you are missing a characteristic of lenses called the f-ratio, which is sometimes described as fast or slow. This is not specific to cameras; it is a general term used in optics. The f-ratio is the ratio of the aperture to the focal length. Even telescope lenses and mirrors are described similarly. For example, a telescope with an f/4 mirror can be described as a fast telescope. Not only that, a lot of the terms have been misappropriated in camera lingo. The camera folks express aperture as an f-ratio, which is extremely confusing.
    - Stratoscope 12y ago
      Thank you, you are absolutely right! I should have said "f-ratio" everywhere I used "aperture". I'll leave my previous comment in its incorrect state in the hope that people will see yours to correct and clarify it. :-) > The camera folks express aperture as an f-ratio, which is extremely confusing. Isn't it the other way around? I think the mistake we self-proclaimed "knowledgeable" camera folks make is using the term "aperture" where we really should say f-ratio. For example, I have two Olympus Micro Four Thirds lenses that are both f/1.8: a 45mm and a 75mm. Looking at these lenses it's pretty obvious that the f/1.8 is an f-ratio: the front element of the 75mm is much wider than the 45mm, as you'd expect. So thanks to your comment, I will endeavor to use "f-ratio" where I've been misusing "aperture".
JshWright 12y ago
While the phrase "fast f/1.4 shutter speed" doesn't make perfect sense, it's not uncommon to call a f/1.4 lens a "fast" lens.
- Stratoscope 12y ago
  Indeed that is true. Some of my lenses are much faster than others! A fast lens does let me use a fast shutter speed, and as Wikipedia describes, that's where the phrases "fast lens", "slow lens", and "lens speed" came from. But "fast f/1.4 shutter speed" doesn't just not make perfect sense, it doesn't make any sense. That's why I chose it as an analogy. The phrase doesn't mention lenses at all, it's talking about the shutter. And shutter speeds are measured in seconds or fractions of a second, not f-stops.

analog31 12y ago

It seems to me that a simple way to eliminate the feedback issue is to separate the microphone from the speaker. Hearing loss runs in my family, so I've watched my relatives struggle with hearing aids, and I've decided that when it's time for me: 1) I will build it myself and figure out the details, to hell with the audiologists and their racket. 2. I will carry the microphone and amplifier in my shirt pocket. No more feedback. Ironically, with the advent of personal electronics, everybody wears some sort of gizmo on their body, so I think we could just persuade the elderly that hearing aids don't need to be invisible any more.

Dwolb 12y ago
I'm not a hearing aid expert but the microphone and earpiece may currently be tightly coupled because it has to be. That is, human ears are very sensitive to phase shifts and time delays. Placing the microphone in a location that is not your ear may throw off your hearing somewhat (possibly ability to locate from where a sound originated).
- roberthahn 12y ago
  I can vouch for this. I used to have an FM system - this is a mic that transmits on a very specific FM frequency to a receiver that's paired with my hearing aids. I loved it because I could easily use it to hear people near me in loud rooms, but it sucked in meeting rooms. The reason why is that I would hear someone speaking through my hearing aids and through the mic - at slightly different times. This is the phase shift Dwolb speaks of. This reduced clarity significantly. That said, if analog31 wants to wear the mic on his shirt, that distance is actually good enough for most 1 to 1 conversations. Just understand that you're trading off "spatial perception" (no left/right balance if only one mic).
- Kluny 12y ago
  As a hearing aid user: my spatial awareness (as provided by sound information) is pretty much borked anyway. If I can't see where a sound is coming from I have no way of knowing what direction it's from or how far off it is. Even a small amount of hearing loss can cause this problem.

varunsrin 12y ago

Not a pedantic distinction at all - on a second read, I completely see the confusion, and I'm going to reword the article to separate the concepts of dynamic range (which is just a dB value) and dynamic ranges across a frequency spectrum more clearly.

deleted 12y ago

[deleted]

adrianhoward 12y ago

"My father has hearing loss and it's bad enough that not only does he use hearing aids, he is constantly turning them up until they feedback and start ringing." This may also be a sign that the hearing aid wasn't fitted properly — or the shape of your father's ear has changed a bit since it was fitted. Poor fit makes it much more likely for this to happen (coz speaker and mike have a more open channel between 'em, and more ambient noise gets in so folk turn 'em up more). (My dad has similar problems until he got a new ear canal mould taken.) It may also be a sign that you're dad's hearing loss has changed since the hearing aid was chosen and he needs it adjusting, or a different type. Feedback is usually a sign that something needs fixing ;-)

hibbelig 12y ago
For a while, I had the problem that I got feedback depending on the temperature: Going out into the winter cold was enough to change the shape of the hearing aid versus my ear so that the fit was not tight enough anymore. What I mean to say is that hearing aids are a piece of technology that it tuned (pimped?) so much that there is very little buffer. Today, my new hearing aids detect feedback and compensate, but of course that will eliminate sounds I need to hear, as well.

ubercow13 12y ago

Did they change this after your comment? >Dynamic range is the difference between the loudest and quietest sound you can hear.

deleted 12y ago

[deleted]