Hearing aid design

[klem kedidelhopper]

I have known that my hearing has been getting worse over the last few
years. I recently had a hearing test to confirm this and compared it
to a similar test which was done 8 years ago. This confirmed my
suspicions. According to the most recent results my speech frequencies
are down about 30 DB more than previously noted. And I'm pretty
certain that 8.0KHZ and above is even worse. The tinitus also tends
exacerbate the problems further.

The test was rather interesting and informative and not unpleasant,
until that is the examiner switched into "salesman" mode. I realize
that these new aids have many new bells and whistles many that I will
never use. In any case, to make a long story shorter, 4000.00 is not
within my budget at this time. Unfortunately there is no money at this
time for anything.

So I would like to ask, (and I've tried to pursue this before) but
unsuccessfully is there any information on the DIY construction of a
pocket unit with an earphone which has either a high pass filter
circuit which rolls off the low frequencies, or a graphic equalizer
that can be set for the frequency response desired?

I may be oversimplifying this a bit but it seems to me that if the
amplifier had a response curve which was the inverse of my hearing
curve, (similar to an RIAA or NAB equalized curve) then the amplifier
would "pre compensate" for my deficiency.

I have found some circuits on the net but they don't seem to be
frequency compensated. Amplifying the entire spectrum would be counter
productive. Perhaps I could try coupling a full range amplifier using
a very small capacitor on the input to roll off the lows.

One other option is this: I have my fathers old hearing aids. He
passed away in 1993. I found his old test, and his response curves
were very similar to mine. These are naturally much larger units than
what's available today and although they're not a perfect fit, they
do fit, and could I suppose be used. I am also told that new molds
could be made and they could be "refitted" to my ear shape if I so
desire as well.

I asked the "salesman" a hypothetical question. And that was if I did
decide to try to use them what was the technology back in 1990? Were
the aids frequency compensated or were they just a plain flat response
amplifier? I don't know if the answer I received was bullshit or not
but in any case it was not a positive one. Does anyone know the answer
to this?

I'm semi retired now so I do have some time to fart around with
something like this if I had the appropriate information. According to
the test, I need to make up 55DB at 3.0 and 4.0 KHZ.
I really wouldn't mind carrying a box in my shirt pocket with an
earphone. Any help with such a project would be most sincerely
appreciated. Lenny

 

[hrhofmann@att.net]

On Feb 22, 9:07 am, klem kedidelhopper <captainvideo462...@gmail.com>
wrote:

I have known that my hearing has been getting worse over the last few
years. I recently had a hearing test to confirm this and compared it
to a similar test which was done 8 years ago. This confirmed my
suspicions. According to the most recent results my speech frequencies
are down about 30 DB more than previously noted. And I'm pretty
certain that 8.0KHZ and above is even worse. The tinitus also tends
exacerbate the problems further.

The test was rather interesting and informative and not unpleasant,
until that is the examiner switched into "salesman" mode. I realize
that these new aids have many new bells and whistles many that I will
never use. In any case, to make a long story shorter, 4000.00 is not
within my budget at this time. Unfortunately there is no money at this
time for anything.

So I would like to ask, (and I've tried to pursue this before) but
unsuccessfully is there any information on the DIY construction of a
pocket unit with an earphone which has either a high pass filter
circuit which rolls off the low frequencies, or a graphic equalizer
that can be set for the frequency response desired?

I may be oversimplifying this a bit but it seems to me that if the
amplifier had a response curve which was the inverse of my hearing
curve, (similar to an RIAA or NAB equalized curve) then the amplifier
would  "pre compensate" for my deficiency.

I have found some circuits on the net but they don't seem to be
frequency compensated. Amplifying the entire spectrum would be counter
productive. Perhaps I could try coupling a full range amplifier using
a very small capacitor on the input to roll off the lows.

One other option is this: I have my fathers old hearing aids. He
passed away in 1993. I found his old test, and his response curves
were very similar to mine. These are naturally much larger units than
what's available today and although they're not a perfect fit,  they
do fit, and could I suppose be used. I am also told that new molds
could be made and they could be "refitted" to my ear shape if I so
desire as well.

I asked the "salesman" a hypothetical question. And that was if I did
decide to try to use them what was the technology back in 1990? Were
the aids frequency compensated or were they just a plain flat response
amplifier? I don't know if the answer I received was bullshit or not
but in any case it was not a positive one. Does anyone know the answer
to this?

I'm semi retired now so I do have some time to fart around with
something like this if I had the appropriate information. According to
the test, I need to make up 55DB at 3.0 and 4.0 KHZ.
I really wouldn't mind carrying a box in my shirt pocket with an
earphone. Any help with such a project would be most sincerely
appreciated.  Lenny

The $4000 aids are not that much better than the $400 aids I use. My
wife has the $4000 variety, and I have the $400 variety. Unless your
hearing is REALLY bad, the $400 units are fine. I do not get any $$
or anything else for recommending them, but check these out at
HearingHelpExpress.com. I have the Earmate4000 model, very happy
with them for the past 5 years. Before, I could rub my fingers
together right by either ear and hear nothing, with the Earmates, when
I rub my fingers together, I can hear the scraping sounds. That is
how I double-check that they are working.

 

[spamtrap1888]

On Feb 22, 7:07 am, klem kedidelhopper <captainvideo462...@gmail.com>
wrote:

I have known that my hearing has been getting worse over the last few
years. I recently had a hearing test to confirm this and compared it
to a similar test which was done 8 years ago. This confirmed my
suspicions. According to the most recent results my speech frequencies
are down about 30 DB more than previously noted. And I'm pretty
certain that 8.0KHZ and above is even worse. The tinitus also tends
exacerbate the problems further.

The test was rather interesting and informative and not unpleasant,
until that is the examiner switched into "salesman" mode. I realize
that these new aids have many new bells and whistles many that I will
never use. In any case, to make a long story shorter, 4000.00 is not
within my budget at this time. Unfortunately there is no money at this
time for anything.

Thirty years ago, good Starkey aids cost $2K. So $4K is a relatively
good deal.

So I would like to ask, (and I've tried to pursue this before) but
unsuccessfully is there any information on the DIY construction of a
pocket unit with an earphone which has either a high pass filter
circuit which rolls off the low frequencies, or a graphic equalizer
that can be set for the frequency response desired?

See below. But I haven't seen a pocket aid since my GGma's, 40+ years
ago.

I may be oversimplifying this a bit but it seems to me that if the
amplifier had a response curve which was the inverse of my hearing
curve, (similar to an RIAA or NAB equalized curve) then the amplifier
would  "pre compensate" for my deficiency.

I have found some circuits on the net but they don't seem to be
frequency compensated. Amplifying the entire spectrum would be counter
productive. Perhaps I could try coupling a full range amplifier using
a very small capacitor on the input to roll off the lows.

One other option is this: I have my fathers old hearing aids. He
passed away in 1993. I found his old test, and his response curves
were very similar to mine. These are naturally much larger units than
what's available today and although they're not a perfect fit,  they
do fit, and could I suppose be used. I am also told that new molds
could be made and they could be "refitted" to my ear shape if I so
desire as well.

I asked the "salesman" a hypothetical question. And that was if I did
decide to try to use them what was the technology back in 1990? Were
the aids frequency compensated or were they just a plain flat response
amplifier? I don't know if the answer I received was bullshit or not
but in any case it was not a positive one. Does anyone know the answer
to this?

Depends on the make and model. It could have been.

I'm semi retired now so I do have some time to fart around with
something like this if I had the appropriate information. According to
the test, I need to make up 55DB at 3.0 and 4.0 KHZ.
I really wouldn't mind carrying a box in my shirt pocket with an
earphone. Any help with such a project would be most sincerely
appreciated.  Lenny

I used to hang out with hearing aid types. There was (or maybe still
is) a company that designed transducers for hearing aids, Knowles
Electronics:

http://www.nytimes.com/1988/04/23/obituaries/hugh-s-knowles-an-inventor-is-dead-at-83.html

One of his employees, Mead Killion, was interested in designing aids
that compensated for frequency loss, with the aim of producing high
fidelity hearing aids. (Scroll down till you get his doctoral
dissertation.)

http://www.etymotic.com/publications/

That was thirty years ago, so I imagine things have come a long way.

One problem at that time, at least, was unlimited high frequency
response of the microphone. You couldn't talk to my HOH boss when we
got to the end of any hallway, because his hearing aids automatically
stopped amplifying when they got close to the ultrasonic motion
detectors, when the sound output overloaded them.

 

[mike]

On 2/22/2012 7:07 AM, klem kedidelhopper wrote:

I have known that my hearing has been getting worse over the last few
years. I recently had a hearing test to confirm this and compared it
to a similar test which was done 8 years ago. This confirmed my
suspicions. According to the most recent results my speech frequencies
are down about 30 DB more than previously noted. And I'm pretty
certain that 8.0KHZ and above is even worse. The tinitus also tends
exacerbate the problems further.

The test was rather interesting and informative and not unpleasant,
until that is the examiner switched into "salesman" mode. I realize
that these new aids have many new bells and whistles many that I will
never use. In any case, to make a long story shorter, 4000.00 is not
within my budget at this time. Unfortunately there is no money at this
time for anything.

So I would like to ask, (and I've tried to pursue this before) but
unsuccessfully is there any information on the DIY construction of a
pocket unit with an earphone which has either a high pass filter
circuit which rolls off the low frequencies, or a graphic equalizer
that can be set for the frequency response desired?

I may be oversimplifying this a bit but it seems to me that if the
amplifier had a response curve which was the inverse of my hearing
curve, (similar to an RIAA or NAB equalized curve) then the amplifier
would "pre compensate" for my deficiency.

I have found some circuits on the net but they don't seem to be
frequency compensated. Amplifying the entire spectrum would be counter
productive. Perhaps I could try coupling a full range amplifier using
a very small capacitor on the input to roll off the lows.

One other option is this: I have my fathers old hearing aids. He
passed away in 1993. I found his old test, and his response curves
were very similar to mine. These are naturally much larger units than
what's available today and although they're not a perfect fit, they
do fit, and could I suppose be used. I am also told that new molds
could be made and they could be "refitted" to my ear shape if I so
desire as well.

I asked the "salesman" a hypothetical question. And that was if I did
decide to try to use them what was the technology back in 1990? Were
the aids frequency compensated or were they just a plain flat response
amplifier? I don't know if the answer I received was bullshit or not
but in any case it was not a positive one. Does anyone know the answer
to this?

I'm semi retired now so I do have some time to fart around with
something like this if I had the appropriate information. According to
the test, I need to make up 55DB at 3.0 and 4.0 KHZ.
I really wouldn't mind carrying a box in my shirt pocket with an
earphone. Any help with such a project would be most sincerely
appreciated. Lenny

55DB is a LOT.
I think your biggest issues are gonna be AGC and compression
so you stay within the P-P output range of your amp...and what's
left of your ears.
Don't think that a linear amp is gonna be satisfactory.

Shouldn't be too hard to simulate. Plug the microphone
and earplug into your sound card.
Google should find you a program that can filter the sound.

 

[Michael A. Terrell]

klem kedidelhopper wrote:

I have known that my hearing has been getting worse over the last few
years.

I'd like to add a note here: Any honorably discharged US military
Veteran should be able to get a hearing aid from the VA at little or no
cost.


--
You can't have a sense of humor, if you have no sense.

 

[Jeff Liebermann]

On Wed, 22 Feb 2012 14:16:12 -0500, "Michael A. Terrell"
<mike.terrell@earthlink.net> wrote:

I'd like to add a note here: Any honorably discharged US military
Veteran should be able to get a hearing aid from the VA at little or no
cost.

I'm not so sure. I think it has to be a service related disability to
qualify, not just age related:
<http://www.ncrar.research.va.gov/forvets/documents/CanIgetaHearingaidfromVA.pdf>
<http://www.hadit.com/forums/index.php?/topic/1407-018-does-va-provide-hearing-aids-and-eyeglasses/>
Still, it's worth a try.

--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

 

[Jeff Liebermann]

On Wed, 22 Feb 2012 07:07:16 -0800 (PST), klem kedidelhopper
<captainvideo462009@gmail.com> wrote:

I may be oversimplifying this a bit but it seems to me that if the
amplifier had a response curve which was the inverse of my hearing
curve, (similar to an RIAA or NAB equalized curve) then the amplifier
would "pre compensate" for my deficiency.

Correct. It will. I don't know much about hearing aids except that
they're expensive. When an impoverished friend volunteered me to
build for her a hearing aid, I started to learn fast. We decided that
the in-the-ear and behind-the-ear variety were mostly made for
convenience and appearance. A comfortable pair of earphones would be
sufficient for most purposes. I collected some assorted electret
microphones, an assortment of earphones, and an Alesis stereo
equalizer. Something like this but older:
<http://www.alesis.com/deq230>
The plan was for her to play some music, talk radio, and recorded
conversations through her hi-fi, while adjusting the equalizer, and
trying various combinations of mic and earphone.

Well, that was the plan. The first thing I discovered was that she
needed about a 30dB dynamic range to cover all the important
frequencies. Small earphones were horrible. Earphones that screwed
in the ear were best, but she didn't like those. I settled on a pair
of Sennheiser over the hear headphones.

The mic had a similar problem. Electret mics pickup all kinds of odd
garbage when near appliances, computers, transformers, etc. The are
also somewhat omni directional, which means they pickup unwanted
background noise. I crafted a directional mic, and applied a
300-4000Hz filter. Never mind the music.

The graphic equalizer curve looked very much like her hearing
sensitivity graph. Both ears turned out to be roughly the same, so I
setup both channels in series to get enough adjustment range to deal
with her approx 30dB loss. I also tried and discarded a compressor,
which only brought up the background noise level.

I then build a rather oversized amplifier, with the proper frequency
and gain curves. It worked fairly well at meetings, quiet
conversations, TV, radio, and telephone. It didn't work so well in
areas where there was considerable background noise or echo, such as
bus stations, in crowds, shopping centers, and near roadways.

Bottom line is that it can be done, but you'll need to make some
compromises and concessions, such as the physical size.

One other option is this: I have my fathers old hearing aids. He
passed away in 1993. I found his old test, and his response curves
were very similar to mine. These are naturally much larger units than
what's available today and although they're not a perfect fit, they
do fit, and could I suppose be used. I am also told that new molds
could be made and they could be "refitted" to my ear shape if I so
desire as well.

Good luck. The local audiologist claimed that it was against
California law to recycle hearing aids. I never verified this. Note
that it's also illegal to sell throw-away (non-replaceable battery)
type hearing aids such as SongBird:
<http://www.songbirdhearing.com>

I'm semi retired now so I do have some time to fart around with
something like this if I had the appropriate information. According to
the test, I need to make up 55DB at 3.0 and 4.0 KHZ.

Ouch. You'll never make it. 55dB of gain between a mic and a nearby
speaker is going to create a feedback problem. If you can isolate the
mic from the speaker, you might have a chance. Note that a normal
hearing response is NOT flat, and that you may not need to fully
compensate. Also, if you can live with just voice, and ignore music,
a frequency response that quits at 3KHz should be sufficient. That's
what you get on a telephone.

I really wouldn't mind carrying a box in my shirt pocket with an
earphone. Any help with such a project would be most sincerely
appreciated. Lenny

The one I built had a rubber ducky toy on top of the headset band,
with the mic inside. Besides being cute, it also decoupled the
mechanical vibrations from the mic.

I'll see if I can find the docs and photos. However, I suspect
they're gone as the relative pillaged everything from her apartment
when she died. I didn't keep copies.

--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

 

[Jeff Liebermann]

On Wed, 22 Feb 2012 12:21:12 -0800, Jeff Liebermann <jeffl@cruzio.com>
wrote:

I'm semi retired now so I do have some time to fart around with
something like this if I had the appropriate information. According to
the test, I need to make up 55DB at 3.0 and 4.0 KHZ.

Also, you might consider doing this digitally, with a DSP development
system. Digitize the mic audio as early as possible. Then you can
filter, limit, noise limit, and tweak the curve quite easily. You can
also Bode shift the frequency slightly (i.e. about 1Hz) to prevent
feedback.

(From 1991, but still interesting).
<http://www.digital-recordings.com/publ/pubaids.html>

Student thesis on the design. Might be a good start.
<http://ucesp.ws.binghamton.edu/~xli/old/research/ed_dha.html>

Google for "dsp hearing aid development".

--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

 

[Wild_Bill]

Not too many years ago (maybe 4-5), I found some cheap hearing "amplifiers"
or similarly labeled devices in a Dollar General store (maybe $5-10).

These weren't sophisticated obviously, but something similar could be used
for a basic building/experimenting sample.
They were made in a similar overall appearance to those older
behind-the-ear, tapered, little curved box.. which also held a couple of 357
type batteries and had a tube that had a tip which fit into the ear canal
opening.

Upon inspection, they turned out to be just another looky-like another
product that the Chinese are so famously known for.
The reason I say this (again) is because there weren't even any holes in the
plastic directly in front of the microphone.
So, I drilled some holes, and they did amplify sounds (nearly all sounds)..
but probably not very useful, in general, to someone with hearing loss.

I mention them because they may be useful as a building block for a more
sophisticated amp system, even if the sophisticated DSP or other circuitry
may not fit in the little behind-the-ear housing (utilizing maybe a separate
thin enclosure clipped to collar or clothing.

I built a hobby grade pocket-type hearing amp kit in the 60s, and the
trouble with having the mic in the pocket is that the noise of the shirt
pocket fabric moving over/rubbing against the mic opening is also amplified.

So.. unless someone has a Jamaican hair style with small braids and beads on
them (don't know the actaul name for that style).. having the mic near the
ear is a much better plan, IMO (may even provide some directional
sensitivity when both ears are using separate devices/amplifiers).

I've never used any Bluetooth devices, so I wouldn't have a clue as to how
useful those types of devices may be, as far as experimenting/modifying for
a practical hearing device.

Some components from cellphone headsets may be useful, but be aware that
those products are generally made with the cheapest components available and
essentially no quality checks.. the cables are fragile and very easily
damaged by normal use (basically throw-away products, like most other
inexpensive gear these days).

--
Cheers,
WB
..............


"klem kedidelhopper" <captainvideo462009@gmail.com> wrote in message
news:c08e795a-a943-4f2b-9e0a-fa940d019502@gr6g2000vbb.googlegroups.com...

I have known that my hearing has been getting worse over the last few
years. I recently had a hearing test to confirm this and compared it
to a similar test which was done 8 years ago. This confirmed my
suspicions. According to the most recent results my speech frequencies
are down about 30 DB more than previously noted. And I'm pretty
certain that 8.0KHZ and above is even worse. The tinitus also tends
exacerbate the problems further.

The test was rather interesting and informative and not unpleasant,
until that is the examiner switched into "salesman" mode. I realize
that these new aids have many new bells and whistles many that I will
never use. In any case, to make a long story shorter, 4000.00 is not
within my budget at this time. Unfortunately there is no money at this
time for anything.

So I would like to ask, (and I've tried to pursue this before) but
unsuccessfully is there any information on the DIY construction of a
pocket unit with an earphone which has either a high pass filter
circuit which rolls off the low frequencies, or a graphic equalizer
that can be set for the frequency response desired?

I may be oversimplifying this a bit but it seems to me that if the
amplifier had a response curve which was the inverse of my hearing
curve, (similar to an RIAA or NAB equalized curve) then the amplifier
would "pre compensate" for my deficiency.

I have found some circuits on the net but they don't seem to be
frequency compensated. Amplifying the entire spectrum would be counter
productive. Perhaps I could try coupling a full range amplifier using
a very small capacitor on the input to roll off the lows.

One other option is this: I have my fathers old hearing aids. He
passed away in 1993. I found his old test, and his response curves
were very similar to mine. These are naturally much larger units than
what's available today and although they're not a perfect fit, they
do fit, and could I suppose be used. I am also told that new molds
could be made and they could be "refitted" to my ear shape if I so
desire as well.

I asked the "salesman" a hypothetical question. And that was if I did
decide to try to use them what was the technology back in 1990? Were
the aids frequency compensated or were they just a plain flat response
amplifier? I don't know if the answer I received was bullshit or not
but in any case it was not a positive one. Does anyone know the answer
to this?

I'm semi retired now so I do have some time to fart around with
something like this if I had the appropriate information. According to
the test, I need to make up 55DB at 3.0 and 4.0 KHZ.
I really wouldn't mind carrying a box in my shirt pocket with an
earphone. Any help with such a project would be most sincerely
appreciated. Lenny

 

[Robert Macy]

On Feb 22, 12:51 pm, Jeff Liebermann <je...@cruzio.com> wrote:

On Wed, 22 Feb 2012 14:16:12 -0500, "Michael A. Terrell"

mike.terr...@earthlink.net> wrote:
  I'd like to add a note here:  Any honorably discharged US military
Veteran should be able to get a hearing aid from the VA at little or no
cost.

I'm not so sure.  I think it has to be a service related disability to
qualify, not just age related:
http://www.ncrar.research.va.gov/forvets/documents/CanIgetaHearingaid...
http://www.hadit.com/forums/index.php?/topic/1407-018-does-va-provide...
Still, it's worth a try.

--
Jeff Liebermann     je...@cruzio.com
150 Felker St #D    http://www.LearnByDestroying.com
Santa Cruz CA 95060http://802.11junk.com
Skype: JeffLiebermann     AE6KS    831-336-2558

A friend of mine, who while in the military spent years in the Engne
room and as a result lost his hearing at all the bearing frequencies -
he had 'holes' in his hearing. Don't know why, but even when he asked;
he was never compensated, nor outfitted for any correction
electronics. He was essentially told, tough. His lack of feedback
while he talked was impressive. As he talked to you, he was so loud
that you felt like a cartoon character with your hair straight back
form the blast.

ex-Hearing Aid employees told me that the ear is a really unusual
organ. They said that there are more nerves going FROM the brain to
the ear than there are nerves going from the ear TO the brain.
Something about the way the ear works, has a lot of muscles that
tighten those hairs etc. Seems people hear more from what it takes to
'adjust' those muscles than from just the vibration sensation alone.

 

[amdx]

On 2/22/2012 9:07 AM, klem kedidelhopper wrote:

I have known that my hearing has been getting worse over the last few
years. I recently had a hearing test to confirm this and compared it
to a similar test which was done 8 years ago. This confirmed my
suspicions. According to the most recent results my speech frequencies
are down about 30 DB more than previously noted. And I'm pretty
certain that 8.0KHZ and above is even worse. The tinitus also tends
exacerbate the problems further.

Just thought I'd post a few cheap hearing devices.

Here's a top 10 list.
http://www.hearingaidamplifier.com/

This one has pretty good Amazon Ratings,
http://www.amazon.com/Sonic-Super-Personal-Sound-Amplifier/dp/B000X2H8G4/ref=cm_cr_pr_sims_t
And big enough to make some filter mods.

and then some more,

http://www.ecrater.com/p/11672984/behind-the-ear-bte-digital

https://www.buymicroplus.com/?mid=1285988&gclid=COqtqqD8sq4CFY2b7Qod7jhmSw

http://www.cabelas.com/hearing-protection-enhancement-ultra-ear-deluxe-hearing-amplifier.shtml?WT.tsrc=CSE&WT.mc_id=GoogleBaseUSA&WT.z_mc_id1=707987&rid=40&mr:trackingCode=DC0FDE51-F5D2-DF11-82EF-001B21631C34&mr:referralID=NA

http://www.safehomeproducts.com/shp2/product/superears-powerful-hearing-amplifier-se4000/hearing-assisting-devices/1531/1531.aspx?source=GoogleBase

http://www.google.com/products/catalog?hl=en&client=firefox-a&rls=org.mozilla:en-USfficial&q=cheap+hearing+amplifier&revid=1765515941&bav=on.2,or.r_gc.r_pw.r_qf.,cf.osb&biw=1047&bih=458&um=1&ie=UTF-8&tbm=shop&cid=15902122760358688880&sa=X&ei=p5lFT4T9CseJgwe95NWYBA&ved=0CIABEPMCMAM

 

[Michael A. Terrell]

Jeff Liebermann wrote:

On Wed, 22 Feb 2012 14:16:12 -0500, "Michael A. Terrell"
mike.terrell@earthlink.net> wrote:

I'd like to add a note here: Any honorably discharged US military
Veteran should be able to get a hearing aid from the VA at little or no
cost.

I'm not so sure. I think it has to be a service related disability to
qualify, not just age related:
http://www.ncrar.research.va.gov/forvets/documents/CanIgetaHearingaidfromVA.pdf
http://www.hadit.com/forums/index.php?/topic/1407-018-does-va-provide-hearing-aids-and-eyeglasses/
Still, it's worth a try.

It depends more on your income. I know a lot of Veterans with
hearing aids and not all are disabled. Military retirees fall under
'Tricare For Life', but are still served by the VA medical system and I
know veterans who get hearing aids & the batteries from the VA. the
local VA clinic has a full time hearing aid tech in the Prosthetics
department. The first step is to dig out your DD214 or other discharge
papers and apply for a VA medical card, if you qualify. The application
form is on the http:www.va.gov website. or you can go to any 'Veteran's
Service Officer' for the form and help to fill it out. You can request a
replacement DD214 from the records office, if needed.

Start here to see if you are eligible for VA care:

<http://www.va.gov/healtheligibility/Library/Tools/Quick_Eligibility_Check/index.asp>

To apply, go here:

https://www.1010ez.med.va.gov/sec/vha/1010ez/

You can download the form and fill it out from here:

<https://www.1010ez.med.va.gov/sec/vha/1010ez/Form/1010EZR-fillable.pdf>

Then you mail it to your closest VA clinic.



You can use this form to request a replacement DD214 or other
discharge papers. You can also request your entire military file, or
any part you need.

<http://www.archives.gov/research/order/standard-form-180.pdf>


--
You can't have a sense of humor, if you have no sense.

 

[Michael A. Terrell]

Jeff Liebermann wrote:

On Wed, 22 Feb 2012 07:07:16 -0800 (PST), klem kedidelhopper
captainvideo462009@gmail.com> wrote:

I may be oversimplifying this a bit but it seems to me that if the
amplifier had a response curve which was the inverse of my hearing
curve, (similar to an RIAA or NAB equalized curve) then the amplifier
would "pre compensate" for my deficiency.

Correct. It will. I don't know much about hearing aids except that
they're expensive. When an impoverished friend volunteered me to
build for her a hearing aid, I started to learn fast. We decided that
the in-the-ear and behind-the-ear variety were mostly made for
convenience and appearance. A comfortable pair of earphones would be
sufficient for most purposes. I collected some assorted electret
microphones, an assortment of earphones, and an Alesis stereo
equalizer. Something like this but older:
http://www.alesis.com/deq230
The plan was for her to play some music, talk radio, and recorded
conversations through her hi-fi, while adjusting the equalizer, and
trying various combinations of mic and earphone.

Well, that was the plan. The first thing I discovered was that she
needed about a 30dB dynamic range to cover all the important
frequencies. Small earphones were horrible. Earphones that screwed
in the ear were best, but she didn't like those. I settled on a pair
of Sennheiser over the hear headphones.

The mic had a similar problem. Electret mics pickup all kinds of odd
garbage when near appliances, computers, transformers, etc. The are
also somewhat omni directional, which means they pickup unwanted
background noise. I crafted a directional mic, and applied a
300-4000Hz filter. Never mind the music.

The graphic equalizer curve looked very much like her hearing
sensitivity graph. Both ears turned out to be roughly the same, so I
setup both channels in series to get enough adjustment range to deal
with her approx 30dB loss. I also tried and discarded a compressor,
which only brought up the background noise level.

I then build a rather oversized amplifier, with the proper frequency
and gain curves. It worked fairly well at meetings, quiet
conversations, TV, radio, and telephone. It didn't work so well in
areas where there was considerable background noise or echo, such as
bus stations, in crowds, shopping centers, and near roadways.

Bottom line is that it can be done, but you'll need to make some
compromises and concessions, such as the physical size.

One other option is this: I have my fathers old hearing aids. He
passed away in 1993. I found his old test, and his response curves
were very similar to mine. These are naturally much larger units than
what's available today and although they're not a perfect fit, they
do fit, and could I suppose be used. I am also told that new molds
could be made and they could be "refitted" to my ear shape if I so
desire as well.

Good luck. The local audiologist claimed that it was against
California law to recycle hearing aids. I never verified this. Note
that it's also illegal to sell throw-away (non-replaceable battery)
type hearing aids such as SongBird:
http://www.songbirdhearing.com

I'm semi retired now so I do have some time to fart around with
something like this if I had the appropriate information. According to
the test, I need to make up 55DB at 3.0 and 4.0 KHZ.

Ouch. You'll never make it. 55dB of gain between a mic and a nearby
speaker is going to create a feedback problem. If you can isolate the
mic from the speaker, you might have a chance. Note that a normal
hearing response is NOT flat, and that you may not need to fully
compensate. Also, if you can live with just voice, and ignore music,
a frequency response that quits at 3KHz should be sufficient. That's
what you get on a telephone.

I really wouldn't mind carrying a box in my shirt pocket with an
earphone. Any help with such a project would be most sincerely
appreciated. Lenny

The one I built had a rubber ducky toy on top of the headset band,
with the mic inside. Besides being cute, it also decoupled the
mechanical vibrations from the mic.

I'll see if I can find the docs and photos. However, I suspect
they're gone as the relative pillaged everything from her apartment
when she died. I didn't keep copies.

How about $12.99 for one from HF?

<http://www.harborfreight.com/ultra-ear-sound-amplifier-66577.html>


--
You can't have a sense of humor, if you have no sense.

 

[Michael A. Terrell]

"hrhofmann@att.net" wrote:

I would recommend the OP start with the HF aids and see if they help,
it's almost worth the price just for the 3 included batteries<G>.

You can get 6 LR44 at Dollar Tree for a dollar. The SR44 are the
expensive version.


--
You can't have a sense of humor, if you have no sense.

 

[hrhofmann@att.net]

On Feb 23, 12:20 am, "Michael A. Terrell" <mike.terr...@earthlink.net>
wrote:

Jeff Liebermann wrote:

On Wed, 22 Feb 2012 07:07:16 -0800 (PST), klem kedidelhopper
captainvideo462...@gmail.com> wrote:

I may be oversimplifying this a bit but it seems to me that if the
amplifier had a response curve which was the inverse of my hearing
curve, (similar to an RIAA or NAB equalized curve) then the amplifier
would  "pre compensate" for my deficiency.

Correct.  It will.  I don't know much about hearing aids except that
they're expensive.  When an impoverished friend volunteered me to
build for her a hearing aid, I started to learn fast.  We decided that
the in-the-ear and behind-the-ear variety were mostly made for
convenience and appearance.  A comfortable pair of earphones would be
sufficient for most purposes.  I collected some assorted electret
microphones, an assortment of earphones, and an Alesis stereo
equalizer.  Something like this but older:
http://www.alesis.com/deq230
The plan was for her to play some music, talk radio, and recorded
conversations through her hi-fi, while adjusting the equalizer, and
trying various combinations of mic and earphone.

Well, that was the plan.  The first thing I discovered was that she
needed about a 30dB dynamic range to cover all the important
frequencies.  Small earphones were horrible.  Earphones that screwed
in the ear were best, but she didn't like those.  I settled on a pair
of Sennheiser over the hear headphones.

The mic had a similar problem.  Electret mics pickup all kinds of odd
garbage when near appliances, computers, transformers, etc.  The are
also somewhat omni directional, which means they pickup unwanted
background noise.  I crafted a directional mic, and applied a
300-4000Hz filter.  Never mind the music.

The graphic equalizer curve looked very much like her hearing
sensitivity graph.  Both ears turned out to be roughly the same, so I
setup both channels in series to get enough adjustment range to deal
with her approx 30dB loss.  I also tried and discarded a compressor,
which only brought up the background noise level.

I then build a rather oversized amplifier, with the proper frequency
and gain curves.  It worked fairly well at meetings, quiet
conversations, TV, radio, and telephone.  It didn't work so well in
areas where there was considerable background noise or echo, such as
bus stations, in crowds, shopping centers, and near roadways.

Bottom line is that it can be done, but you'll need to make some
compromises and concessions, such as the physical size.

One other option is this: I have my fathers old hearing aids. He
passed away in 1993. I found his old test, and his response curves
were very similar to mine. These are naturally much larger units than
what's available today and although they're not a perfect fit,  they
do fit, and could I suppose be used. I am also told that new molds
could be made and they could be "refitted" to my ear shape if I so
desire as well.

Good luck.  The local audiologist claimed that it was against
California law to recycle hearing aids.  I never verified this.  Note
that it's also illegal to sell throw-away (non-replaceable battery)
type hearing aids such as SongBird:
http://www.songbirdhearing.com

I'm semi retired now so I do have some time to fart around with
something like this if I had the appropriate information. According to
the test, I need to make up 55DB at 3.0 and 4.0 KHZ.

Ouch.  You'll never make it.  55dB of gain between a mic and a nearby
speaker is going to create a feedback problem.  If you can isolate the
mic from the speaker, you might have a chance.  Note that a normal
hearing response is NOT flat, and that you may not need to fully
compensate.  Also, if you can live with just voice, and ignore music,
a frequency response that quits at 3KHz should be sufficient.  That's
what you get on a telephone.

I really wouldn't mind carrying a box in my shirt pocket with an
earphone. Any help with such a project would be most sincerely
appreciated.  Lenny

The one I built had a rubber ducky toy on top of the headset band,
with the mic inside.  Besides being cute, it also decoupled the
mechanical vibrations from the mic.

I'll see if I can find the docs and photos.  However, I suspect
they're gone as the relative pillaged everything from her apartment
when she died.  I didn't keep copies.

   How about $12.99 for one from HF?

http://www.harborfreight.com/ultra-ear-sound-amplifier-66577.html

--
You can't have a sense of humor, if you have no sense.- Hide quoted text -

- Show quoted text -

I would recommend the OP start with the HF aids and see if they help,
it's almost worth the price just for the 3 included batteries<G>.

 

[Jeff Liebermann]

On Thu, 23 Feb 2012 11:43:46 -0500, "Michael A. Terrell"
<mike.terrell@earthlink.net> wrote:

You can get 6 LR44 at Dollar Tree for a dollar. The SR44 are the
expensive version.

Expensive? I got tired of overpaying for button batteries and decided
to stock up. I was shocked at how cheap they were from China:
<http://www.ebay.com/itm/150707034161>
50 batteries for about $3.00 including shipping.

I bought both SR44 (silver-oxide) and LR44 (alkaline) cells. For
micrometers and instruments, the SR44 batteries maintains a higher
voltage over a longer time than the LR44.


--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

 

[Jeff Liebermann]

On Wed, 22 Feb 2012 19:57:29 -0600, amdx <amdx@knology.net> wrote:

This one has pretty good Amazon Ratings,
http://www.amazon.com/Sonic-Super-Personal-Sound-Amplifier/dp/B000X2H8G4/ref=cm_cr_pr_sims_t
And big enough to make some filter mods.

That would be a good start, but probably won't work. The mic is
omnidirectional and will tend to pickup undesired noise from odd
directions. The mic really needs to be somewhat directional. The
human brain does a great job of "tuning out" background noises and
distractions. However, when using a hearing aid, that mechanism fails
when dealing with mono amplification:
<http://en.wikipedia.org/wiki/Cocktail_party_effect>

I don't think there's enough space inside to build much more than a
few stages of analog filtering. I used a passive filter approximation
that required three small pot cores connected to the amplifier output.
I didn't want the filter introducing any additional noise, which was
what happened when I filtered at the mic input. It also had the
advantage of literally plugging in between the amplifier and the
earphone, which allowed me to juggle amps along with mics and ep's.
However, with 55dB of expected range, the amplifier will not have
enough headroom to produce any usable output, and will probably clip
badly. Still the claimed 50dB gain might be enough to make it work
adequately.

--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

 

[Michael A. Terrell]

Jeff Liebermann wrote:

On Thu, 23 Feb 2012 11:43:46 -0500, "Michael A. Terrell"
mike.terrell@earthlink.net> wrote:

You can get 6 LR44 at Dollar Tree for a dollar. The SR44 are the
expensive version.

Expensive? I got tired of overpaying for button batteries and decided
to stock up. I was shocked at how cheap they were from China:
http://www.ebay.com/itm/150707034161
50 batteries for about $3.00 including shipping.

I bought both SR44 (silver-oxide) and LR44 (alkaline) cells. For
micrometers and instruments, the SR44 batteries maintains a higher
voltage over a longer time than the LR44.

That's great if you can use all of them before they go bad. I've
replaced two LR44s in the last 18 months. China is days or weeks for
delivery. Dollar Tree is next to one of the grocery stores I use. i can
have them in about five minutes if I run out, or when what's left of a
card die.


--
You can't have a sense of humor, if you have no sense.

 

[Jeff Liebermann]

On Thu, 23 Feb 2012 13:06:22 -0500, "Michael A. Terrell"
<mike.terrell@earthlink.net> wrote:

Jeff Liebermann wrote:

On Thu, 23 Feb 2012 11:43:46 -0500, "Michael A. Terrell"
mike.terrell@earthlink.net> wrote:

You can get 6 LR44 at Dollar Tree for a dollar. The SR44 are the
expensive version.

Expensive? I got tired of overpaying for button batteries and decided
to stock up. I was shocked at how cheap they were from China:
http://www.ebay.com/itm/150707034161
50 batteries for about $3.00 including shipping.

I bought both SR44 (silver-oxide) and LR44 (alkaline) cells. For
micrometers and instruments, the SR44 batteries maintains a higher
voltage over a longer time than the LR44.

That's great if you can use all of them before they go bad. I've
replaced two LR44s in the last 18 months. China is days or weeks for
delivery. Dollar Tree is next to one of the grocery stores I use. i can
have them in about five minutes if I run out, or when what's left of a
card die.

My guess is that I'll consume about 20 per year, mostly in small
flashlights, remotes, keyfobs, etc. I gave away a mess of them to
various friends. I think I have about 80 of each in the fridge.

<http://www.davehylands.com/Machinist/Caliper-Batteries/>
He notes that the self discharge rate is not signifigant. Maybe not.

<http://www.lr44buttonbattery.com/lr44-button-battery-vs-sr44-battery/>
The LR44 has a shelf life of about 10 years. Silver-oxide has a 5
year shelf life:
<http://www.sr44.com>

--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

 

[Michael A. Terrell]

Jeff Liebermann wrote:

My guess is that I'll consume about 20 per year, mostly in small
flashlights, remotes, keyfobs, etc. I gave away a mess of them to
various friends. I think I have about 80 of each in the fridge.

http://www.davehylands.com/Machinist/Caliper-Batteries/
He notes that the self discharge rate is not signifigant. Maybe not.

http://www.lr44buttonbattery.com/lr44-button-battery-vs-sr44-battery/
The LR44 has a shelf life of about 10 years. Silver-oxide has a 5
year shelf life:
http://www.sr44.com

Even with those numbers, I'm better off buying a half dozen at a
time. Unless my health improves to were I can spend more than an hour
or two a week in my shop.


--
You can't have a sense of humor, if you have no sense.