Speakers for High Frequency Sound

G

Guest

Guest
Archived from groups: rec.audio.pro,sci.electronics.design,sci.med (More info?)

Some people can hear an extremely high-pitched sound generated by
television CRTs and television cameras. I have long wondered what
frequency this sound is. So, I am looking around for test equipment to
help me measure it. I plan to use an audio generator (which I can buy
for about $200), but I need to find a set of headphones that can
produce sound at these high frequencies. The low end frequency should
be about 12 kHz, and I would like to be able to go at least to 50 kHz.
I am guessing the sound is somewhere around 40 kHz.

Incidentally, I just got my hearing checked by my ENT (Ear, Nose,
Throat doctor). I measured in the 5-to-10 dB range on both the eardrum
and nerve conduction tests across the entire measured frequency range
(up to 8 kHz for eardrum, 12 kHz for nerve conduction). My doctor said
that they want to see values less than 20 dB, so I am well-within the
safe zone, as far as they are concerned. However, one reason that she
scheduled this test for me is that I complained that I am going deaf in
one of my ears. I have almost completely lost my sensitivity to the
ultra-high pitched sound in that ear. I can hear that sound 100 times
better from my other ear.

People don't realize what a difference it makes to a person's
perception when the range of hearing differs. I can walk into a room
with other people, and they think they are in an empty room. If there
is an operating television in the room, I will be aware of almost
physical contact. Other people can hold a conversation in a normal
voice, but I have to listen over a sound similar to a dentist's drill
or a jet engine. After several minutes of that, I often feel dazed. No
one else even notices anything, except maybe that I am acting a little
more odd than normal.
 
G

Guest

Guest
Archived from groups: rec.audio.pro,sci.electronics.design,sci.med (More info?)

> Some people can hear an extremely high-pitched sound generated by
> television CRTs and television cameras. I have long wondered what
> frequency this sound is.

It's the horizontal scanning frequency, 15,734.25 Hz for American color TV.
Trust me. You don't need to measure it.


> So, I am looking around for test equipment to
> help me measure it. I plan to use an audio generator (which I can buy
> for about $200), but I need to find a set of headphones that can
> produce sound at these high frequencies. The low end frequency should
> be about 12 kHz, and I would like to be able to go at least to 50 kHz.
> I am guessing the sound is somewhere around 40 kHz.

If humans can hear it, it can't possibly be at 40kHz, because the best human
hearing extends to only a bit above 20kHz.
 
G

Guest

Guest
Archived from groups: rec.audio.pro,sci.electronics.design,sci.med (More info?)

> The high pitched sound is usually from the yoke and flyback
transformer
> (actually an inductor) feeding the television's CRT. For most
televisions in the
> United States that frequency is right at 15,734 Hz because the
vertical scan
> rate for NTSC is 29.97 times per second and it draws 525 lines. 29.97
X 525 =
> 15734.25 horzontal scanning frequency.

That sounds likely, but I have a few questions about that.

1) Is this same sub-unit on a standard television camera?
2) What exactly is converting the electrical energy into sound?
3) If this sound is so square in the middle of normal human hearing (16
kHz is well-within the range of normal human hearing), why have I met
so few people who can hear it?

Question 3 is perplexing, because my sister and I were always the only
people in our classroom or in someone's home who could hear the
television.

One time, when my sister was hospitalized, her nurse tried to turn on
the television set for her, but the set did not appear to turn on. The
nurse was about to leave the room for help with the TV, when my sister
told him that the TV had just turned on. The screen was still black, so
he did not know what to think. Then, the TV slowly produced a picture.
My sister could tell the set was on because she could hear it. No one
else in the room at the time could hear it.

I have worked in a computer call center for several years. At one time,
we had CRT monitors in the room with us. I was the only person who
could hear them. I liked to turn the CRTs off when not in use, because
they hurt my ears. One time, I walked up to two of my associates and
asked them if they would mind if I turned off the CRTs. One of them
already knew I could hear the CRTs, but the other one did not. The one
who did not know was surprised. Naturally, he reached up and turned off
the set, and asked if I could hear the difference. Then, he turned it
on. Then, off. Then, on. The other associate, who understood what I was
experiencing, began to laugh, and called the guy a sadist.

> I hear it loudly enough that I can tell when someone walks around in
an
> adjacent room with a television set on.

Yes, that is what this is like. When I walk down the sidewalk, I can
hear the television inside the homes I pass. I can tell if someone
comes between the television and me, even if they are inside a closed
room.

I was at a hospital recently. As I walked across the lobby, I heard a
television. I looked around. Then, I noticed a television camera inside
a security enclosure box, mostly hidden in the ceiling. It took me a
little longer to find it than it used to, because I had to locate it
with just one ear (as I said, I am mostly deaf in the other ear, now).
 

Mike

Distinguished
Apr 1, 2004
975
0
18,930
Archived from groups: rec.audio.pro,sci.electronics.design,sci.med (More info?)

pooua@aol.com wrote:
> Some people can hear an extremely high-pitched sound generated by
> television CRTs and television cameras. I have long wondered what
> frequency this sound is. So, I am looking around for test equipment to
> help me measure it. I plan to use an audio generator (which I can buy
> for about $200), but I need to find a set of headphones that can
> produce sound at these high frequencies. The low end frequency should
> be about 12 kHz, and I would like to be able to go at least to 50 kHz.
> I am guessing the sound is somewhere around 40 kHz.
>
> Incidentally, I just got my hearing checked by my ENT (Ear, Nose,
> Throat doctor). I measured in the 5-to-10 dB range on both the eardrum
> and nerve conduction tests across the entire measured frequency range
> (up to 8 kHz for eardrum, 12 kHz for nerve conduction). My doctor said
> that they want to see values less than 20 dB, so I am well-within the
> safe zone, as far as they are concerned. However, one reason that she
> scheduled this test for me is that I complained that I am going deaf in
> one of my ears. I have almost completely lost my sensitivity to the
> ultra-high pitched sound in that ear. I can hear that sound 100 times
> better from my other ear.
>
> People don't realize what a difference it makes to a person's
> perception when the range of hearing differs. I can walk into a room
> with other people, and they think they are in an empty room. If there
> is an operating television in the room, I will be aware of almost
> physical contact. Other people can hold a conversation in a normal
> voice, but I have to listen over a sound similar to a dentist's drill
> or a jet engine. After several minutes of that, I often feel dazed. No
> one else even notices anything, except maybe that I am acting a little
> more odd than normal.
>

Your objective is not clear. If you're gonna measure your own hearing...

How much trouble/expense do you want to expend to measure something you
can't fix?

How useful is a random measurement using unknown/uncalibrated equipment?
I did some experiments 30 years ago trying to measure frequency response
of speakers, rooms, etc. I NEVER got repeatable measurements at high
frequencies...not even close.

One might have the tendency to crank up the level until you can hear
something. That might not be the best thing to do. No need to destroy
what hearing you have left.
YMMV.
mike

--
Return address is VALID.
Wanted, PCMCIA SCSI Card for HP m820 CDRW.
FS 500MHz Tek DSOscilloscope TDS540 Make Offer
http://nm7u.tripod.com/homepage/te.html
Wanted, 12.1" LCD for Gateway Solo 5300. Samsung LT121SU-121
Bunch of stuff For Sale and Wanted at the link below.
http://www.geocities.com/SiliconValley/Monitor/4710/
 
G

Guest

Guest
Archived from groups: rec.audio.pro,sci.electronics.design,sci.med (More info?)

> It's the horizontal scanning frequency, 15,734.25 Hz for American
> color TV. Trust me. You don't need to measure it.

I need to measure it, to be certain that is what I am hearing.

> If humans can hear it, it can't possibly be at 40kHz, because
> the best human hearing extends to only a bit above 20kHz.

I think you are assuming some things that aren't necessarily so. One
very important assumption you are making that is likely to be wrong is
that no human can hear very much above 20 kHz. There are a number of
ways that assumption could be wrong. In any event, there is no physical
mechanism that would prevent a human from hearing higher frequencies.

Even so, I probably exaggerated the frequency of the sound. I estimate
that the pitch is about double the highest frequency that I heard in
the sound booth at the ENT. The highest frequency they tested was 12
kHz, so I should estimate the sound I hear from a television as 24 kHz.
It's an ear-piercing shriek, in any event.

I can also hear LCD screens, but that's at a lower pitch, I think, and
they are much quieter. I first noticed it when I was in a nature park.
It was very quiet outside, so as I raised my digital camera up to take
a picture, I could distinctly hear the LCD screen.

Now I am taking a college class in a room that has 3 television sets
suspended from the ceiling. One man saw me putting earplugs in my ears,
and asked if I could hear the televisions. It turned out that he is
able to hear some televisions (the one in his college dorm), but he
could not hear the televisions in the classroom. As far as I can tell,
I am the only person in the room who hears those televisions.
 
G

Guest

Guest
Archived from groups: rec.audio.pro,sci.electronics.design,sci.med (More info?)

> my hearing is down 30 dB at 8 K(as high as the test at AES went)
> when compared to 3K and I can easily hear it

Did AES test your nerve conduction? I have a suspicion that the sound I
hear is not coming through my eardrums. I am beginning to suspect that
I hear it through my skull, which means nerve conduction.

Your eardrum may not be able to hear so well, but maybe your ear nerves
are still able to pick up sounds normally?
 
G

Guest

Guest
Archived from groups: rec.audio.pro,sci.electronics.design,sci.med (More info?)

My objectives are to find out what frequencies I can hear, and to match
one of the calibrated frequencies from the signal generator against the
sound I hear from televisions, so that I can finally know what that
frequency from the television is.

I am certain that just about any commercial audio signal generator is
going to be callibrated well enough to distinguish the frequency I
hear. It isn't that difficult to make a stable signal (particularly in
commercial test equipment, which is what the signal generator is).

As for how much I would spend, well, I can justify some of the expense
because I am an electronics hobbiest. So, I don't mind buying a $200
piece of test equipment as much as I might otherwise. And, I am going
deaf, so I don't have forever to make this test.

But, this is nothing. I would spend over a thousand dollars to test
some of the other things about myself that I want to test. In
particular, I can generate a sensation like electricity throughout my
body, at will. I don't know what that is, but I would like to find out.
As in, I would spend a thousand dollars to find out.
 
G

Guest

Guest
Archived from groups: rec.audio.pro,sci.electronics.design,sci.med (More info?)

pooua@aol.com wrote:
> > The high pitched sound is usually from the yoke and flyback
> transformer
> > (actually an inductor) feeding the television's CRT. For most
> televisions in the
> > United States that frequency is right at 15,734 Hz because the
> vertical scan
> > rate for NTSC is 29.97 times per second and it draws 525 lines.
29.97
> X 525 =
> > 15734.25 horzontal scanning frequency.
>
> That sounds likely, but I have a few questions about that.
>
> 1) Is this same sub-unit on a standard television camera?
> 2) What exactly is converting the electrical energy into sound?
> 3) If this sound is so square in the middle of normal human hearing
(16
> kHz is well-within the range of normal human hearing), why have I met
> so few people who can hear it?
>
16 kHz is not square in the middle. When you become an 'old fart' you
will find that out. 16K is your top octave which you will lose as you
age. Sorry, I don't like it either but I actually don't miss hearing
the Horizontal. Been working in commmercial TV for 28 years and haven't
heard the H in more than 10.
GG
 
G

Guest

Guest
Archived from groups: rec.audio.pro,sci.electronics.design,sci.med (More info?)

> >I think you are assuming some things that aren't necessarily so. One
> >very important assumption you are making that is likely to be wrong
is
> >that no human can hear very much above 20 kHz. There are a number of
> >ways that assumption could be wrong. In any event, there is no
physical
> >mechanism that would prevent a human from hearing higher
frequencies.

---
> Yes, there is. The mass of the tympanic membrane and the
> sensitivity of the cochlear cilia.

The tympanic membrane (the eardrum) can be bypassed; it is not
absolutely essential in every case for hearing (indeed, there are
hearing aids that do exactly that).

I don't know of a way around the cochlear cilia, short of replacing it
with a functional equivalent (in contrast, the function of the tympanic
membrane is not absolutely essential to hearing). But, what are the
limits of the cochlear cilia? Certainly there are animals that can hear
higher frequencies, and they use the same basic equipment as humans do.


> I've done work trying to determine whether the nonlinearity of the
> auditory system will allow beat notes which occur as a result of
> exposure to the ear of ultrasonic signals which should result in
> heterodynes being generated which can be heard, are heard and, so
far,
> the results have been negative. That is, if the ear is exposed to a
> pair of frequencies, both of which are frequencies higher than can be
> heard, the beat note won't be heard either.

That is interesting in its own way, but I don't believe that is
directly applicable in this case. The sensitive person may not be
hearing a beat note.
---

> >Even so, I probably exaggerated the frequency of the sound. I
estimate
> >that the pitch is about double the highest frequency that I heard in
> >the sound booth at the ENT. The highest frequency they tested was 12
> >kHz, so I should estimate the sound I hear from a television as 24
kHz.
> >It's an ear-piercing shriek, in any event.

---
> Unless you have perfect pitch, your estimates as to the frequency of
> what you heard are close to meaningless.

All the more reason to set up a test and measure it directly. I hate
this guesswork.

---

> >I can also hear LCD screens, but that's at a lower pitch, I think,
and
> >they are much quieter. I first noticed it when I was in a nature
park.
> >It was very quiet outside, so as I raised my digital camera up to
take
> >a picture, I could distinctly hear the LCD screen.

---
> you may have crosstalk between your vision and auditory systems.

I suppose you would need to run a test to find out for certain?
---

> >Now I am taking a college class in a room that has 3 television sets
> >suspended from the ceiling. One man saw me putting earplugs in my
ears,
> >and asked if I could hear the televisions. It turned out that he is
> >able to hear some televisions (the one in his college dorm), but he
> >could not hear the televisions in the classroom. As far as I can
tell,
> >I am the only person in the room who hears those televisions.

---
> It might be instructive to determine whether you can "hear" the
> monitors with your eyes closed.

I absolutely could hear the monitors with my eyes closed. I would be
able to hear them in a pitch-dark room. I have been looking down at my
desk when the instructor has turned them on from his control console,
and I can definitely hear them when he turns them on. The sound of the
televisions is distinct and loud, particular in my good ear. As I say,
I wear earplugs in class to manage the sound.
 
G

Guest

Guest
Archived from groups: rec.audio.pro,sci.electronics.design,sci.med (More info?)

They should have tested you with more than just headphones. The
headphones measure eardrum response. The nerve conduction test is done
through the skull. When they tested me for nerve conduction, I wore a
loop with a mass at either end (I did not get a good look at it). One
end was placed ahead of my left ear a few inches, and the other end was
behind my right ear an inch or two.

The difference is important, because eardrum hearing loss may be
reversible or correctible. Nerve hearing loss is not. Also, the
different types of hearing loss use different types of hearing aides.
There are other differences, too, but I don't know what they all are.
My doctor told me that they looked for my nerve conduction to match my
ear conduction pretty closely.
 
G

Guest

Guest
Archived from groups: rec.audio.pro,sci.electronics.design,sci.med (More info?)

I am getting "Connection refused" when I attempt to go to that URL.
 
G

Guest

Guest
Archived from groups: rec.audio.pro,sci.electronics.design,sci.med (More info?)

<pooua@aol.com> wrote in message
news:1108165220.798267.223400@c13g2000cwb.googlegroups.com...
> Some people can hear an extremely high-pitched sound generated by
> television CRTs and television cameras. I have long wondered what
> frequency this sound is. So, I am looking around for test equipment to
> help me measure it. I plan to use an audio generator (which I can buy
> for about $200), but I need to find a set of headphones that can
> produce sound at these high frequencies. The low end frequency should
> be about 12 kHz, and I would like to be able to go at least to 50 kHz.
> I am guessing the sound is somewhere around 40 kHz.

The high pitched sound is usually from the yoke and flyback transformer
(actually an inductor) feeding the television's CRT. For most televisions in the
United States that frequency is right at 15,734 Hz because the vertical scan
rate for NTSC is 29.97 times per second and it draws 525 lines. 29.97 X 525 =
15734.25 horzontal scanning frequency.

Old black and white televisions were slightly higher: 30 Hz vertical X 525 lines
= 15,750 Hz.

I hear it loudly enough that I can tell when someone walks around in an adjacent
room with a television set on.

John LeBlanc
houston, TX
 
G

Guest

Guest
Archived from groups: rec.audio.pro,sci.electronics.design,sci.med (More info?)

On 11 Feb 2005 15:40:20 -0800, the renowned pooua@aol.com wrote:

>Some people can hear an extremely high-pitched sound generated by
>television CRTs and television cameras. I have long wondered what
>frequency this sound is.

No need to measure it. In the US & Canada (and other NTSC countries
such as Taiwan) the high-pitched sound that you can hear is either
15.75kHz (rare these days) or 15.734264kHz. That's when the TV is
locked to a broadcast. If it's on an empty channel, the frequency will
be a bit different.

> So, I am looking around for test equipment to
>help me measure it. I plan to use an audio generator (which I can buy
>for about $200), but I need to find a set of headphones that can
>produce sound at these heigh frequencies. The low end frequency should
>be about 12 kHz, and I would like to be able to go at least to 50 kHz.
>I am guessing the sound is somewhere around 40 kHz.
>
>Incidentally, I just got my hearing checked by my ENT (Ear, Nose,
>Throat doctor). I measured in the 5-to-10 dB range on both the eardrum
>and nerve conduction tests across the entire measured frequency range
>(up to 8 kHz for eardrum, 12 kHz for nerve conduction). My doctor said
>that they want to see values less than 20 dB, so I am well-within the
>safe zone, as far as they are concerned. However, one reason that she
>scheduled this test for me is that I complained that I am going deaf in
>one of my ears. I have almost completely lost my sensitivity to the
>ultra-high pitched sound in that ear. I can hear that sound 100 times
>better from my other ear.
>
>People don't realize what a difference it makes to a person's
>perception when the range of hearing differs. I can walk into a room
>with other people, and they think they are in an empty room. If there
>is an operating television in the room, I will be aware of almost
>physical contact. Other people can hold a conversation in a normal
>voice, but I have to listen over a sound similar to a dentist's drill
>or a jet engine. After several minutes of that, I often feel dazed. No
>one else even notices anything, except maybe that I am acting a little
>more odd than normal.

When I was about 12 years old, I got into a trade show with my Dad
where they had a demo of an ultrasonic welder. It just about took my
head off when they turned it on, but none of the old farts could hear
a thing. I'm now older than he was then. 8-( I can still hear the
racket from a NTSC TV but it's not nearly as loud.


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
speff@interlog.com Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com
 
G

Guest

Guest
Archived from groups: rec.audio.pro,sci.electronics.design,sci.med (More info?)

On 11 Feb 2005 16:52:14 -0800, pooua@aol.com wrote:

>> It's the horizontal scanning frequency, 15,734.25 Hz for American
>> color TV. Trust me. You don't need to measure it.
>
>I need to measure it, to be certain that is what I am hearing.
>
>> If humans can hear it, it can't possibly be at 40kHz, because
>> the best human hearing extends to only a bit above 20kHz.
>
>I think you are assuming some things that aren't necessarily so. One
>very important assumption you are making that is likely to be wrong is
>that no human can hear very much above 20 kHz. There are a number of
>ways that assumption could be wrong. In any event, there is no physical
>mechanism that would prevent a human from hearing higher frequencies.

---
Yes, there is. The mass of the tympanic membrane and the sensitivity
of the cochlear cilia.

I've done work trying to determine whether the nonlinearity of the
auditory system will allow beat notes which occur as a result of
exposure to the ear of ultrasonic signals which should result in
heterodynes being generated which can be heard, are heard and, so far,
the results have been negative. That is, if the ear is exposed to a
pair of frequencies, both of which are frequencies higher than can be
heard, the beat note won't be heard either.
---

>Even so, I probably exaggerated the frequency of the sound. I estimate
>that the pitch is about double the highest frequency that I heard in
>the sound booth at the ENT. The highest frequency they tested was 12
>kHz, so I should estimate the sound I hear from a television as 24 kHz.
>It's an ear-piercing shriek, in any event.

---
Unless you have perfect pitch, your estimates as to the frequency of
what you heard are close to meaningless.
---

>I can also hear LCD screens, but that's at a lower pitch, I think, and
>they are much quieter. I first noticed it when I was in a nature park.
>It was very quiet outside, so as I raised my digital camera up to take
>a picture, I could distinctly hear the LCD screen.

---
you may have crosstalk between your vision and auditory systems.
---

>Now I am taking a college class in a room that has 3 television sets
>suspended from the ceiling. One man saw me putting earplugs in my ears,
>and asked if I could hear the televisions. It turned out that he is
>able to hear some televisions (the one in his college dorm), but he
>could not hear the televisions in the classroom. As far as I can tell,
>I am the only person in the room who hears those televisions.

---
It might be instructive to determine whether you can "hear" the
monitors with your eyes closed.

--
John Fields
 
G

Guest

Guest
Archived from groups: rec.audio.pro,sci.electronics.design,sci.med (More info?)

<pooua@aol.com> wrote:
>Some people can hear an extremely high-pitched sound generated by
>television CRTs and television cameras. I have long wondered what
>frequency this sound is. So, I am looking around for test equipment to
>help me measure it. I plan to use an audio generator (which I can buy
>for about $200), but I need to find a set of headphones that can
>produce sound at these high frequencies. The low end frequency should
>be about 12 kHz, and I would like to be able to go at least to 50 kHz.
>I am guessing the sound is somewhere around 40 kHz.

Why not just do a google search for "NTSC video sweep frequency?"
Hint: it's around 17 KHz.

>Incidentally, I just got my hearing checked by my ENT (Ear, Nose,
>Throat doctor). I measured in the 5-to-10 dB range on both the eardrum
>and nerve conduction tests across the entire measured frequency range
>(up to 8 kHz for eardrum, 12 kHz for nerve conduction). My doctor said
>that they want to see values less than 20 dB, so I am well-within the
>safe zone, as far as they are concerned. However, one reason that she
>scheduled this test for me is that I complained that I am going deaf in
>one of my ears. I have almost completely lost my sensitivity to the
>ultra-high pitched sound in that ear. I can hear that sound 100 times
>better from my other ear.

Right, but most places cannot test that high accurately enough. I think
the House Institute in LA can do up to 16 KHz accurately.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."
 
G

Guest

Guest
Archived from groups: rec.audio.pro,sci.electronics.design,sci.med (More info?)

In article <1108168896.929130.108230@f14g2000cwb.googlegroups.com>,
<pooua@aol.com> wrote:
>That sounds likely, but I have a few questions about that.
>
>1) Is this same sub-unit on a standard television camera?

Surely on vidicon tube cameras, which also have a yoke.

>2) What exactly is converting the electrical energy into sound?

Mostly it's the magnetic field from the yoke vibrating things around, but
to some extent it's also microphonic effects in electrolytic capacitors.
Potting the yoke reduces most of it, though.

>3) If this sound is so square in the middle of normal human hearing (16
>kHz is well-within the range of normal human hearing), why have I met
>so few people who can hear it?

Because too many people today have poor hearing from living in a very
loud environment. Try asking some children.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."
 
G

Guest

Guest
Archived from groups: rec.audio.pro,sci.electronics.design,sci.med (More info?)

> > In any event, there is no
> > physical mechanism that would prevent a human from hearing higher
> > frequencies.

> Sure there is. [snip] Basically, you run out of structure at some
point
> in this part of the ear, and the extent and health of this structure
sets
> the highest frequencies that you can perceive.

That would mean there is an upper limit. It does not at all tell us
that no one could hear higher frequencies than 20 kHz.
 
G

Guest

Guest
Archived from groups: rec.audio.pro,sci.electronics.design,sci.med (More info?)

> In another post, you mentioned having to focus on a
> particular conversation or a particular flute.

I think you have me confused with someone else. I haven't said anything
in this thread about focusing on a particular sound or conversation or
flute.
 
G

Guest

Guest
Archived from groups: rec.audio.pro,sci.electronics.design,sci.med (More info?)

> 8k was as high as the test measured so I am not aware of my
> measured abilities above that

I asked the tech who administered my hearing test last week what the
highest frequency is that the machine could test. I watched as she
touched the buttons on the control panel, and I saw the machine display
the frequency on the monitor. The machine tests a maximum of 8 kHz for
the eardrum, but it tests up to 12 kHz for nerve.
 
G

Guest

Guest
Archived from groups: rec.audio.pro,sci.electronics.design,sci.med (More info?)

> How many of you have heard a high-pitched "sound"
> very much like 15 KHz yoke, even though there is no yoke? This is
> sometimes called "ringing in the ears", and is what I was thinking of
when
> I asked those questions about tinnitus.

Yes, I do have ringing in my ears, but it is fairly quiet. That's one
way I can distinguish it from the sound of the TV. The TV set sounds
very loud, so loud that I can hear it 15 feet away through the walls
and closed windows of buildings, or from about 50 feet away in an open
space.