Is 4kHz too high a beeper frequency?

[Don Kuenz]

John Robertson <spam@flippers.com> wrote:

On 2020/04/19 11:37 a.m., Winfield Hill wrote:
piglet wrote...

On 19/04/2020 6:53 pm, Winfield Hill wrote:
I'm finishing a design for a small instrument
that will be used by people of all ages, mostly
in the health-care industry. It's got 115 SMT
parts, so I've spent extra time struggling to
chose the smallest practical part choices. It
has a beeper. The CUI CSS-0578 is smaller than
most, only 5x5mm, but it wants to run at 4 kHz.
Is that going to be hard, or even impossible,
to hear for some users?

Almost everyone should be able to hear it but for
some it will be so high pitched or faint that they
may not recognize it as something important.

Can you buzz it on and off at 300-400Hz?

Yes, will that help enough? We'll be driving it with
a microcontroller, so we can wobble frequency, or do
almost anything. Hmm, will I be able to hear it? OK,
asked my phone to make 4kHz, high but I hear it fine.
Maybe I'd better place several choices on the prototype
PCB, which won't be laid out for minimum overall size.



Have you thought of asking the health care people who would likely be
using this tool what sort of notification they want?

In many cases there are a great many devices beeping and booping all
around them, so if this is a life-saving device I would perhaps want to
have it also strobe some sort of light to really catch one's attention
in a possibly noisy environment.

My job takes me into Operating Rooms. And now that you mention it,
although ECG beeps are distinctly heard when a patient's first
anesthetized, its hard for me to recall if the ECG beeps persist and
fade into background noise or if they stop altogether.
My attention's usually focused elsewhere. And some surgeons play
music during procedures. None of which helps me hear any ECG beeps that
may be present.

There was an interesting case of a church office with weird warbling
which was hard to isolate. Two phone guys examined their system and came
up empty handed. Then the younger of the two used a smartphone app that
matched the warble to a similar sound in an online database to identify
its source.
It turns out that an old medical device was replaced, set aside, and
forgotten. Eventually its batteries ran low and it warbled for
replacements.

Then there's that horrific clarion of a battery backup in need of
service. That gets under my skin, guaranteed, every time.

You certainly must hear some unusual sounds that emanate from coin-op
arcade machines.

Thank you,

--
Don Kuenz KB7RPU
There was a young lady named Bright Whose speed was far faster than light;
She set out one day In a relative way And returned on the previous night.

 

[Don Kuenz]

John Robertson <spam@flippers.com> wrote:

On 2020/04/19 11:37 a.m., Winfield Hill wrote:
piglet wrote...

On 19/04/2020 6:53 pm, Winfield Hill wrote:
I'm finishing a design for a small instrument
that will be used by people of all ages, mostly
in the health-care industry. It's got 115 SMT
parts, so I've spent extra time struggling to
chose the smallest practical part choices. It
has a beeper. The CUI CSS-0578 is smaller than
most, only 5x5mm, but it wants to run at 4 kHz.
Is that going to be hard, or even impossible,
to hear for some users?

Almost everyone should be able to hear it but for
some it will be so high pitched or faint that they
may not recognize it as something important.

Can you buzz it on and off at 300-400Hz?

Yes, will that help enough? We'll be driving it with
a microcontroller, so we can wobble frequency, or do
almost anything. Hmm, will I be able to hear it? OK,
asked my phone to make 4kHz, high but I hear it fine.
Maybe I'd better place several choices on the prototype
PCB, which won't be laid out for minimum overall size.



Have you thought of asking the health care people who would likely be
using this tool what sort of notification they want?

In many cases there are a great many devices beeping and booping all
around them, so if this is a life-saving device I would perhaps want to
have it also strobe some sort of light to really catch one's attention
in a possibly noisy environment.

My job takes me into Operating Rooms. And now that you mention it,
although ECG beeps are distinctly heard when a patient's first
anesthetized, its hard for me to recall if the ECG beeps persist and
fade into background noise or if they stop altogether.
My attention's usually focused elsewhere. And some surgeons play
music during procedures. None of which helps me hear any ECG beeps that
may be present.
Upon further reflection, the ECG beeps are always present. When you
clearly hear them over the phone you psychologically brace yourself for
OR troubles. It's interesting though, how they tend to fade into the
background when you're onsite in an OR.

There was an interesting case of a church office with weird warbling
which was hard to isolate. Two phone guys examined their system and came
up empty handed. Then the younger of the two used a smartphone app that
matched the warble to a similar sound in an online database to identify
its source.
It turns out that an old medical device was replaced, set aside, and
forgotten. Eventually its batteries ran low and it warbled for
replacements.

Then there's that horrific clarion of a battery backup in need of
service. That gets under my skin, guaranteed, every time.

You certainly must hear some unusual sounds that emanate from coin-op
arcade machines.

Thank you,

--
Don Kuenz KB7RPU
There was a young lady named Bright Whose speed was far faster than light;
She set out one day In a relative way And returned on the previous night.

 

[Winfield Hill]

Don Kuenz wrote...

Then there's that horrific clarion of a battery backup
in need of service. That gets under my skin, guaranteed,
every time.

Sheesh! Last night at 2 am one of our Kidde smoke alarms
started honking loudly twice every 30 seconds. I stumbled
around in the dark, trying to find the one was responsible.
Figured it was beeping for a new 9V battery, once a year,
even though they run on 120Vac - ggrrr! They all showed a
tell-tale green light, saying I'm OK. But I was looking at
one when it beeped, and saw a red LED flash. Turned out it
was a combo smoke/CO unit, claiming end-of-life, 10 years,
even though it was only 7 years old. Gggrrr!! Rotate it
off the bracket, pull out the power plug, get it down, and
remove the battery. Sheesh! finally, some peace and quiet.
Calm down, back to bed. Damn those Kidde engineers.


--
Thanks,
- Win

 

[Joe Gwinn]

On 19 Apr 2020 10:53:38 -0700, Winfield Hill <winfieldhill@yahoo.com>
wrote:

I'm finishing a design for a small instrument
that will be used by people of all ages, mostly
in the health-care industry. It's got 115 SMT
parts, so I've spent extra time struggling to
chose the smallest practical part choices. It
has a beeper. The CUI CSS-0578 is smaller than
most, only 5x5mm, but it wants to run at 4 kHz.
Is that going to be hard, or even impossible,
to hear for some users?

You need some harmonics to make the beeper localizable. We use the
increasing loss of higher harmonics with distance to estimate
distance.

If you drive a low duty cycle pulse train into a small speaker, you
will get a harmonic series that the ear will complete, yielding what
appears to be a lower pitch (at the pulse rate) than any of the
harmonics actually transmitted.

..<https://en.wikipedia.org/wiki/Missing_fundamental>

Joe Gwinn

 

[Phil Allison]

Clive Arthur wrote:

--------------------

John Woodgate would likely be an expert in this, but I don't know if
he's still around.

** There are links to John dated 2015 for recent a publication of his on hearing aid loops.

..... Phil

 

[Phil Allison]

DecadentLinux...@decadence.org wrote:

-----------------------------------

I can't hear the standard smoke alarm beeps.

Bill


WTF are you guys old and decrepit?

** I am astonished too - seems there are lots of 80 & 90 year olds lurking here - many with SEVERE hearing loss.

I am 67 and find the sound of my smoke alarm *painfully* loud - and it needs to be to WAKE you up.

FYI:

I can easily hear 10kHz.

My threshold at 4kHz is about 30dB SPL rising to 50dB SPL at 10kHz.

Checked today with a known good meter.



..... Phil

 

[Phil Allison]

Clifford Heath wrote:

========================

The standard smoke alarm frequency is 3100Hz.

It's important that the alarm should wake most people, including partly
deaf ones. So that frequency is a good bet.

** Yes, it is the ear's most sensitive frequency.

However it's also the most easily damaged by exposure to high SPLs so the first to go.

There are a number of reasons for picking a high frequency - including the inherent echo in most rooms with bare walls. Frequencies in the range of 2 to 4kHz do bounce around a lot.


..... Phil



hil

 

[Robert Baer]

Cursitor Doom wrote:

On Sun, 19 Apr 2020 10:53:38 -0700, Winfield Hill wrote:

I'm finishing a design for a small instrument
that will be used by people of all ages, mostly in the health-care
industry. It's got 115 SMT parts, so I've spent extra time struggling
to chose the smallest practical part choices. It has a beeper. The
CUI CSS-0578 is smaller than most, only 5x5mm, but it wants to run at 4
kHz.
Is that going to be hard, or even impossible, to hear for some users?

On the basis that by the time I'd hit 45, i'd lost everything over 11kHz
I'd say yes, for many it could be a problem.
I wouldn't chance anything over 2kHz IIWY.

Unscientific test using plastic/mylar cone speakers:
1 inch dia: 3.8KC peak loudness, 4.0KC limit.
2.25 inch dia: 2.5KC, "useful" to 3.2KC, reasonable sound to 4KC,
still there at 8KC (broad "peak" 7KC-9KC).

Do not know my hearing top-end is on above tests; ost likely below
the 15KC TV.
After all, i am only over 80 (what is this about 45?).

 

[Cursitor Doom]

On Mon, 20 Apr 2020 17:55:50 -0700, Robert Baer wrote:

Unscientific test using plastic/mylar cone speakers:
1 inch dia: 3.8KC peak loudness, 4.0KC limit.
2.25 inch dia: 2.5KC, "useful" to 3.2KC, reasonable sound to 4KC,
still there at 8KC (broad "peak" 7KC-9KC).

Do not know my hearing top-end is on above tests; ost likely below
the 15KC TV.
After all, i am only over 80 (what is this about 45?).

Robert, everyone's different. It's just a general rule that top end
hearing declines with age and there may be odd rare exceptions to that
rule. If you're one of them, just be grateful!

 

[Andreas Karrer]

* Winfield Hill <winfieldhill@yahoo.com>:

I'm finishing a design for a small instrument
that will be used by people of all ages, mostly
in the health-care industry. It's got 115 SMT
parts, so I've spent extra time struggling to
chose the smallest practical part choices. It
has a beeper. The CUI CSS-0578 is smaller than
most, only 5x5mm, but it wants to run at 4 kHz.
Is that going to be hard, or even impossible,
to hear for some users?

Of course there will be people who don't hear it.

Our oven timer has a beep at g'''' (G7, 3135 Hz), and the volume is
adjustable in three steps. I can hear it at the highest volume setting
when I'm in the same room, but not when I'm in the next room, even when
the door is open or ajar. My sons then shout from upstairs "Pa! It's
beeping! It's ear-splitting!"

Our Braun Thermoscan ear thermometer beeps at h'''' (b7, 3950 Hz) when the
measurement is finished. Of course, it's a faint beep, because the
device is only some 10 cm away from the ear measured and about 30 cm
from the other. I don't hear it; luckily, there is also a LED that
signals the end, so I measure my body temperature in front of a mirror.

I'm 63 and I don't have a hearing aid (probably should have one).

- Andi

 

[Mike Coon]

In article <r7mdk6$ecb$1@dont-email.me>, cd@not4mail.com says...

Robert, everyone's different. It's just a general rule that top end
hearing declines with age and there may be odd rare exceptions to that
rule. If you're one of them, just be grateful!

Our (UK) jazz supremo the late Humphrey Lyttelton (and humorist, writer,
broadcaster, cartoonist, calligrapher, etc etc) said, on learning that
rule, that he could hardly wait!

Mike.

 

[Bill Gill]

On 4/20/2020 6:38 PM, Phil Allison wrote:

DecadentLinux...@decadence.org wrote:

-----------------------------------

I can't hear the standard smoke alarm beeps.

Bill


WTF are you guys old and decrepit?


** I am astonished too - seems there are lots of 80 & 90 year olds lurking here - many with SEVERE hearing loss.

I am 67 and find the sound of my smoke alarm *painfully* loud - and it needs to be to WAKE you up.

FYI:

I can easily hear 10kHz.

My threshold at 4kHz is about 30dB SPL rising to 50dB SPL at 10kHz.

Checked today with a known good meter.



.... Phil

Yes there are many people who cannot hear the beeper in a
smoke detector. They make smoke detectors with a voice
alarm and that is what I have.

Bill

 

Bill Gill <billnews2@cox.net> wrote in
news:r7mr8r$bb4$1@dont-email.me:

On 4/20/2020 6:38 PM, Phil Allison wrote:
DecadentLinux...@decadence.org wrote:

-----------------------------------

I can't hear the standard smoke alarm beeps.

Bill


WTF are you guys old and decrepit?


** I am astonished too - seems there are lots of 80 & 90 year
olds lurking here - many with SEVERE hearing loss.

I am 67 and find the sound of my smoke alarm *painfully* loud -
and it needs to be to WAKE you up.

FYI:

I can easily hear 10kHz.

My threshold at 4kHz is about 30dB SPL rising to 50dB SPL at
10kHz.

Checked today with a known good meter.



.... Phil







Yes there are many people who cannot hear the beeper in a
smoke detector. They make smoke detectors with a voice
alarm and that is what I have.

Bill

I'd pump it through my stereo... or get a nice 'tick box'
(shocker) and 'connect' (to myself) that when I lay down to sleep.
Guaranteed to wake you faster than a smoke alarm. It is essentially
a single, hot tick from a tazer driver (toned down a bit). All
depends on where you decide to attach it.

It says WAKE UP! to wherever you decide to 'attach' it. Hook it
to your alarm clock or your smoke alarm. Do not hook it to your
nuts.

Having trouble getting that dumb 30 year old child of yours out of
the house? Get him "up for work" using this a couple times! Use the
'multiple-tick' setting. Definitely *near* the groin. He'll move
out real quick.

Thinking of other means or have a bad rodent problem? Use it to
light off your rodent eradication explosive devices.

 

[Phil Allison]

Andreas Karrer wrote:

--------------------

Our oven timer has a beep at g'''' (G7, 3135 Hz), and the volume is
adjustable in three steps. I can hear it at the highest volume setting
when I'm in the same room, but not when I'm in the next room, even when
the door is open or ajar. My sons then shout from upstairs "Pa! It's
beeping! It's ear-splitting!"

I'm 63 and I don't have a hearing aid (probably should have one).

** You have a serious hearing loss, maybe due to exposure to loud noise for years. Get it checked out soon.




...... Phil

 

[Phil Allison]

Bill Gill wrote:

--------------------

-----------------------------------

I can't hear the standard smoke alarm beeps.

Bill


WTF are you guys old and decrepit?


** I am astonished too - seems there are lots of 80 & 90 year olds lurking here - many with SEVERE hearing loss.

I am 67 and find the sound of my smoke alarm *painfully* loud - and it needs to be to WAKE you up.

FYI:

I can easily hear 10kHz.

My threshold at 4kHz is about 30dB SPL rising to 50dB SPL at 10kHz.


Yes there are many people who cannot hear the beeper in a
smoke detector.

** Only those with severe hearing loss.

They make smoke detectors with a voice
alarm and that is what I have.

** Good.

Most kids up to age 13 are not woken by regular smoke alarms, even in the same room and need an alarm like yours. A completely different issue though.


..... Phil

 

[amdx]

On 4/20/2020 3:05 PM, Winfield Hill wrote:

Don Kuenz wrote...

Then there's that horrific clarion of a battery backup
in need of service. That gets under my skin, guaranteed,
every time.

Sheesh! Last night at 2 am one of our Kidde smoke alarms
started honking loudly twice every 30 seconds. I stumbled
around in the dark, trying to find the one was responsible.
Figured it was beeping for a new 9V battery, once a year,
even though they run on 120Vac - ggrrr! They all showed a
tell-tale green light, saying I'm OK. But I was looking at
one when it beeped, and saw a red LED flash. Turned out it
was a combo smoke/CO unit, claiming end-of-life, 10 years,
even though it was only 7 years old. Gggrrr!! Rotate it
off the bracket, pull out the power plug, get it down, and
remove the battery. Sheesh! finally, some peace and quiet.
Calm down, back to bed. Damn those Kidde engineers.

If you are competing with other enunciates, why not something unique,
Three descending tones 3k 2.5k and 2k and repeat. Or the same, plus a
ramping freq back up from 2k to 3k, then repeat.

Mikek

 

[boB]

On Sun, 19 Apr 2020 22:13:52 -0400, bitrex <user@example.net> wrote:

On 4/19/2020 10:06 PM, boB wrote:
On Sun, 19 Apr 2020 14:17:39 -0500, amdx <nojunk@knology.net> wrote:

On 4/19/2020 12:53 PM, Winfield Hill wrote:
I'm finishing a design for a small instrument
that will be used by people of all ages, mostly
in the health-care industry. It's got 115 SMT
parts, so I've spent extra time struggling to
chose the smallest practical part choices. It
has a beeper. The CUI CSS-0578 is smaller than
most, only 5x5mm, but it wants to run at 4 kHz.
Is that going to be hard, or even impossible,
to hear for some users?


My hearing rolls off prety quick right at 4kHz.
I had a friend working on my computer and the beeper was
beeping, and ask him why and he said he could hear it.
It is much lower than 4kHz.
He had the memory in the wrong slots, that what caused the beeper to
sound.
Mikek


Some have nulls in their hearing spectrum and some, their HF response
just rolls off like Mikek's. If it is not a piezo beeper, you could
have two tones at once or alternating to make sure it is nticeable.

I think that around 3kHz is the most sensitive pitch for most people.

Also, lower frequencies, say, below 500 Hz are going to take a larger
transducer and higher power.


a square at say 500 Hz and square at 2000 Hz (four octaves up)
ring-modulated to give it some sums and differences and a "metallic"
edge to cover the frequency bases more thoroughly

Yeah... Square wave or something with harmonics would help too.

 

[boB]

On Sun, 19 Apr 2020 20:52:01 -0700 (PDT), Ricky C
<gnuarm.deletethisbit@gmail.com> wrote:

On Sunday, April 19, 2020 at 10:06:53 PM UTC-4, boB wrote:
On Sun, 19 Apr 2020 14:17:39 -0500, amdx <nojunk@knology.net> wrote:

On 4/19/2020 12:53 PM, Winfield Hill wrote:
I'm finishing a design for a small instrument
that will be used by people of all ages, mostly
in the health-care industry. It's got 115 SMT
parts, so I've spent extra time struggling to
chose the smallest practical part choices. It
has a beeper. The CUI CSS-0578 is smaller than
most, only 5x5mm, but it wants to run at 4 kHz.
Is that going to be hard, or even impossible,
to hear for some users?


My hearing rolls off prety quick right at 4kHz.
I had a friend working on my computer and the beeper was
beeping, and ask him why and he said he could hear it.
It is much lower than 4kHz.
He had the memory in the wrong slots, that what caused the beeper to
sound.
Mikek


Some have nulls in their hearing spectrum and some, their HF response
just rolls off like Mikek's. If it is not a piezo beeper, you could
have two tones at once or alternating to make sure it is nticeable.

I think that around 3kHz is the most sensitive pitch for most people.

Also, lower frequencies, say, below 500 Hz are going to take a larger
transducer and higher power.

No, just a lower resonance which can be done via acoustic coupling or mechanical coupling. A little bit of thought to the packaging can probably half that frequency and produce more volume from less energy.

Right. Lower resonance means large transducer but the ear is not as
sensitive here so higher power too, to have the same loudness as a
higher frequency... But not TOO high of frequency.

Also, larger diaphragm or transducer usually means more mass so higher
power. This is one reason that sub-woofes require more power than
the mid and high satellite speakers.

Good old Phil from Australia would even know this but I have him kill
filed so hopefully wouldn't see his response except through someone
copying.

 

[Phil Allison]

booB strikes again !!

=======================

Right. Lower resonance means large transducer but the ear is not as
sensitive here so higher power too, to have the same loudness as a
higher frequency... But not TOO high of frequency.

Also, larger diaphragm or transducer usually means more mass so higher
power.

** Utter bollocks.

The increased moving area *more* than compensate for the extra mass.

This is one reason that sub-woofes require more power than
the mid and high satellite speakers.

** Oh dear - "wall to wall thinking" when one mistake generates a host of of others to back it up.

The "sensitivity" of woofers is much the same as for mids and tweeters.

Typical numbers are around 90dB /watt /metre in each case.

Good old Phil from Australia would even know this

** Well no.

I do not know this cos it ain't true.

Who would ever believe a Boob, anyway ?


...... Phil

 

[Ricky C]

On Tuesday, April 21, 2020 at 7:22:20 PM UTC-4, boB wrote:

On Sun, 19 Apr 2020 20:52:01 -0700 (PDT), Ricky C
gnuarm.deletethisbit@gmail.com> wrote:

On Sunday, April 19, 2020 at 10:06:53 PM UTC-4, boB wrote:
On Sun, 19 Apr 2020 14:17:39 -0500, amdx <nojunk@knology.net> wrote:

On 4/19/2020 12:53 PM, Winfield Hill wrote:
I'm finishing a design for a small instrument
that will be used by people of all ages, mostly
in the health-care industry. It's got 115 SMT
parts, so I've spent extra time struggling to
chose the smallest practical part choices. It
has a beeper. The CUI CSS-0578 is smaller than
most, only 5x5mm, but it wants to run at 4 kHz.
Is that going to be hard, or even impossible,
to hear for some users?


My hearing rolls off prety quick right at 4kHz.
I had a friend working on my computer and the beeper was
beeping, and ask him why and he said he could hear it.
It is much lower than 4kHz.
He had the memory in the wrong slots, that what caused the beeper to
sound.
Mikek


Some have nulls in their hearing spectrum and some, their HF response
just rolls off like Mikek's. If it is not a piezo beeper, you could
have two tones at once or alternating to make sure it is nticeable.

I think that around 3kHz is the most sensitive pitch for most people.

Also, lower frequencies, say, below 500 Hz are going to take a larger
transducer and higher power.

No, just a lower resonance which can be done via acoustic coupling or mechanical coupling. A little bit of thought to the packaging can probably half that frequency and produce more volume from less energy.


Right. Lower resonance means large transducer but the ear is not as
sensitive here so higher power too, to have the same loudness as a
higher frequency... But not TOO high of frequency.

Also, larger diaphragm or transducer usually means more mass so higher
power. This is one reason that sub-woofes require more power than
the mid and high satellite speakers.

That depends entirely on the details. A piezo chirper has very poor coupling to the air. The acoustic or mechanical coupling can be done in a way that makes the coupling more efficient giving more volume for the same power.

Doesn't matter. Win has given no indication of being interested in designing a speaker cabinet. He obviously is more comfortable with electronic design.

Good old Phil from Australia would even know this but I have him kill
filed so hopefully wouldn't see his response except through someone
copying.

I'll likely be the brunt of his missive and I will be replying if he does, so you can read all about it if you wish.

--

Rick C.

-+- Get 1,000 miles of free Supercharging
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