Bios beeps volume too low to hear.

[John]

This is not so much problem as an annoyance, but could be a problem if and
when a problem does happen.

Computer is home built - Asus P6T SE with the latest Bios installed (0808).
The case is Lian Li PC-K58B and came with a small bud like speaker that
fits direct to the motherboard.
When booting, the one beep that happens on boot up is hardly noticeable, I
need to have my ear next to the case to even hear it. I've changed the bud
speaker to an 57mm cone 8ohm speaker in the hope that this would amplify
the sound but to no avail, still hardly noticeable.
I've checked though the Bios settings to see if the sound is adjustable but
as far as I can ascertain this isn't possible. I've also enclosed the new
cone speaker into a container to see if the volume would improve.
Is there a way I can get around this problem by amplifying the volume of
the speaker? Has anyone else come across this and if so how did you rectify
the situation?

 

[VanguardLH]

This is not so much problem as an annoyance, but could be a problem if and
when a problem does happen.

Computer is home built - Asus P6T SE with the latest Bios installed (0808).
The case is Lian Li PC-K58B and came with a small bud like speaker that
fits direct to the motherboard.
When booting, the one beep that happens on boot up is hardly noticeable, I
need to have my ear next to the case to even hear it. I've changed the bud
speaker to an 57mm cone 8ohm speaker in the hope that this would amplify
the sound but to no avail, still hardly noticeable.
I've checked though the Bios settings to see if the sound is adjustable but
as far as I can ascertain this isn't possible. I've also enclosed the new
cone speaker into a container to see if the volume would improve.
Is there a way I can get around this problem by amplifying the volume of
the speaker? Has anyone else come across this and if so how did you rectify
the situation?

A speaker using a magnetically-driven cone won't work. You need to replace
the defective bud speaker with a piezoelectric speaker. An 8-ohm speaker
won't work. The piezo tweeter has an impedance of several hundreds of ohms
at their typical single-frequency for making beep sounds. Some examples of
piezo button speakers are listed at:

http://search.digikey.com/scripts/DkSearch/dksus.dll?Cat=720966&k=piezo speaker

They carry a lot of electronic parts so you might find a replacement
provided you can some info from the defective part. There are some that
connect to the 4-pin mobo header to which you connect the speaker (if the
mobo doesn't itself have the piezo buzzer), like:

http://www.pcpartscollection.com/mosp.html

If you don't have the 4-pin header (i.e., the buzzer was soldered to the
mobo), you could just clip off the connector, strip the wire ends, solder
the wires to the mobo pads, and use hot-melt glue to hold the speaker bud in
place on the mobo. Or you might find one that solders to the mobo or you
wire it, like:

http://www.radioshack.com/search/index.jsp?kwCatId=&kw=piezo&origkw=piezo&sr=1

 

[John]

A speaker using a magnetically-driven cone won't work. You need to replace
the defective bud speaker with a piezoelectric speaker. An 8-ohm speaker
won't work. The piezo tweeter has an impedance of several hundreds of ohms
at their typical single-frequency for making beep sounds. Some examples of
piezo button speakers are listed at:

http://search.digikey.com/scripts/DkSearch/dksus.dll?Cat=720966&k=piezo speaker

They carry a lot of electronic parts so you might find a replacement
provided you can some info from the defective part. There are some that
connect to the 4-pin mobo header to which you connect the speaker (if the
mobo doesn't itself have the piezo buzzer), like:

http://www.pcpartscollection.com/mosp.html

If you don't have the 4-pin header (i.e., the buzzer was soldered to the
mobo), you could just clip off the connector, strip the wire ends, solder
the wires to the mobo pads, and use hot-melt glue to hold the speaker bud in
place on the mobo. Or you might find one that solders to the mobo or you
wire it, like:

http://www.radioshack.com/search/index.jsp?kwCatId=&kw=piezo&origkw=piezo&sr=1

It hadn't entered my mind that the speaker could be faulty but after
reading your reply it makes sense. I'll need to source a supplier in my
part of the world, of find an one that sells internationally.

Thanks for the information and explanation.

 

[Paul]

A speaker using a magnetically-driven cone won't work.

That is not true. All of my computers here have magnetic speakers
for "PC Beep" and work just fine.

A sample drive circuit for "PC Beep", can be seen here on PDF page 32.

http://www.intel.com/design/chipsets/designex/BXDPDG10.htm

Redrawing the equivalent circuit, it looks like this.

+5V ("VCC")
|
+------>
"SPKR"
+------<
|
34 ohms
|
Logic level ____|/ 2N3904
|\ silicon switching

transistor

|
GND

Maximum power transfer, occurs with a 34 ohm speaker. Maybe they selected
that, to match well with a 32 ohm speaker. They use a cheap pair of
resistors in parallel to handle the maximum power/heat expected
of the circuit (like if you short the speaker terminals).

The logic level signal, lacks the output drive, to drive the magnetic
speaker directly. The 2N3904 can be run as a saturating switch,
handling currents of up to 200mA. If it was operated in linear
mode, it would fry. But saturated, with low Vcesat, even the
physically small transistor they use, is sufficient. You have
to check that the 3904 has sufficient current gain, for the
application.

Even when the circuit isn't perfectly matched, such as using
an 8 ohm speaker in the circuit, if you do the math, the
power level isn't significantly reduced. The speaker is
still getting 0.11 watts or so into 8 ohms.

A piezoelectric can also be used. I have no idea exactly what
the equivalent circuit looks like for one. My experience is,
they like lots of driving voltage, at less current than
a magnetic speaker would use. I've driven my piezo
headphones to high levels, using an opamp circuit.

With regard to testing that circuit for correct operation,
I don't see it being particularly easy for an end-user to
test the '3904 transistor is working properly. If there were
utilities that could force a logic 1 or a logic 0 onto
the base of the '3904, it might be easier to characterize and
verify circuit operation. I can't even be sure, looking at
a motherboard, that I can find those components. They
might be near the PANEL header, or they might not. In
a picture of the P6T, I can see a number of transistors near
the PANEL header. And no suspicious large resistors.

To "amplify" that output, you would need an amplifier. And
the amplifier would likely "click or pop" each time the computer
was turned on. I would use this as a means to get an audio signal.
The ceramic cap is present, for DC isolation. No amplifier
necessarily appreciates DC coming at it. The choice of the
8 ohm resistor (or the nearest standard value close to that),
gives a peak to peak amplitude of about 1 volt, which should be
sufficient to drive a line-level set of amplified computer speakers.
A 1/8" jack could be placed, where it says "to audio amp". You could
connect tip and ring to the upper signal, and sleeve to the ground.
If it still isn't loud enough, change the 8 ohm resistor to 33 ohms.
The set of amplified PC speakers, would then be dedicated to the
"PC beep" function.

+5V ("VCC")
|
+------> --+
|
8 ohm resistor, 1/4 watt or 1/2 watt
|
+--- 0.1uF 25V cap ----> to audio amp
| (assume 10K input
+------< --+ +---> impedance)
| |
34 ohms GND
|
Logic level ____|/ 2N3904
|\ silicon switching

transistor

|
GND

There are other examples of "PC Beep" drive circuits. This one
looks like an emitter follower. See PDF page 74. This would
likely blow your eardrums out. I don't think this one is
safe to short the SPKR terminals, whereas the first circuit above
is short circuit safe.

http://www.intel.com/design/chipsets/schematics/252812.htm

See PDF page 118 here, for another example. This is similar to the
first link, but with a different limiting resistor. This might not
be very loud, but changing the resistor value could fix it. This
might only be about 1/3rd as loud as the first circuit.

http://web.archive.org/web/20061118133939/http://www.winbond.com/PDF/sheet/w83627hf.pdf

Another problem, is figuring out what is driving the logic signal.
I think you can get PC beep from some SuperI/O chips, or
from the Southbridge. There might be more than one potential
source on the motherboard. Trying to trace that circuit, wouldn't
be easy. It would be easy to verify one leg of the SPKR pins
is wired to VCC (+5). But for the other leg, you might have to
ohm around for a while, to find the bit that connects to it, and
then guess at the connected circuit topology.

I checked the vip.asus.com forums, and I don't see a lot of complaints
about problems with PC beep on P6T SE. Some people report they're getting a
beep code, but at the same time, they're not complaining about the
volume level of the beep. It could be, the OPs board has a fault,
like a bad '3904.

HTH,
Paul

 

[Paul]

My guess is that the problem was with a soldered-on button piezo speaker,
not with one connected to a 4-pin mobo header (which will usually take a
magnetically-driven speaker). With an integrated "buzzer", the driving
circuit probably won't handle the current load required for a magnetic
speaker. That's why the OP needs to replace the piezo speaker with another
one.

There is no piezo. Just the white PANEL header in the lower left corner of
this photo. The SPKR pins are on the lower right of the PANEL header.
Four pin spacing (as shown in the manual). Even with this resolution of
picture, it is pretty hard to make anything out, like what might be
driving it.

http://www.unitycorp.co.jp/asus/motherboard/intel/lga1366/p6t_se/big_photo.jpg

Paul

 

[Mike Easter]

VanguardLH wrote:

There is no piezo. Just the white PANEL header in the lower left corner of
this photo. The SPKR pins are on the lower right of the PANEL header.
Four pin spacing (as shown in the manual).

The OP got the buzzer/tweeter with his Lian Li case, it didn't come on
the mobo.

I got a buzzer with a Cooler Master case and it was just what I needed
for the mobo the case was intended for.

I assumed that the 'industry' practices or standards were that the
responsibility for the mobo speaker lay with the case mfr/supplier, like
the little case wired coil speakers of the past, and that the case
people had assumed/ taken on/ the responsibility and decided to save
money with little buzzers to 'stick onto' the mobo.

 

[John]

The OP got the buzzer/tweeter with his Lian Li case, it didn't come on
the mobo.

I got a buzzer with a Cooler Master case and it was just what I needed
for the mobo the case was intended for.

I assumed that the 'industry' practices or standards were that the
responsibility for the mobo speaker lay with the case mfr/supplier, like
the little case wired coil speakers of the past, and that the case
people had assumed/ taken on/ the responsibility and decided to save
money with little buzzers to 'stick onto' the mobo.

Just to clarify the situation the existing buzzer is the same as shown on
the link that Vanguard supplied: http://www.pcpartscollection.com/mosp.html

I managed to source a replacement from an old computer a friend had in his
garage but I'm afraid it made no difference to the volume.

I'm an elderly person with some hearing defect so to check that it wasn't
my hearing I got my wife (who can hear a pin drop at 50 metres) to listen
when I booted up. She remarked that though she could hear the beep it was
faint. I then tried three other computers (friends) to see if the volume
was better or the same as mine, and found that they all had very faint
buzzer beeps. In fact the owners of the other computers were unaware that
computers beeped on boot up and had never noticed a beep when booting the
computer.

I read with interest the points that Paul made, but my expertise is not up
to changing the motherboard circuit wiring. I wonder is it possible to
amplify either a cone speaker or a piezo buzzer, between the motherboard
connection and speaker/piezo?

 

[VanguardLH]

Just to clarify the situation the existing buzzer is the same as shown on
the link that Vanguard supplied: http://www.pcpartscollection.com/mosp.html

I managed to source a replacement from an old computer a friend had in his
garage but I'm afraid it made no difference to the volume.

I'm an elderly person with some hearing defect so to check that it wasn't
my hearing I got my wife (who can hear a pin drop at 50 metres) to listen
when I booted up. She remarked that though she could hear the beep it was
faint. I then tried three other computers (friends) to see if the volume
was better or the same as mine, and found that they all had very faint
buzzer beeps. In fact the owners of the other computers were unaware that
computers beeped on boot up and had never noticed a beep when booting the
computer.

I read with interest the points that Paul made, but my expertise is not up
to changing the motherboard circuit wiring. I wonder is it possible to
amplify either a cone speaker or a piezo buzzer, between the motherboard
connection and speaker/piezo?

The unit that I linked to that showed a 4-pin connector to a bud buzzer
meant you were using the 4-pin mobo header for the speaker connection. That
should handle a *small* 8-ohm speaker. It looks like you have a flaw in the
mobo regarding the driving circuit for the speaker.

Oh well, if you didn't know what the beep counts meant (long beeps, short
beeps, how many of each) then you aren't losing anything important to you
that you could do anything about. Once the OS starts loading and it loads
the audio drivers, your external speakers are going to get used, anyway.

I know some Dells use the externally attached speakers for the warning
buzzer instead of using one like you have. The POST beeps come through the
powered speakers (so obviously you must have them powered to hear the
beeps). I haven't bothered to read the online manual for your particular
motherboard to see what it might support for sound issued through the
backpanel connectors.

 

[Paul]

I wonder is it possible to
amplify either a cone speaker or a piezo buzzer, between the motherboard
connection and speaker/piezo?

Sure. You could take something, like a "portable karaoke"
machine, which has a microphone and a speaker, and hold the
microphone inside the computer. But this will also pick up fan
noise, computer noise, and generally be a bad idea. (You'd need
to build an enclosure around the microphone and speaker, to keep
out other noises.)

You could try contacting Asus support, and see if they even
know their P6T SE is a sub-standard design. Maybe they already
know that some batch of boards, had the wrong value of resistor
stuffed in them, causing the speaker level to be weak.

I think a superior solution, is to rig up a circuit that
connectors to the speaker pins. (Mainly, because the solution
would be "quiet" when the beep interval was finished.) But to
build that, you'll need to be a hobbyist, and have access to parts.
And it doesn't sound like you're really that interested in doing
that. I don't blame you. This should all be unnecessary.

Paul

 

[John]

The unit that I linked to that showed a 4-pin connector to a bud buzzer
meant you were using the 4-pin mobo header for the speaker connection. That
should handle a *small* 8-ohm speaker. It looks like you have a flaw in the
mobo regarding the driving circuit for the speaker.

Oh well, if you didn't know what the beep counts meant (long beeps, short
beeps, how many of each) then you aren't losing anything important to you
that you could do anything about. Once the OS starts loading and it loads
the audio drivers, your external speakers are going to get used, anyway.

I never mentioned anywhere in my messages that implicated I was unaware of
the error beeps, I might not be an expert but I have been building
computers since 1991, but thanks for the interest you've taken with my
small problem.

 

[John]

Sure. You could take something, like a "portable karaoke"
machine, which has a microphone and a speaker, and hold the
microphone inside the computer. But this will also pick up fan
noise, computer noise, and generally be a bad idea. (You'd need
to build an enclosure around the microphone and speaker, to keep
out other noises.)

You could try contacting Asus support, and see if they even
know their P6T SE is a sub-standard design. Maybe they already
know that some batch of boards, had the wrong value of resistor
stuffed in them, causing the speaker level to be weak.

I suspect that this is the problem but can't be hassled returning the
motherboard.

I think a superior solution, is to rig up a circuit that
connectors to the speaker pins. (Mainly, because the solution
would be "quiet" when the beep interval was finished.) But to
build that, you'll need to be a hobbyist, and have access to parts.
And it doesn't sound like you're really that interested in doing
that. I don't blame you. This should all be unnecessary.

Paul

Thanks for the detailed information it's been very interesting.

 

[Paul]

I suspect that this is the problem but can't be hassled returning the
motherboard.

You should at least report it to Asus Tech Support (as difficult
as that could be :-( ). I checked the Asus FAQ page, and don't
see it mentioned there. I doubt they'd add an item, just because
you reported it, but it's a start. (They like to shove real design
problems, "under the carpet". I've never heard a story of them
"doing the right thing", when a design is bad.) If they get enough
complaints, maybe an engineer at Asus will have a look at what was
done. Since they may be making around 4 million motherboards per
month, it is pretty hard to get personal attention from the
company - they're not known for their communication skills.

Any kind of circuit, which could threshold the signal on the
SPKR pin, could be made to drive a speaker. But virtually
any circuit we could think of, would mean a hobbyist style
project. I tried looking for a product that just plugged into
the speaker leads, but didn't find anything, other than the usual
"piezo with wires" thing. I think the assumption is, that is
loud enough.

Paul

 

[John]

You should at least report it to Asus Tech Support (as difficult
as that could be :-( ). I checked the Asus FAQ page, and don't
see it mentioned there. I doubt they'd add an item, just because
you reported it, but it's a start. (They like to shove real design
problems, "under the carpet". I've never heard a story of them
"doing the right thing", when a design is bad.) If they get enough
complaints, maybe an engineer at Asus will have a look at what was
done. Since they may be making around 4 million motherboards per
month, it is pretty hard to get personal attention from the
company - they're not known for their communication skills.

Fair enough, I'll contact them with the problem. I mentioned in a previous
message that I'd tried a few other computers to see if the volume level was
any different than my machine, and found the volume was just as low as my
computer. I'll go back and check the motherboard manufacturer on these
machines and if Asus I'll note the model and report them as well. If there
from a different manufacturer it would indicate that the motherboard
speaker volume isn't counted as a high priority.

Any kind of circuit, which could threshold the signal on the
SPKR pin, could be made to drive a speaker. But virtually
any circuit we could think of, would mean a hobbyist style
project. I tried looking for a product that just plugged into
the speaker leads, but didn't find anything, other than the usual
"piezo with wires" thing. I think the assumption is, that is
loud enough.

Thanks again for all you're help. Though I haven't come across a solution,
the exercise has been very interesting.

 

[Mike Easter]

Though I haven't come across a solution,
the exercise has been very interesting.

How can you be sure that your good-eared wife's report to you, "You're
right, honey, it is very very quiet." wasn't just a matter of spousal
tactful support?

 

[John]

How can you be sure that your good-eared wife's report to you, "You're
right, honey, it is very very quiet." wasn't just a matter of spousal
tactful support?

Well, in our part of the World we don't use the term "Honey" and if you
knew my wife you'd know it's hard getting *tactful* support of any kind
when it comes to me, even after nearly fifty years of marriage (anniversary
tomorrow).

 

[PeeCee]

Just to clarify the situation the existing buzzer is the same as shown on
the link that Vanguard supplied:
http://www.pcpartscollection.com/mosp.html

I managed to source a replacement from an old computer a friend had in his
garage but I'm afraid it made no difference to the volume.

I'm an elderly person with some hearing defect so to check that it wasn't
my hearing I got my wife (who can hear a pin drop at 50 metres) to listen
when I booted up. She remarked that though she could hear the beep it was
faint. I then tried three other computers (friends) to see if the volume
was better or the same as mine, and found that they all had very faint
buzzer beeps. In fact the owners of the other computers were unaware that
computers beeped on boot up and had never noticed a beep when booting the
computer.

I read with interest the points that Paul made, but my expertise is not up
to changing the motherboard circuit wiring. I wonder is it possible to
amplify either a cone speaker or a piezo buzzer, between the motherboard
connection and speaker/piezo?

John

I was recently asked to build a morse key 'sounder' for my local museum.

In the process of creating a suitable sounder I initially experimented with
one of those Piezo beepers commonly used on motherboards.
I found it interesting that the frequency output by the average Piezo
sounder was sufficiently high to make it difficult to hear.
I know from recent hearing tests that my hearing falls away very quickly
over 2 KHZ. (Damage as a result of 35 + years industrial noise)
So the 3KHZ + of these Piezo sounders was way to high to hear unless I put
my hearing aids in.
I suspect this might be the reason you are having difficulty hearing it as
well.

Older PC's using the 8 - 32 ohm speaker and circuit Paul spoke of operated
at a lower frequency from memory, so would have appeared louder to older
ears.

If you feel you 'must' amplify then a simple LM386 audio amplifier kit like
this one:
http://www.jaycar.co.nz/productView.asp?ID=KC5152&CATID=25&form=CAT&SUBCATID=557
capacitively coupled to the beeper output from the motherboard will make
quite a 'loud' beep to a normal 8 ohm speaker.

To be candid though I would not bother trying to mod the motherboard to
amplify the Beeps from your motherboard.
Hacking into the motherboard is not something I would recommend unless you
have good soldering skills/tools and commensurate electronic skills.
Also the only time you really need to hear the beeps is when there is an
error, the normal post POST beep occurs about the time the video appears on
the screen any way.

In an error situation the beep codes will be continuously repeated, and you
can bend down and get nearer to the source to record what they are.

Best
Paul.

 

[John]

If you feel you 'must' amplify then a simple LM386 audio amplifier kit like
this one:
http://www.jaycar.co.nz/productView.asp?ID=KC5152&CATID=25&form=CAT&SUBCATID=557
capacitively coupled to the beeper output from the motherboard will make
quite a 'loud' beep to a normal 8 ohm speaker.

Thanks, I'll try this out.

 

[Paul]

Thanks, I'll try this out.

If you want to try that out, you'll still need a way of wiring it to the
motherboard.

The Molex hard drive connector, has available on it +12V and ground.
So you can pick up power for the amplifier there.

While looking around for a solution, I did run into another one of those,
but it looked like it wouldn't deliver enough power to the speaker,
unless it was running off +12V. So +12V would be a good choice for this
purpose.

If you need crimp pins and a 1x4 plastic connector housing, you can get
them here. Or, a local electronics store may have them (not Radio Shack).
My one good electronics store here, doesn't stock those.

http://www.frontx.com/order_c.html

1x4 to make a "SPKR" cable
http://www.frontx.com/cpx075_3.html

Strip of pins, to populate the 1x4. A single strip of
ten, should be enough to account for mistakes. They're cheap
enough, that you can afford to buy extras.

http://www.frontx.com/cpx076.html

The same crimp pins, might fit over the Jaycar terminals.

To get power for such an amplifier, buy a Molex "Y" cable, with
two 1x4 connectors on one end, and one 1x4 on the other end. If
I need Molex connectors for projects, I cut those up to obtain
male or female power connectors, with the wires on one end already
in place. The wire gauge may be too large to crimp comfortably
in the small pins, but you'll be able to work out something there.

To get a signal for the amp, you still need to install a load
resistor across the SPKR terminals, and then your coupling
capacitor goes on "the end that wiggles".

To insulate the wiring when finished (any exposed wire), look
for "Polyolefin" tubing, otherwise known as shrinkwrap. You
apply a little heat, it shrinks, and grabs whatever is underneath.
Once shrunk, the insulation won't slide off on you. I keep about
five different sizes here. Buy the tubing a bit on the big side,
because if you try for a tight fit, the wire gets caught in it.

You should be careful, to insulate the +12V supply lead. If that
shorts to any exposed ground, "sparks will fly". Wrapping
electrical tape around stuff, may sound like a good idea, until
the day it falls off. Shrink wrap is better than electrical tape,
because it uses no heat-sensitive adhesive.

Paul

 

[John]

If you want to try that out, you'll still need a way of wiring it to the
motherboard.

The Molex hard drive connector, has available on it +12V and ground.
So you can pick up power for the amplifier there.

While looking around for a solution, I did run into another one of those,
but it looked like it wouldn't deliver enough power to the speaker,
unless it was running off +12V. So +12V would be a good choice for this
purpose.

If you need crimp pins and a 1x4 plastic connector housing, you can get
them here. Or, a local electronics store may have them (not Radio Shack).
My one good electronics store here, doesn't stock those.

http://www.frontx.com/order_c.html

1x4 to make a "SPKR" cable
http://www.frontx.com/cpx075_3.html

Strip of pins, to populate the 1x4. A single strip of
ten, should be enough to account for mistakes. They're cheap
enough, that you can afford to buy extras.

http://www.frontx.com/cpx076.html

The same crimp pins, might fit over the Jaycar terminals.

To get power for such an amplifier, buy a Molex "Y" cable, with
two 1x4 connectors on one end, and one 1x4 on the other end. If
I need Molex connectors for projects, I cut those up to obtain
male or female power connectors, with the wires on one end already
in place. The wire gauge may be too large to crimp comfortably
in the small pins, but you'll be able to work out something there.

To get a signal for the amp, you still need to install a load
resistor across the SPKR terminals, and then your coupling
capacitor goes on "the end that wiggles".

To insulate the wiring when finished (any exposed wire), look
for "Polyolefin" tubing, otherwise known as shrinkwrap. You
apply a little heat, it shrinks, and grabs whatever is underneath.
Once shrunk, the insulation won't slide off on you. I keep about
five different sizes here. Buy the tubing a bit on the big side,
because if you try for a tight fit, the wire gets caught in it.

You should be careful, to insulate the +12V supply lead. If that
shorts to any exposed ground, "sparks will fly". Wrapping
electrical tape around stuff, may sound like a good idea, until
the day it falls off. Shrink wrap is better than electrical tape,
because it uses no heat-sensitive adhesive.

Paul

Paul, Thanks for all the time you've spent on helping me find a solution to
my little problem. Hopefully the little device that PeeCee recommended
might just fit the bill. In regards the links that you have provided in
this message I'm please to say I have all the items already in my spare
parts toolkit. I would also like to express my appreciation to everyone
that has given advice and information, thank you all.