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How to measure footstep vibration and noise?

I am on the board of a NYC co-op apartment. Residents of the building
have ongoing issues with excessive noise and vibration resulting from
inadequate floor coverings and unrestrained activity of children in
apartments on the floor above. Some noise in communal living is
expected. However, there are situations which seem out of control.
What, if any, equipment is available that could provide an effective
measure of this type of impact/vibration noise so that our residents
are not forced into situations where one person's word is pitted
against another's?

I know very little about electronics so simple explanations would be
extremely helpful. Would a seismometer be useful? Something using an
accelerometer? It doesn't seem like an ordinary noise meter would
register the problem when the jarring vibrations of the impact are
frequently more the issue than the actual noise. And just how
prohibitively expensive would such equipment be?

Thank you.
 
L

Leon

Jan 1, 1970
0
I am on the board of a NYC co-op apartment.  Residents of the building
have ongoing issues with excessive noise and vibration resulting from
inadequate floor coverings and unrestrained activity of children in
apartments on the floor above.  Some noise in communal living is
expected.  However, there are situations which seem out of control.
What, if any, equipment is available that could provide an effective
measure of this type of impact/vibration noise so that our residents
are not forced into situations where one person's word is pitted
against another's?

I know very little about electronics so simple explanations would be
extremely helpful.  Would a seismometer be useful?  Something using an
accelerometer?  It doesn't seem like an ordinary noise meter would
register the problem when the jarring vibrations of the impact are
frequently more the issue than the actual noise.  And just how
prohibitively expensive would such equipment be?

Thank you.

Whilst an accelerometer or a geophone could be used to measure impacts
and vibration, you would have a problem calibrating it so that you got
data which actually meant something and could be used for enforcement
purposes.

I once interfaced a geophone to an AVR and transmitted the data to a
PC via RS-232. The total cost was about $100, IIRC. I still have the
hardware somewhere.

Leon
 
Yes, calibration would be an issue, I'm sure. And a refusal to change
behavior, as Tim says, won't necessarily be helped by technology. We
are currently just trying to see if there is any way to measure at
all. The hope would be that it might give the Board some slight
leverage for mediating these situations if the offenders can be shown
that the complainants are not just overly-sensitive troublemakers but
have a legitimate, measurable grievance -- or, conversely, if the
complainants can be shown that the vibration is no greater than that
in any other apartment.

I'll do some research on geophones. It's hard to find sites that are
geared to the non-expert.

Your responses are much appreciated.
 
P

Phil Allison

Jan 1, 1970
0
I am on the board of a NYC co-op apartment. Residents of the building
have ongoing issues with excessive noise and vibration resulting from
inadequate floor coverings and unrestrained activity of children in
apartments on the floor above. Some noise in communal living is
expected. However, there are situations which seem out of control.
What, if any, equipment is available that could provide an effective
measure of this type of impact/vibration noise so that our residents
are not forced into situations where one person's word is pitted
against another's?


** Have you even tried and SPL meter yet ???

The sort of noises you allude to ARE mostly in the audible range - ie
footsteps on smooth surface floors will be heard in the apartment below by
direct transmission and impacts on the same floor will shake the entire
floor at some low but audible frequency.

Any decent SPL meter allows testing with a flat response or " C curve "
weighting, both of which will show low frequency noises very clearly.

IME - the use of carpets with foam underlay is essential in apartment
blocks, on all living area floors except the very lowest level one.


...... Phil
 
Yes, calibration would be an issue, I'm sure.  And a refusal to change
behavior, as Tim says, won't necessarily be helped by technology.  We
are currently just trying to see if there is any way to measure at
all.  The hope would be that it might give the Board some slight
leverage for mediating these situations if the offenders can be shown
that the complainants are not just overly-sensitive troublemakers but
have a legitimate, measurable grievance -- or, conversely, if the
complainants can be shown that the vibration is no greater than that
in any other apartment.

I'll do some research on geophones.  It's hard to find sites that are
geared to the non-expert.

Your responses are much appreciated.

I'm not sure a geophone is the way to go these days. I bought an
accelerometer from Sparkfun and geek that I am, found it fascinating.
http://www.sparkfun.com/commerce/categories.php?c=23
The signal conditioning is right on the chip. I had mine connected to
a scope, but it seems to me you could drive a soundcard.

Of course, I'd probably find a geophone fun too. You can get them in
old seismic detectors used by the military. Murphy has them, though
you can always get Murphy's stuff at a third the price if you poke
around:
http://www.murphyjunk.bizland.com/id11.html
 
L

Leon

Jan 1, 1970
0
I'm not sure a geophone is the way to go these days. I bought an
accelerometer from Sparkfun and geek that I am, found it fascinating.http://www.sparkfun.com/commerce/categories.php?c=23
The signal conditioning is right on the chip. I had mine connected to
a scope, but it seems to me you could drive a soundcard.

Of course, I'd probably find a geophone fun too. You can get them in
old seismic detectors used by the military. Murphy has them, though
you can always get Murphy's stuff at a third the price if you poke
around:http://www.murphyjunk.bizland.com/id11.html

An accelerometer PCB would be difficult to couple efficiently to the
building structure without a lot of extra work. Geophones usually have
a shaft that can easily be attached to the floor.

Leon
 

neon

Oct 21, 2006
1,325
Joined
Oct 21, 2006
Messages
1,325
GET AN AUDIO AMPLIFIER with a sensitive microphone then when the audio reaches a certain level blast a horn and sustain until the noise subsides. then everybody will have a choise quite down or hear the horn or sonalert of 95 Db that will get everybody attention. Another choice is move. That you can buy or make easy $25
 
An accelerometer PCB would be difficult to couple efficiently to the
building structure without a lot of extra work. Geophones usually have
a shaft that can easily be attached to the floor.

Leon

Actually the geophones have a spike to hammer into the ground.

The sparkfun accelerometers are on PC boards. You could mount the
board to a plate using spacers, then mount the plate to the floor.

The deal with the geophone is you probably need signal conditioning. I
see them being like a moil coil phono cartridge, so you might be able
to steal circuits for that application, but it's all very low level
stuff. There is a LT1028 design for moving coil preamp design, though
you need to remove the RIAA equalization circuit.

Amazing, there are no geophones for sale on ebay. It must be a slow
week. I found a few on the net here:
http://psn.quake.net/geophone/index.html

http://www.vaxman.de/projects/geophon_amplifier/geophon_amplifier.html
I think you can do better than that design. The LT1028 and a few
others are very quite op amps.
http://www.linear.com/pc/productDetail.jsp?navId=H0,C1,C1154,C1009,C1021,P1234
 
Wow! So much help! I'll need to do some more reading and research,
because I don't think I understand everything you've said, but I'm
very grateful for for all the suggestions and the links.

Thank you!
 
R

Robert Monsen

Jan 1, 1970
0
I am on the board of a NYC co-op apartment. Residents of the building
have ongoing issues with excessive noise and vibration resulting from
inadequate floor coverings and unrestrained activity of children in
apartments on the floor above. Some noise in communal living is
expected. However, there are situations which seem out of control.
What, if any, equipment is available that could provide an effective
measure of this type of impact/vibration noise so that our residents
are not forced into situations where one person's word is pitted
against another's?

I know very little about electronics so simple explanations would be
extremely helpful. Would a seismometer be useful? Something using an
accelerometer? It doesn't seem like an ordinary noise meter would
register the problem when the jarring vibrations of the impact are
frequently more the issue than the actual noise. And just how
prohibitively expensive would such equipment be?

Thank you.

You can buy a sound level meter from radio shack that has a 'record
maximum' feature. Duct tape it someplace safe, and see what it comes
up with.

You could also use a PC for this. There are audio analysis programs
available on the web that will record. If you have a safe place to put
it, that is probably the easiest way to go. Audigy is a freeware sound
client that would work for this.

Regards,
Bob Monsen
 
P

Phil Allison

Jan 1, 1970
0
"Robert Monsen"

You can buy a sound level meter from radio shack that has a 'record
maximum' feature. Duct tape it someplace safe, and see what it comes
up with.


** The fuckwit OP has posted his same message on other NGs - and got the
same answer re the use of an ordinary SPL meter to quantify the problem.

He has so far studiously IGNORED all of them.

Also, the OP has provided no information of the nature of these suspended
floor - are they concrete slabs?

What size / area are they?

Perhaps they are unusually big for a residential premises.



...... Phil
 
You can buy a sound level meter from radio shack that has a 'record
maximum' feature. Duct tape it someplace safe, and see what it comes
up with.

You could also use a PC for this. There are audio analysis programs
available on the web that will record. If you have a safe place to put
it, that is probably the easiest way to go. Audigy is a freeware sound
client that would work for this.

Regards,
 Bob Monsen

I think you means Audacity
http://audacity.sourceforge.net/
It seems you can set the sample rate as low as 1Hz. Probably 1kHz
would make sense for this application.
 
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