Reply by glen herrmannsfeldt●September 4, 20072007-09-04
SoundOff wrote:
> I�m investigating an irritating sound in the building I live in. The sound
> disappears at 22.58 a clock. I have traced the sound to about 144 Hz with a
> program called Spectran. There I can se that it disappears at 22.57 a clock.
> The janitor says it may be a water circulation pump in the seller that makes
> the sound.
That is common in large, or even not so large buildings. It keeps the
hot water close to the people that need it, usually located near
the hot water heater. The sound follows the pipes, so you can probably
hear it a long ways away, at least at night when other sounds go away.
-- glen
Reply by Clay●September 4, 20072007-09-04
On Sep 4, 3:08 pm, "SoundOff" <so...@google.net> wrote:
> Hello
>
> I'm investigating an irritating sound in the building I live in. The sound
> disappears at 22.58 a clock. I have traced the sound to about 144 Hz with a
> program called Spectran. There I can se that it disappears at 22.57 a clock.
>
> The janitor says it may be a water circulation pump in the seller that makes
> the sound.
>
> I would want another program that allows filtering the sound round 144Hz and
> presenting the sound level with a VU-meter, are there any such programs
> around?
>
> I also have access to MATLAB, is it possible to do this in Simulink (real
> time sound input)?
Invite a buddy (one who has a cellphone) over to your place and send
him down to the basement to the circuit breaker panel. You phone him
when you hear the sound. He will start turning off the breakers one at
a time. When the noise goes away, you'll know which circuit the
offending sound source is on. Leave the breaker turned off until
someone complains about whatever is on it not working anymore. Now you
will have narrowed your search down quite a bit.
I think this approach is a bit more effacacious than building a
detector for the sound.
IHTH,
Clay
Reply by ●September 4, 20072007-09-04
On Sep 5, 7:08 am, "SoundOff" <so...@google.net> wrote:
> Hello
>
> I'm investigating an irritating sound in the building I live in. The sound
> disappears at 22.58 a clock. I have traced the sound to about 144 Hz with a
> program called Spectran. There I can se that it disappears at 22.57 a clock.
>
> The janitor says it may be a water circulation pump in the seller that makes
> the sound.
>
> I would want another program that allows filtering the sound round 144Hz and
> presenting the sound level with a VU-meter, are there any such programs
> around?
>
> I also have access to MATLAB, is it possible to do this in Simulink (real
> time sound input)?
> Click settings, Extended GUI
> Click the Equalizer tab, "enable" on
> Turn on 2-pass (gives sharper filters), BUT back off the preamp gain to
-10 dB or so
> Experiment with the settings, what gives the desired result.
DSP in a wider sense...
Cheers
Markus
Reply by SoundOff●September 4, 20072007-09-04
Hello
I�m investigating an irritating sound in the building I live in. The sound
disappears at 22.58 a clock. I have traced the sound to about 144 Hz with a
program called Spectran. There I can se that it disappears at 22.57 a clock.
The janitor says it may be a water circulation pump in the seller that makes
the sound.
I would want another program that allows filtering the sound round 144Hz and
presenting the sound level with a VU-meter, are there any such programs
around?
I also have access to MATLAB, is it possible to do this in Simulink (real
time sound input)?