Re: HUM_FORUM: Earthshaking technology

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It isn't a 60 cycle hum?

While i have never heard geophysical vibrations, i believe i have felt them since i was a kid. I have played around a bit with the Schuman resonance and have noticed a difference not when using it, but the absence of something when i move away.

mikal haley wrote:
>
> i once performed in a rock band with a guitarist with a very sensitive > ear.
> he claimed that "line hum", the hum that comes out when an electric > instrument is plugged into an amplifier and turned to high volume > without any notes being struck - had a different note-value in > different parts of the united states. i would like to test that theory > if possible.
>
> On Sat, Mar 8, 2008 at 6:22 AM, coer_12 <coer_12@yahoo.com > <mailto:coer_12@yahoo.com>> wrote:
>
> The usual disclaimer: this isn't the answer for the universal hum.
>
> Given the possibility that a percentage of hearers might also be
> sensitive to geophysical vibration this might be something to consider
> if you live in a rural area, or area known for such exploration.
>
> http://en.wikipedia.org/wiki/Reflection_seismology
> <http://en.wikipedia.org/wiki/Reflection_seismology>
>
> Follow some of the key words for more information about use and study
> areas.
>
>
>
>
> -- > very new!
>
> http://particlezen.proboards7.com/index.cgi > <http://particlezen.proboards7.com/index.cgi>?
>
> the*edge*of*everything*
>
>
>
>
> the jailers cannot cultivate such ways of seeing and remain jailers.
> -- Kraig Grady
North American Embassy of Anaphoria Island <http://anaphoria.com/index.html>
The Wandering Medicine Show
KXLU <http://www.kxlu.com/main/index.asp> 88.9 FM Wed 8-9 pm Los Angeles

mikal haley wrote:
> > > i once performed in a rock band with a guitarist with a very sensitive ear.
> he claimed that "line hum", the hum that comes out when an electric > instrument is plugged into an amplifier and turned to high volume > without any notes being struck - had a different note-value in different > parts of the united states. i would like to test that theory if possible.

While the line *voltage* is subject to variations based on localities, etc., the line *frequency* (60 HZ standard in the USA) is very well regulated and typically would vary less than 1 percent. Anyone who claims to be able to hear such variations is probably either delusional or believes his pitch discrimination is much better than it actually is.

Cheap electric clocks gain or lose very little time as long as the power supply is continuous. If there was audible variation in the line frequency, they would drift more than they do.

If you want to "test that theory", what I would recommend doing is sending an email to the head of the electrical engineering department at every major land-grant university in the USA, telling him or her what you want to do. My guess is that the typical response will be that you are wasting your time and the time of the EE department, but you might find a few that are willing to go along with it and will find an undergrad willing to help you understand where you are wrong. :)

From http://en.wikipedia.org/wiki/Utility_frequency:

"Stability

"The frequency of large interconnected power distribution systems is tightly regulated so that, over the course of a day, the average frequency is maintained at the nominal value within a few hundred parts per million.[13] While this allows simple electric clocks and motors, based on synchronous electric motors, to keep accurate time, the primary reason for accurate frequency control is to allow the flow of alternating current power from multiple generators through the network to be controlled. The trend in system frequency is a measure of mismatch between demand and generation, and so is a necessary parameter for load control in interconnected systems. Regulation of power system frequency for timekeeping accuracy was not commonplace until after 1926 and the invention of the electric clock driven by a synchronous motor.

"Frequency of the system will vary as load and generation change. Increasing the mechanical input power to a synchronous generator will not greatly affect the system frequency but will produce more electric power from that unit. During a severe overload caused by tripping or failure of generators or transmission lines the power system frequency will decline, due to an imbalance of load versus generation. Loss of an interconnection, while exporting power (relative to system total generation) will cause system frequency to rise. AGC (automatic generation control) is used to maintain scheduled frequency and interchange power flows.

"Frequency protection relays on the power system network sense the decline of frequency and automatically initiate load shedding or tripping of interconnection lines, to preserve the operation of at least part of the network. Small frequency deviations (i.e.- 0.5 Hz on a 50 Hz or 60 Hz network) will result in automatic load shedding or other control actions to restore system frequency.

"Smaller power systems, not extensively interconnected with many generators and loads, will not maintain frequency with the same degree of accuracy. Where system frequency is not tightly regulated during heavy load periods, the system operators may allow system frequency to rise during periods of light load, to maintain a daily average frequency of acceptable accuracy."

Perhaps voltage variations have enough effect on the tone of the
guitarist's amp that he's hearing timbre variations? That might
account for a feeling that the pitch is different.

--- In tuning@yahoogroups.com, "M. Edward (Ed) Borasky" <znmeb@...>
wrote:
>
> mikal haley wrote:
> >
> >
> > i once performed in a rock band with a guitarist with a very
sensitive ear.
> > he claimed that "line hum", the hum that comes out when an
electric
> > instrument is plugged into an amplifier and turned to high volume
> > without any notes being struck - had a different note-value in
different
> > parts of the united states. i would like to test that theory if
possible.
>
> While the line *voltage* is subject to variations based on
localities,
> etc., the line *frequency* (60 HZ standard in the USA) is very well
> regulated and typically would vary less than 1 percent. Anyone who
> claims to be able to hear such variations is probably either
delusional
> or believes his pitch discrimination is much better than it
actually is.
>
> Cheap electric clocks gain or lose very little time as long as the
power
> supply is continuous. If there was audible variation in the line
> frequency, they would drift more than they do.
>
> If you want to "test that theory", what I would recommend doing is
> sending an email to the head of the electrical engineering
department at
> every major land-grant university in the USA, telling him or her
what
> you want to do. My guess is that the typical response will be that
you
> are wasting your time and the time of the EE department, but you
might
> find a few that are willing to go along with it and will find an
> undergrad willing to help you understand where you are wrong. :)
>
> From http://en.wikipedia.org/wiki/Utility_frequency:
>
> "Stability
>
> "The frequency of large interconnected power distribution systems
is
> tightly regulated so that, over the course of a day, the average
> frequency is maintained at the nominal value within a few hundred
parts
> per million.[13] While this allows simple electric clocks and
motors,
> based on synchronous electric motors, to keep accurate time, the
primary
> reason for accurate frequency control is to allow the flow of
> alternating current power from multiple generators through the
network
> to be controlled. The trend in system frequency is a measure of
mismatch
> between demand and generation, and so is a necessary parameter for
load
> control in interconnected systems. Regulation of power system
frequency
> for timekeeping accuracy was not commonplace until after 1926 and
the
> invention of the electric clock driven by a synchronous motor.
>
> "Frequency of the system will vary as load and generation change.
> Increasing the mechanical input power to a synchronous generator
will
> not greatly affect the system frequency but will produce more
electric
> power from that unit. During a severe overload caused by tripping
or
> failure of generators or transmission lines the power system
frequency
> will decline, due to an imbalance of load versus generation. Loss
of an
> interconnection, while exporting power (relative to system total
> generation) will cause system frequency to rise. AGC (automatic
> generation control) is used to maintain scheduled frequency and
> interchange power flows.
>
> "Frequency protection relays on the power system network sense the
> decline of frequency and automatically initiate load shedding or
> tripping of interconnection lines, to preserve the operation of at
least
> part of the network. Small frequency deviations (i.e.- 0.5 Hz on a
50 Hz
> or 60 Hz network) will result in automatic load shedding or other
> control actions to restore system frequency.
>
> "Smaller power systems, not extensively interconnected with many
> generators and loads, will not maintain frequency with the same
degree
> of accuracy. Where system frequency is not tightly regulated during
> heavy load periods, the system operators may allow system frequency
to
> rise during periods of light load, to maintain a daily average
frequency
> of acceptable accuracy."
>