Re: Measurement of pitch


"OG" <owen@xxxxxxxxxxxxxxxxxxx> wrote in message
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<tdp1001@xxxxxxxxx> wrote in message
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OG wrote:
"John Bailey" <john_bailey@xxxxxxxxxxxxxxxx> wrote in message
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On 4 Dec 2006 16:29:27 -0800, matt271829-news@xxxxxxxxxxx wrote:

Hi

At what time in history were the range of frequencies of audible
sounds
first roughly known? Who made the first scientifically accurate
measurement of the frequency of a sound wave, and when?

"Mersenne's description in his Harmonic universelle (1636) of the
first absolute determination of the frequency of an audible tone (at
84 Hz) implies that he already demonstrated that the
absolute-frequency ratio of two vibrating strings, radiating a musical
tone and its octave, is as 1 : 2.

Fascinating

And I found this description of how he did it
"The first major step toward defining pitch into an exact number of
vibrations per second - its frequency - was Mersenne in the 1600s, who
stretched a brass wire 138 feet and counted its vibrations by eye. He
then
stretched smaller wires until they matched the tuning of an organ pipe
and
scaled up the numbers from the long wire and correctly calculated its
frequency."
http://digitalcontentproducer.com/mag/avinstall_measure/

Mersenne's method was not as good
as the method used by the Pythagoreans.

Maybe, but the OP's question was regarding the first scientific
measurement of ACTUAL frequency rather than relative frequency, which was
Pythagoras' work.

Apparently "OG" didn't get the message.

Comparing a frequency directly to a frequency standard
such as middle C, is more precise and more fundamental than
comparing a frequency to an artificial, politically set,
real number, pseudo-frequency such as the second.

As Maxwell pointed out when he formulated Dimensional Analysis,
a measurement consists of two parts,
a reference unit, and a number that represents the number
of these reference units in the quantity to be measured.

The Pythagorians probably used the most stable
instrument available to them, as their reference "atomic clock"
against which to compare all other things that cycled,
vibrated, or could be made to ring,
perhaps including days, months, years, etc.

Hopefully "OG" will explain what "ACTUAL frequency"
really is.

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