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atomottokar
June 9th 13, 09:09 AM
hello

what is the difference betwenn cents and Hrz ?
is there an equivalence ?

thanks

John Williamson
June 9th 13, 01:21 PM
atomottokar wrote:
> hello
>
> what is the difference betwenn cents and Hrz ?
> is there an equivalence ?
>
Hz is the frequency of a note. For example, middle A in normal usage,
also known as concert pitch, is 440Hz. The A below that is 220Hz, and
the one above it is 880Hz.

Cents is a way of telling the difference between two notes where an
octave difference is 1200 cents. The actual difference in frequency when
two notes are, say 10 cents apart varies with the notes, but it is
always the same ratio, so, because of the way our ears work, the
difference always sounds more or less the same. the difference in Hz can
be worked out if you know the difference between a pair of notes in
cents, and what one of the notes is.

http://en.wikipedia.org/wiki/Cent_%28music%29

For a painful listening experience, try an accordion band where each
instrument differs by a few cents from its companions.<Shudders>
Amazingly, the CD still sold....

Tciao for Now!

John.

geoff
June 9th 13, 01:35 PM
"atomottokar" > wrote in message
...
>
> hello
>
> what is the difference betwenn cents and Hrz ?

One is a proportion betweentwo notes, the other is an absolute frequency.

> is there an equivalence ?

No - not a linear one at least. Different Hertz for each different note and
cent.

geoff

Reinhard Zwirner[_2_]
June 9th 13, 03:05 PM
John Williamson schrieb:
> atomottokar wrote:
>> hello
>> what is the difference betwenn cents and Hrz ? is there an
>> equivalence ?
>>
> Hz is the frequency of a note. For example, middle A in normal usage,
> also known as concert pitch, is 440Hz. The A below that is 220Hz, and
> the one above it is 880Hz.
>
> Cents is a way of telling the difference between two notes where an
> octave difference is 1200 cents. [...]

Therefore:

a = 220 Hz a1 = 440 Hz a2 = 880 Hz

difference [Hz] 220 440
difference [cents] 1200 1200

Within an octave there are 12 semitone steps; each semitone step
equals 100 cents.

HTH

Reinhard

Peter A. Stoll[_2_]
June 9th 13, 03:32 PM
atomottokar > wrote:

>what is the difference betwenn cents and Hrz ?
>is there an equivalence ?
One is an absolute measurement--the other is a ratio. A single cent is a ratio of the
twelve hundredth root of two. Given how tiny a difference of a few cents is, it is a bit
surprising how bad even eight cents worth of non-unison tuning can make a single
note on a piano sound.

Les Cargill[_4_]
June 9th 13, 04:23 PM
atomottokar wrote:
>
> hello
>
> what is the difference betwenn cents and Hrz ?
> is there an equivalence ?
>
> thanks
>
>
>
>

One cent is 1/100th of a half step/semitone.

The ratio in frequency for one half step is
1.0594630943592952645618252949463 ( the twelfth root of 2 )

So one cent would be 0.01059463094359295264561825294946 Hz

--
Les Cargill

Les Cargill[_4_]
June 9th 13, 04:33 PM
geoff wrote:
>
> "atomottokar" > wrote in message
> ...
>>
>> hello
>>
>> what is the difference betwenn cents and Hrz ?
>
> One is a proportion betweentwo notes, the other is an absolute frequency.
>
>> is there an equivalence ?
>
> No - not a linear one at least. Different Hertz for each different note and
> cent.
>
> geoff
>
>


It is a fixed ratio of frequency.

Give two frequencies F1 and F2 such
than F1 is the larger of the two,

cents = (F1/F2) * (exp(2,-12)/100)

where exp(2,-12) means "the twelfth root of 2" and
is a *real* expression of the number of semitones between
the two frequencies.

--
Les Cargill

Les Cargill[_4_]
June 9th 13, 04:35 PM
Peter A. Stoll wrote:
>
> atomottokar > wrote:
>
>> what is the difference betwenn cents and Hrz ?
>> is there an equivalence ?
> One is an absolute measurement--the other is a ratio. A single cent is a ratio of the
> twelve hundredth root of two.

That's 1/100th of the twelfth root of 2 - I am fairly sure those are
not the same thing. :)

> Given how tiny a difference of a few cents is, it is a bit
> surprising how bad even eight cents worth of non-unison tuning can make a single
> note on a piano sound.
>

--
Les Cargill

Don Pearce[_3_]
June 9th 13, 04:51 PM
On Sun, 09 Jun 2013 10:23:45 -0500, Les Cargill
> wrote:

>atomottokar wrote:
>>
>> hello
>>
>> what is the difference betwenn cents and Hrz ?
>> is there an equivalence ?
>>
>> thanks
>>
>>
>>
>>
>
>One cent is 1/100th of a half step/semitone.
>
>The ratio in frequency for one half step is
>1.0594630943592952645618252949463 ( the twelfth root of 2 )
>
>So one cent would be 0.01059463094359295264561825294946 Hz

No, this isn't right, even in its own terms. You have to knock off the
1 before you do the division, then add it back on again afterwards.

But it is factually wrong too. . Just taking 100th of the semitone
would stitch the pitches together with a set of straight lines. The
cent maintains the logarithmic ratio and blends the notes properly
into each other with a curve.

1 cent is the 1200th root of 2., or 1.00057778951.

d

Les Cargill[_4_]
June 9th 13, 05:38 PM
Don Pearce wrote:
> On Sun, 09 Jun 2013 10:23:45 -0500, Les Cargill
> > wrote:
>
>> atomottokar wrote:
>>>
>>> hello
>>>
>>> what is the difference betwenn cents and Hrz ?
>>> is there an equivalence ?
>>>
>>> thanks
>>>
>>>
>>>
>>>
>>
>> One cent is 1/100th of a half step/semitone.
>>
>> The ratio in frequency for one half step is
>> 1.0594630943592952645618252949463 ( the twelfth root of 2 )
>>
>> So one cent would be 0.01059463094359295264561825294946 Hz
>
> No, this isn't right, even in its own terms. You have to knock off the
> 1 before you do the division, then add it back on again afterwards.
>
> But it is factually wrong too. . Just taking 100th of the semitone
> would stitch the pitches together with a set of straight lines. The
> cent maintains the logarithmic ratio and blends the notes properly
> into each other with a curve.
>
> 1 cent is the 1200th root of 2., or 1.00057778951.
>
> d
>


Yep - you are absolutely right - my bad.

--
Les Cargill

Les Cargill[_4_]
June 9th 13, 05:43 PM
Les Cargill wrote:
> Peter A. Stoll wrote:
>>
>> atomottokar > wrote:
>>
>>> what is the difference betwenn cents and Hrz ?
>>> is there an equivalence ?
>> One is an absolute measurement--the other is a ratio. A single cent
>> is a ratio of the
>> twelve hundredth root of two.
>
> That's 1/100th of the twelfth root of 2 - I am fairly sure those are
> not the same thing. :)
>

Don Pearce graciously corrected me on this - one cent is the 1200th root
of 2, not 1/100th of the 12 root of 2.

>> Given how tiny a difference of a few cents is, it is a bit
>> surprising how bad even eight cents worth of non-unison tuning can
>> make a single
>> note on a piano sound.
>>
>
> --
> Les Cargill

--
Les Cargill

None
June 9th 13, 06:09 PM
"Les Cargill" > wrote in message
...
>> One is an absolute measurement--the other is a ratio. A single
>> cent is a ratio of the
>> twelve hundredth root of two.
>
> That's 1/100th of the twelfth root of 2 - I am fairly sure those
> are not the same thing. :)

No, a cent is the 1200th root of 2. It is not 1/100 of the 12th root
of 2.

None
June 9th 13, 06:17 PM
"Les Cargill" > wrote in message
...
> cents = (F1/F2) * (exp(2,-12)/100)

The expression above is not correct; it has multiple problems.

The correct formula is this:
cents = 1200 * log2(F2/F1)

geoff
June 9th 13, 10:43 PM
"Les Cargill" > wrote in message
...
> atomottokar wrote:
>>
>> hello
>>
>> what is the difference betwenn cents and Hrz ?
>> is there an equivalence ?
>>
>> thanks
>>
>>
>>
>>
>
> One cent is 1/100th of a half step/semitone.

One cent is 1/100th of a dollar.

geoff

Trevor
June 10th 13, 08:46 AM
"geoff" > wrote in message
...
> "Les Cargill" > wrote in message
> ...
>> atomottokar wrote:
>>>
>>> hello
>>>
>>> what is the difference betwenn cents and Hrz ?
>>> is there an equivalence ?
>>>
>>> thanks
>>
>> One cent is 1/100th of a half step/semitone.
>
> One cent is 1/100th of a dollar.


Centi is simply the metric prefix for 1/100 (or 10^-2) of any unit. In this
case a semi-tone instead of a dollar.

Trevor.

None
June 10th 13, 12:24 PM
"Trevor" > wrote in message
...
>> One cent is 1/100th of a dollar.
>
>
> Centi is simply the metric prefix for 1/100 (or 10^-2) of any unit.
> In this case a semi-tone instead of a dollar.

In these cases (1/100 of a semitone and 1/100 of dollar), there is no
metric unit, and no metric prefix.

Luxey
June 10th 13, 12:56 PM
On Sunday, 9 June 2013 19:09:09 UTC+2, None wrote:
> "Les Cargill" > wrote in message
>
> ...
>
> >> One is an absolute measurement--the other is a ratio. A single
>
> >> cent is a ratio of the
>
> >> twelve hundredth root of two.
>
> >
>
> > That's 1/100th of the twelfth root of 2 - I am fairly sure those
>
> > are not the same thing. :)
>
>
>
> No, a cent is the 1200th root of 2. It is not 1/100 of the 12th root
>
> of 2.

Yes, and that makes it even more useless. Regardless of formula, cents are relative, you have to arbitrary choose the reference point.
Now play me 1309 cents note? Not possible. Or too much possible?

John Williamson
June 10th 13, 01:46 PM
Luxey wrote:
> On Sunday, 9 June 2013 19:09:09 UTC+2, None wrote:
>> No, a cent is the 1200th root of 2. It is not 1/100 of the 12th root
>>
>> of 2.
>
> Yes, and that makes it even more useless. Regardless of formula, cents are relative, you have to arbitrary choose the reference point.
> Now play me 1309 cents note? Not possible. Or too much possible?

I can play you a note 1309 cents above or below the one you play for
me... The thing about using cents is that it doesn't matter which octave
or note you start with, a note that is 100 cents higher is *always* a
semitone up, and a note 50 cents higher is *always* half a semitone up.

Knowing how many cents out of tune an instrument is can be of great use
when editing a recording or if you're retuning an instrument to play a
different scale, then knowing that a particular note on scale 1 is a
certain number of cents different from the nearest note on scale 2 is
also very handy.

--
Tciao for Now!

John.

None
June 11th 13, 01:58 AM
"Luxey" > wrote in message
...
> On Sunday, 9 June 2013 19:09:09 UTC+2, None wrote:
>> No, a cent is the 1200th root of 2. It is not 1/100 of the 12th
>> root
>>
>> of 2.
>
> Yes, and that makes it even more useless.

> Regardless of formula, cents are relative, you have to arbitrary
> choose the reference point.

Very much like decibels, which like cents, are not useless at all.

> Now play me 1309 cents note? Not possible.

No, not possible. Any more than it would be possible to play a 1309
semitone note.
That's not what cents are useful for. And it doesn't make semitone
useless. Cents, like semitones, are used to measure, describe, and
specify musical intervals. Very useful indeed in the contexts in which
they are used.

> Or too much possible?

June 11th 13, 10:43 PM
Here's a conversion calculator-
http://www.sengpielaudio.com/calculator-centsratio.htm

Trevor
June 13th 13, 06:26 AM
"None" > wrote in message
m...
>>> One cent is 1/100th of a dollar.
>>
>> Centi is simply the metric prefix for 1/100 (or 10^-2) of any unit. In
>> this case a semi-tone instead of a dollar.
>
> In these cases (1/100 of a semitone and 1/100 of dollar), there is no
> metric unit, and no metric prefix.

Where the hell do you think the term "cent" came from in the first place? I
did NOT say it was a *prefix* in this case.

Trevor.