centz to hertz

Anyone know of (or could program) a simple cents to Hertz (and vice
versa) converter. Including just ratios and equal temperaments would
help also. Thanks...

/Ö
I'm gonna try out the Oasys now...

--- oljare <oljare@hotmail.com> wrote:
>
> Anyone know of (or could program) a simple cents to
> Hertz (and vice
> versa) converter. Including just ratios and equal
> temperaments would
> help also. Thanks...
>
> /�
> I'm gonna try out the Oasys now...
>
***********************************************
Suppose $f_1$ and $f_2$ are two pitches, measured in
Hertz, and $c_1$ and $c_2$ their respective
deviations, measured in cents, from a common reference
pitch R.

The algebraic relations between these measures are
given by f_1=R*2^(c_1/1200) and f_2=R*2^(c_2/1200).

Taking natural logarithms,
LN(f_1)=LN(R)+(c_1/1200)*LN(2) and
LN(f_2)=LN(R)+(c_2/1200)*LN(2), and subtracting these
two equalities we get
LN(f_1)-LN(f_2)=(LN(2)/1200)*(c_1-c_2), from which
follows the expression
c_1-c_2=1200*[LN(f_1)-LN(f_2)]/LN(2) for the
deviation, measured in cents, between the two pitches
f_1 and f_2.

Similarly one can go in the other direction...

I hope this helps.

=====
Can Akkoc
1058 Dickenson Avenue
Mobile, AL 36609
USA
(251)639-1936

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--- In tuning@y..., "oljare" <oljare@h...> wrote:
>
> Anyone know of (or could program) a simple cents to Hertz (and vice
> versa) converter.

hertz measures frequency and cents measures interval.

if f1 and f2 are two frequencies, the interval between them is

log(f1/f2)/log(2) * 1200 cents;

if f1 is a base frequency in Hz, the frequency c cents above is

f1 * 2^(c/1200) Hz.

> Including just ratios and equal temperaments would
> help also.

i'm not sure what you mean . . . can you clarify?

--- In tuning@y..., "emotionaljourney22" <paul@s...> wrote:

/tuning/topicId_37043.html#37057

> --- In tuning@y..., "oljare" <oljare@h...> wrote:
> >
> > Anyone know of (or could program) a simple cents to Hertz (and
vice
> > versa) converter.
>
> hertz measures frequency and cents measures interval.
>
> if f1 and f2 are two frequencies, the interval between them is
>
> log(f1/f2)/log(2) * 1200 cents;
>
> if f1 is a base frequency in Hz, the frequency c cents above is
>
> f1 * 2^(c/1200) Hz.
>

***Thanks, Paul, for simplifying things with these convenient
formulas which I had someplace, but misplaced or such like.

Joseph