using pitch change app to measure frequency

[Stuart Gelzer]

(Using Audacity 1.3.13-beta on Windows 7.)

I'm trying to use the pitch change app in Effects just to measure the frequency of pitches. Problem is, I get wildly different results (up to 60 cents off) depending on whether I highlight the whole of a held note or only part of it, or only the first half, or only the second half, etc. In fact, almost every 1/10 second slice of the note gives me different results. This is true whether the input is voice, bassoon, or even piano. I'm only measuring solo notes, so there's no issue of confusing background pitches.

Anybody have an idea what I'm doing wrong, or if there's a better way to do what I'm trying to do? Thanks.

[steve]

You will probably get more accurate results using "Analyze > Plot Spectrum" http://manual.audacityteam.org/man/Anal ... u#spectrum
Set the "Size" to a high value for greater frequency precision (maximum is 16384).
You will probably want the "Axis" set to "Log Frequency".
The other settings will probably be best at their defaults.

[Stuart Gelzer]

Thank you -- I'm getting interesting results. Is there any way to have the spectrum plotter give results down to the tenth of a Herz? (In what I'm analyzing, rounding to the nearest whole Hertz produces a margin of error of about 8 cents, which is a large ambiguity for the microtuned scales I'm studying.) As you recommended, I'm already at the highest size setting.

[steve]

Is there any way to have the spectrum plotter give results down to the tenth of a Herz?

Not with Audacity. You need something a bit more specialised, such as Sonic Visualizer

[steve]

Sonic Visualizer showing the frequency of a 440.4 Hz sine tone:

Sonic Visualiser_440-5_Hz.png (92.59 KiB) Viewed 775 times

[Stuart Gelzer]

Wow, Sonic Visualiser is like a fire hose of data: just what I was looking for -- unless it drowns me in information. Thank you again.