Hey, I’ve got some bootleg recordings that I know are for sure a tiny bit off pitch. However, I haven’t found a way to determine how much out of tune the recordings are. Finding the frequencies doesn’t seem to help, as Audacity seems to only give the note most closest to the off pitch note. Was I confusing enough?
Please someone help, this is semi-urgent. Thank you
Are you using Analyze > Plot Spectrum ?
Yes. It shows multiple different frequencies for the same notes, on both “cursor” and “peak”, so I guess it’s never perfectly accurate, or accurate enough.
Yes, so here is the Analyze Spectrum for a recording of a real G-string on a guitar:
The lowest (and loudest) peak is at G3=194 Hz. The other peaks are harmonics and are typically smaller and are typically found at octave intervals (194Hz x2, x3, x4, x5, etc.) In this particular case, the G4 peak happens to be at 395 which is 197.5x2. Note with 440 tuning, G3 should be at 196Hz.
Note that the real world does not always conform to our expectations. 
There’s a plug-in here that is pretty good at detecting the pitch of single notes: Nyquist Analyze Plug-ins - Audacity Wiki
It doesn’t work with chords / multiple notes playing at the same time.
If it’s not too far off, any dominant-sustained frequency that you can see in the spectrum display should work.
Find the actual frequency, then find the closest frequency that represents a note. Calculate percentage difference and use the Change Speed effect to change the pitch & frequency together. (Any accidental pitch shift will be accompanied by a corresponding speed-tempo change.)
Note that some soundcards are “imperfect”… The sample rate clock (44.1kHz, etc.) can be off and that will affect the speed and pitch. And of course, that affects everything played on that soundcard. (The soundcard isn’t used in the spectrum analysis but it will affect what you hear.)
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