The Analyzer Settings are the most important settings in Overtone Analyzer because they determine the frequency and time resolution and other aspects of the spectrum and spectrogram. Understanding them requires a little bit of background knowledge about digital audio and the Fast Fourier Transform (FFT), which will be explained later in this manual.
Sampling Rate
Sampling Rate determines the number of measurements (samples) per second recorded from the input source. You can measure frequencies of up to half the sampling rate. For example, if the sampling rate is 11025 samples per second, then the analyzer can measure frequencies up to around 5500Hz. Standard music CDs have a sampling rate of 44100Hz. This should be a reasonable setting for most practical purposes, as it gives a good balance between frequency resolution and sound quality (however, see the discussion below).
Note: This option is only available if you have not loaded any file or made any recording. The sampling rate of existing recordings cannot be changed. If you want to change the sampling rate and it is disabled, click on File / New first.
Frequency Resolution (FFT Size)
The frequency resolution is the smallest difference between two frequencies that the analyzer can distinguish. Internally, this setting is stored as the size of the Fast Fourier Transform, which is the number of points that are computed for each update.
A higher FFT Size gives you more accuracy and shows more detail in the spectrum and spectrogram, but it also requires more processing power and may slow down your computer. In general, you should choose the highest setting that still gives you acceptable performance when moving the range slider on the timeline.
Time Resolution (updates per second)
This is the most important setting in determining what you want to measure.
Displayed Time Range
Window Function
