User Manual

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Analysis
Creating the graph
1. Select the part of the file you want to analyse.
If you select a stereo recording, a mix of the two channels will be analy-
sed.
2. Select “3D Frequency analysis options” from the Anal-
ysis menu and click on the Frequency tab. Adjust the set-
tings if needed.
These are the only settings that cannot be redone when the graph is al-
ready open.
3. If you only want to see a plot for a part of the frequency
range, adjust the “From” and “To” values.
The range must always span at least three octaves.
4. Decide if you want the frequency axis in the graph to
be linear or logarithmic.
Logarithmic is often the most natural choice since each octave (doubling
of the frequency) is then represented by an equal distance on the fre-
quency axis.
5. Click OK to close the dialog.
6. Select 3D Frequency analysis from the Analysis menu.
The wave is analysed and the graph opens in a new window.
The frequency graph shows you how the different fre-
quency components vary over time. A high “mountain”
means that this frequency is very prominent at that partic-
ular time.
Adjusting the view
There are a number of settings you can make that affect
the way the graph is displayed.
1. Either select “3D Frequency analysis options…” from
the Analysis menu, or double click directly on the graph.
Click on the Style tab.
2. Decide whether you want the graph to be in color,
grey scale or black and white.
3. Decide whether you want to use a change in color to
represent the amplitude (the height of each mountain de-
termines its color) or if you want it to represent frequency
(the frequency spectrum is drawn in colors ranging from
red to purple).
4. Decide on a background color (black or white).
5. To view the effect of your changes, click Redraw.
!
The length of the selection affects the accuracy of
the analysis. For short selections the result will be
very detailed. For longer selections (over a minute or
so) it will not give equally detailed results, since the
harmonic content might vary “between the measure
points”, which is then not shown in the display. You
might for example make a separate analysis of
the at-
tack (beginning) of a sound, since the most drastic varia-
tions usu
ally occur there.