## Graph Menu

Show/Hide Grid Ctrl+Shift+G
  Toggle the grid on/off by using this menu entry or the associated shortcut keys.
Frequency Axis Log/Linear Ctrl+Shift+A
  Toggle the frequency axis between logarithmic and linear display. The button on the toolbar provides the same function.
Undo Zoom Ctrl+Z
  Restore the graph axis settings that were in use when the middle or right mouse button was last pressed with the pointer in the graph area. The main application is to undo the last Variable Zoom or Zoom to Area action, but it can also be used to undo a pan or any other action that altered the axis settings since the right mouse button was last pressed in the graph area.
Apply 1/1 Octave Smoothing to Current Measurement Ctrl+Shift+1
Apply 1/2 Octave Smoothing to Current Measurement Ctrl+Shift+2
Apply 1/3 Octave Smoothing to Current Measurement Ctrl+Shift+3
Apply 1/6 Octave Smoothing to Current Measurement Ctrl+Shift+6
Apply 1/12 Octave Smoothing to Current Measurement Ctrl+Shift+7
Apply 1/24 Octave Smoothing to Current Measurement Ctrl+Shift+8
Apply 1/48 Octave Smoothing to Current Measurement Ctrl+Shift+9
Apply Variable Smoothing to Current Measurement Ctrl+Shift+X
Apply Psychoacoustic Smoothing to Current Measurement Ctrl+Shift+Y
Apply ERB Smoothing to Current Measurement Ctrl+Shift+Z
  Apply a smoothing filter to the current channel. Repeating the action removes the smoothing. Variable smoothing applies 1/48 octave below 100 Hz, 1/3 octave above 10 kHz and varies between 1/48 and 1/3 octave from 100 Hz to 10 kHz, reaching 1/6 octave at 1 kHz. Variable smoothing is recommended for responses that are to be equalised. Psychoacoustic smoothing uses 1/3 octave below 100Hz, 1/6 octave above 1 kHz and varies from 1/3 octave to 1/6 octave between 100 Hz and 1 kHz. It also applies more weighting to peaks by using a cubic mean (cube root of the average of the cubed values) to produce a plot that more closely corresponds to the perceived frequency response. ERB smoothing uses a variable smoothing bandwidth that corresponds to the ear's Equivalent Rectangular Bandwidth, which is (107.77f + 24.673) Hz, where f is in kHz. At low frequencies this gives heavy smoothing, about 1 octave at 50Hz, 1/2 octave at 100 Hz, 1/3 octave at 200 Hz then levelling out to approximately 1/6 octave above 1 kHz.
Remove Smoothing for Current Measurement Ctrl+Shift+0
  Set smoothing to None. Note that in windows Vista and Windows 7 the Ctrl+Shift+0 shortcut is by default assigned to switching the input language, see http://support.microsoft.com/kb/967893. To remove smoothing either use the graph menu entry, or the smoothing box in the graph controls, or press the smoothing shortcut again - for example, pressing Ctrl+Shift+3 will smooth the data to 1/3 octave, pressing it again will remove the smoothing.

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