## Overlays Window

The overlays window shows plots for all the currently loaded measurements. It is shown by pressing the Overlays button in the toolbar of the main REW window.

The overlay plots are selected via the buttons at the top of the graph area.

The various graph types are:

SPL
  All the measurement SPL traces
Predicted SPL
  The predicted SPL for each measurement after applying any EQ filters that have been defined for the measurement in the EQ Window.
Phase
  All the measurement phase traces
Predicted Phase
  The predicted phase for each measurement after applying any EQ filters that have been defined for the measurement in the EQ Window
Impulse
  All the measurement impulse responses
ETC
  All the measurement impulse response envelope traces
Step
  All the measurement step responses
GD
  All the measurement group delay traces
RT60
  All the measurement RT60 traces

### Separate Traces

The basic controls for the overlay graphs are described in the main Graph Panel help, but the Overlays window has one additional button.
The Separate Traces button to the right of the graph selector offsets each trace downwards from the preceding trace to make it easier to distinguish individual features when the traces are at similar levels.

### Graph Controls

The SPL graph has controls to apply smoothing to all the currently selected traces, a control to offset any of the traces and a box to select whether data points should be plotted. The trace offset moves the graph position, but does not alter the data so the legend values do not change. If the Add offset to data button is pressed the current offset value is transferred to the measurement data and the legend readings will update accordingly. If Show points when zoomed in is selected the individual points that make up the measured phase responses are shown on the graph when the zoom level is high enough for them to be distinguished (which may only be over part of the plot)

The Predicted SPL, Phase, Predicted Phase and Group Delay overlays also have a smoothing control. The Phase and Predicted Phase overlays have additional controls to wrap or unwrap the currently selected phase traces. The Phase, Impulse, Step and Group Delay overlays have a control to show data points when zoomed in.

Right clicking in the legend area of an overlay graph brings up a small menu that allows all traces to be selected or all selections to be cleared.

Hovering the cursor over the name of a measurement in the legend panel will bring up a tool tip showing the measurement notes.

Help Index