DEOX DEQX-Cal, Installer Manual

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Calibration Wizard
Clicking Next opens a window initially showing the impulse-response of the speaker(s) as
measured. This impulse-response is shown on the anechoic tab of the window.
Unless you measured the speaker in an anechoic chamber, the impulse-response as measured
will include room reflections. In order to remove these room reflections and thus provide a
correction of the speaker by itself, it is necessary to ‘window’ or ‘truncate’ the impulse-response.
To do this, move the right marker to just left of the first reflection, as per the figure below (the left
marker is fixed at 0 milliseconds). In the figure below, the signal received directly from the
speaker was received at about 5 milliseconds and the first reflection was received at about 9.8
milliseconds, or about 4.8 milliseconds after the start of the direct signal.
By truncating the impulse-response at 9.7 milliseconds (as noted in the top right corner of the
chart), only the signal received directly from the speaker will be included in the measurement
used to create the speaker correction.
Clicking and dragging moves the marker. Hint – it may be easier to identify the first reflection if
you zoom in on part of the window.
Use the icon to zoom in.
When the marker is moved the ‘windowed’ response curves (on the Smoothed Measurements,
Crossovers and Limits tabs) are automatically regenerated to reflect the new location of the
marker.