Dayton Audio OmniMic V2 Precision Measurement System - Manual (Page 22)

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Obtaining your Typical ("Average") Response Measurement
To make up your average curve, play one of the "Short Sine Sweep" responses from the speakers while measuring with
the Frequency Response tool. Set the "all, blended, only to" buttons to "all" (which will include all reflections in the
results) and the smoothing to 1/6th or 1/12th octave. Put the microphone at the first listening position and click on "New
Average" (or tap the spacebar on your keyboard). If you want to emphasize this, say, 5 times as much as the least
important seat, click or tap 5 times while there. Then repeat for all seats of interest. In a large theater, you can save time
and just do this for a sampling of seats in different general areas. The red curve on the graph that appears is the
"Average" response curve that you will want to equalize for. You may want to save this average response curve to disk
using the "File>Save Avg Curve" menu, which will allow you to reload it later should you wish.
Getting the Equalization Curve
Now, bring up the Equalizer Configuration form by clicking the "Main Math>Show Equalizer" menu. A small form will
appear.
In the form, you choose:

the frequency range over which you wish to equalize

the type of target curve: a flat line with a specified slope; or a curve from a text FRD file (which you can select or
even create on the fly from an included text editor). The target curve will appear on the Frequency Response
form in a thicker grey line.

the amount (in dB) to offset the target curve. You would normally set this one (visually, watching the grey line and
the red Average curve) to the position that requires the least work of the equalizers to approximate the target
curve.

The offset will normally be based on the response within the optimization range, you can also choose to "lock" it
so that frequency range selection doesn't further affect it or so that the same target can be used for different
speaker channels.
You would typically equalize an in-room response to approximate some "target" curve, which is the response
shape you wish the system to have. In many cases, the target will be a "flat" response, but possibly you may find
that using a "house curve" or a response with a slight downward slope will sound better with recorded music or
video programs. OmniMic makes this easy to achieve and to vary as desired. Equalization may only be desired
at bass frequencies in some systems.
If you need to generate an FRD or text file of the response curve, then at this point just click the "Make EQ
FRD file" button and tell the program where you want to store the file. This would be the approach to use if you
have only a "graphic" type equalizer available. Use the file to see the response your equalizer should ideally be
set for; approximation of this curve is usually sufficient, great detail in setting is not needed and is seldom
recommended.