Minidsp equalizer tuning – Dayton Audio OmniMic V2 Precision Measurement System User Manual
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MiniDSP Equalizer Tuning
The OmniMic v4 software MiniDSP Equalizer function allows you to configure parametric filter settings, manually and/or
automatically, and view the result as applied to a Frequency Response in the
The settings you
determine by this method can then be exported in a file from OmniMic, and then imported into the MiniDSP's control
program for downloading to MiniDSP hardware. You can adjust up to 6 of the MiniDSP PEQ or shelf filters at a time, and
then generate a parameter file for use by MiniDSP. Additional filters can be added, if desired in sets of 6 (before or after
the crossover filters, with Mini-DSP's "2-way Advanced" crossover, and some other plug-ins -- see
for details).
For example, for each of 6 sections, you can apply a parametric filter to cut or boost a selected amound (in dB), at a
selected frequency, and with a selected "Q". Q is related to bandwidth. A lower-Q setting means that the boost or cut will
be effective over a wider range of frequencies, while a higher-Q setting will cause the effect to act over a narrower range
of frequencies with a sharper curve.
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 and
MiniDSP make this easy to achieve and to vary as desired. When you adjust the settings for any of the filter sections, its
effect is immediately shown in an additional yellow curve on the plot, along with the unaltered "Average" curve.
When equalizing a room response, one of the errors that users often make is to "over-equalize", making tedious narrow
adjustments to flatten each dip and peak as seen at a very specific listening position. The problem with doing that is that
the response of a speaker and room is extremely position dependent. Ideally, you want an equalizer correction that
provides the closest approach to the desired response for ALL likely listening positions (as well as all sitting positions of
the listener!). This is why OmniMic has you adjust the equalizer based on the shape of the
You can
obtain an overall typical frequency response measurement (an "Average"), as determined at all the listening seats, by
measuring the response at each and clicking the "New Average" or "More Average" button to include that data into the
ongoing Average curve shape (which will show in a red line). If you want to emphasize the response at any particular
seat (such as where you normally sit) to correct better for that position while stll considering the others, click the "More
Average" button several times after measuring at that position. You can alternately load a previously saved Average (or
standard) response curve using the File Menu ("Load to Avg", "Save to Avg"). You can also average in the most recently
added "Added" curve by right-clicking (rather than left-clicking) on the "More Average" button.
To bring up the equalizer control form, use the "Main Math">"Show Equalizer" menu from the Frequency Response
screen. You must have an Average Curve showing to bring up the Equalizer form, which initially looks like this:
Put a checkmark in the box labeled "show parametric EQ filters" and the form will expand to show:
Each Equalizer section can be set for "Manual" or "Auto" operation, or can be bypassed altogether. You can set the
mode of all six sections by using the master ("All") buttons at the top. In order to select the frequency, intensity, or Q of a
filter section, it must be in manual mode. You can adjust all the filters by eye, if you wish, or have the OmniMic software
automatically place and optimize the filters. Or you can set some of the filters only and let the rest be automatically set.
When you select any filter to use the automatic optimization, the form will expand to show additional optimization controls: