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EQ Copy
Note that the equalizer adjustments adjust the EQ set
that is selected for the currently selected format. You can
hit the format tab to quickly view which EQ set is
currently being controlled. The Copy button copies the EQ
settings for a particular audio channel in any EQ set to
another channel in any EQ set. Since the different audio
channels typically require approximately the same
equalization, one channel can be set up and then copied
to other channels as a starting point. Those channels are
then fine tuned as required.
Press the “Copy” button. The EQ Copy dialog opens.
Select the Source “EQ Set”.
Click the “ + ” button to the left of the EQ Set symbol
in the lower left portion of the window. The icon will
explode to the view shown above where each audio
channel is visible.
Click on the speaker corresponding to the channel that is the source of the EQ copy. For example, if you want
to copy the left channel equalization to the right channel, click the left speaker. “Select Channel Destination”
will appear in the destination area of the window.
Select the “EQ Set” destination (often the same as the source) and the channel destination. A Copy button will
appear. Click the Copy button to copy the equalization from the source channel to the destination channel.
Note that you cannot copy a channel to itself and you cannot copy a full band channel to the LFE (Low
Frequency Effects or subwoofer) channel.
Press “Close” to close the copy window.
Channel Equalization Procedure
A suggested procedure of equalizing a channel is listed below. Your theater may use a modified or different
procedure.
Position the RTA microphone in the auditorium as specified by SMPTE 202M-1998 (about 2/3 of the way back
from the screen and 2/3 of the way from a side wall of the auditorium). The microphone is normally 1.0 to 1.2
meters (3.3 to 4.0 feet) from the floor, or “ear level” for a typical audience member.
Plug the microphone in to the PA or CAL microphone input of the JSD-100. Set the RTA input to the
appropriate microphone input.
Press the Curve File button and select the appropriate curve file (such as x-curve.txt). This sets the limit lines
on the RTA display.
Set the front panel fader level to 7.0.
Turn amplifier gains all the way down. Move the gain control on the equalizer all the way down. This adjusts
the “output trim” on the channel that is being adjusted. There are separate output trims for each audio
output. Note, however, that the individual channel output trims are in common to all the equalizer sets.
Adjusting the gain control on equalizer set 2 also adjusts it on equalizer set 1.
Select the channel to be equalized, pink noise, and generator to send pink noise out the appropriate output of
the JSD-100.
Slowly increase the power amplifier gain to full while watching an SPL meter at the RTA microphone position.
Do not increase the level above 85dB SPL.
Adjust the gain control (output trim) on the equalizer until a measured sound level of 85dB SPL or 82dB SPL for
surround channels is present.
Adjust the RTA gain to put the mid-band level at 0dB.
Adjust the equalizer controls to put each frequency band within the curve limits As discussed above, the decay
time should be increased for more stable and precise measurement as you close in on the final equalization.
