USL JSD-100 Manual - Manual (Page 27)

Page 26
Turn off the generator.
Copy the equalizer settings to the next channel to be equalized using the Copy button, as described above.
Then repeat the process for the next channel.
LFE Equalization Procedure
The LFE or subwoofer channel uses a parametric equalizer instead of a graphic equalizer. When the LFE is selected
in the Equalizer window, the parametric equalizer adjustments become visible.
As with the other channels, start with the amplifier gain all the way down and the equalizer gain all the way
down.
Slowly bring up the amplifier gain control to full without exceeding 85dB SPL.
Adjust the equalizer gain control up until the RTA shows the subwoofer at the same level as the mid-band
frequencies (0dB).
Adjust the parametric filter frequency to the center of the worst peak or dip in the frequency response.
Set the Q to 4, and then adjust the level control to take out the dip or peak. The Q can be increased to narrow
the correction or reduced to make the correction wider. Adjust the level, frequency, and Q for the best low
frequency response.
Select the output tab and click Generator under the center channel slider. At this point, the pink noise
generator should be driving both the LFE and center channels. Select the equalizer tab again.
Adjust the LFE gain and make minor adjustments to the LFE parametric filter to get a smooth frequency
response over the transition into the LFE frequency range. It may be necessary to flip the phase of the LFE
speaker. The phase can be changed on the Outputs tab using the Invert button under the LFE output level
control.
Finally, on the equalizer tab, adjust the LFE gain so the LFE is 10dB above the mid-range frequencies.
Stage Outputs Tab
The stage outputs tab provides a method of trimming the output level of each audio channel, muting the channel,
inverting the phase, or driving it with a generator (pink noise, tone, or a tone sweep). These controls are generally
set one by one from the Equalizer tab. This tab makes all the settings visible at once. In addition, this output tab
allows the user to name each of the channels. The name above each control can be changed as desired. This
information is saved in the JSD-100 and will be restored to the GUI the next time this particular unit is connected
to.
Surround Outputs Tab
The surround outputs tab provides a method of trimming the output level of each audio channel, muting the
channel, inverting the phase, or driving it with a generator (pink noise, tone, or a tone sweep). These controls are
generally set one by one from the Equalizer tab. This tab makes all the settings visible at once. The surround delay
for each channel pair can be adjusted on this screen. In addition, this tab allows the user to name each of the
channels. The name above each control can be changed as desired. This information is saved in the JSD-100 and
will be restored to the GUI the next time this particular unit is connected to.
The surround delay is set usually based on the length and width of the auditorium. Formulas to determine the
surround delay with auditorium Length and Width in meters and feet are provided.
Surround Delay Using Meters
With Length and Width of the auditorium in meters, the surround delay, in ms, should be (L/3)-(W/6)+20.
Surround Delay Using Feet
With Length and Width of the auditorium in feet, the surround delay, in ms, should be set to L-(W/2)+20.