USL JSD-60 Manual - Manual (Page 31)

Page 31
Filters Tab
The channel filter settings are available in the filters tab. A filter response plot is displayed and updated when the
settings are changed.
The channel filter is typically not used (set to Off). A couple uses are describe below.
In a 7.1SDDS auditorium (one that includes Lc/Rc speakers), it is desirable to generate Lc/Rc when 5.1 content
(which does not have these channels) is played. Lc can be generated by mixing L and C on the Advanced tab.
Similarly, Rc can be generated from R and C. To prevent undesirable spreading of dialog, the channel filter can be
set to notch out the dialog frequency range on the Lc and Rc channels.
On the LFE channel, a high pass filter may be added with a Q greater than 0.71 to add a “bump” in the low
frequency response. This can be used to slightly extend the low end of the LFE channel.
Channel Selection
A list of channel selections is displayed above the filter response graphic plot. This plot focuses on the channel
filter parameters within the audio processing chain. The final output will have additional filtering, equalization, and
crossover settings applied. For instance on the LFE the output will have a low pass applied and higher frequencies
will be significantly attenuated.
Zoom
A zoom control is used to expand the plot view to review details in the filter settings. As the zoom control is
increased, the plot will be centered to within the graphical plot area.
Filter Type
The filters can be cascaded to create a band pass filter or placed in parallel to create a notch filter. There are two
filters that are used to create a low pass, high pass, notch, band pass, and off. For the high and low pass
arrangement, a filter is removed (turned off) in the audio processing stream.
Low/High Filter Parameters
Each filter has frequency and Q settings. For a band pass filter, the low pass filter will set the upper frequency
limit, and the high pass filter will control the lower limit.