thomann t.racks FIR DSP 408, User Manual

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Range Meaning
Display area Use the radio buttons ‘ Mag’ or ‘Phase’ to switch the diagram from Cartesian coordinates (level vs.
frequency) to polar coordinates (angle vs. frequency).
Use the radio button
‘SHOW ALL EQ’ to display the parameters for all nine frequency bands.
Control area For each output channel and all nine frequency bands (numbered with ‘PEQ’ ) you can enter the
parameters of the parametric equalizer directly as numerical values in the left part of the window:
Centre frequency, filter quality, slope, filter type. With the ‘Bypass’ button, the equalizer for the
respective frequency band and the respective channel can be bypassed temporarily.
In the middle part of the window (
‘PEQ Parameter’ ) you can adjust the parameters centre frequency,
filter quality and slew rate with the faders and the arrow keys on the PC keyboard. The setting refers
to the frequency band that is highlighted green in the left part of the window.
When the IIR filter is selected, you can select the cut-off frequency and filter type for the low-pass and
high-pass filters. Use the ‘Bypass’ button to temporarily bypass the filter.
If you select the FIR filter, the PC software displays the FIR coefficients. You can select and adjust the
type (low-pass, high-pass, frequency band) and set the cut-off frequency for the high-pass and low-
pass filters. The FIR curve appears with numerous setting options. Here you can select the number of
taps from ‘512’ … ‘1024’ (preset: 512). The FIR filter becomes active when you click [OK] . To import
external FIR coefficients, select for ‘TYPE’ ‘External FIR’ and click on the file to be imported (supported
file formats: csv and txt). The imported FIR-PEQ is displayed immediately in the FIR curve.
Drag the fader in the right part of the window using the mouse to set the level for the output channel.
The ‘Mute’ button mutes or unmutes the respective channel. The ‘Normal’ / ‘Inverse’ button inverts
the phase of the respective channel by 180° when needed.
Operating on the computer
digital speaker management system
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