dbx DriveRack 260, User Manual

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DriveRack
®
DriveRack® 260 User Manual
Detailed Parameters
Section 4
Level (2-8) -12 to 12 dB
Sets the overall level of the selected parametric EQ frequency.
Band 9 Frequency 20 to 20k (High Shelf)
Selects the frequency of the high shelf parametric EQ.
Slope 9 3-12dB/Octave
Sets the slope of the high shelf parametric EQ.
Level 9 -12 to 12 dB
Sets the overall gain of the high shelf parametric
4.2 Feedback Eliminator
The DriveRack 260 offers the exclusive patent pending AFS (Advanced Feedback Suppression) feedback elimination
module. Feedback is caused when a microphonic signal such as a guitar pickup or microphone is reproduced with
amplification and is repeatedly picked up in phase. The AFS uses Precision Frequency Detection and state-of-the-art
processing to determine the exact portions of a given frequency of your feedback that need to be removed (instead
of taking out large sections of your sound). The AFS module of the DriveRack 260 allows the user to optimize the
elimination of feedback. In the past, graphic equalizers were used to eliminate feedback from a system. This was an
acceptable method for eliminating feedback, but when this method was precision tested, the result clearly showed that
a single 1/3 octave EQ slider was removing approximately half of the signal power. With AFS, the module removes the
feedback automatically and the proprietary, precision AFS filters remove only a fraction of the frequency spectrum. The
following diagram shows AFS as opposed to competing, competitive feedback eliminators and conventional graphic EQs:
AFS On/Off
Turns the AFS module on and off. If AFS is Off, the filters are bypassed, and the algorithm is halted (the filters are not
updated). If AFS is On, the filters are active, and the they are updated according to the current selected mode (Fixed or
Live).
Clear Live/All
This parameter clears the filters. If Clear Live is selected, then (if invoked) the live filters are reset. If Clear All is selected,
then (if invoked) all of the filters are reset. When either Clear Live or Clear All is selected, the third parameter row
displays “Clear w/ Data Wheel.” If the Clear field is blank, then nothing is displayed on this row. To clear filters move
the cursor down to the ‘Clear w/ Data Wheel’ row, then turn the Data Wheel. ‘Clearing Filters...’ will appear in the
display.
Mode - Live or Fixed
When the mode is set to Fixed, the algorithm updates only the fixed filters. When the mode is set to Live, the algorithm
updates only the live filters. In FIXED mode, the system is forced into feedback by the user and filters are automatically
assigned to a frequency which is