DBX goRack [13/31] Anti feedback

PERFORMANCE PROCESSOR

Anti-Feedback

Feedback is caused when an in-phase audio loop is created between an input transducer (such as a guitar pickup or

microphone) and an output transducer (a loudspeaker). The goRack includes the exclusive AFS™ (Advanced Feedback

Suppression) algorithm to help combat this dreadful phenomenon. The 10 Live AFS filters will automatically detect and

suppress feedback. Just press the ANTI-FEEDBACK button and the goRack will do the rest.

AFS uses precision frequency detection and state-of-the-art processing to determine the exact range of feedback frequencies

to remove (instead of indiscriminately removing large sections of audio). 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 is put up against

precision notch filters, such as those found in AFS, it becomes very evident that using graphic equalizers for this task severely

affects the tone of the system. With AFS, the precision filters remove only a fraction of the frequency spectrum, eliminating the

feedback with far less audible artifacts. The below diagram shows a comparison of filter widths between the AFS filters and

conventional 1/3 octave graphic EQ filters.

Filter Precision Comparison Chart

TIP: AFS works best when the signal entering the goRack’s inputs is sufficient. If the signal level is too low, AFS may be

slow to respond to feedback. See ‘Setting Initial System Levels’ on page 8 for further information on setting the

goRack’s input gains.