For more information on feedback suppression, readA Detailed Look at Feedback Prevention & Suppression.

The AFS2 algorithm watches incoming audio and monitors for tell-tale signs of feedback. Feedback typically behaves in a very specific way, and when AFS detects that behavior it quickly places an extremely narrow notch filter at the problem frequency. This suppresses the feedback while staying narrow enough to not adversely affect the rest of the audio in the sound system.

It analyzes that feedback in a matter of milliseconds to determine its specific frequency and corrects that output from the PA using very narrow frequency notches—i.e., it cuts a very specific range of frequencies from your output signal so the feedback disappears.

If the range of frequencies cut from the output signal is too wide, sound quality could be affected. That’s why the proprietary AFS algorithms cut only what’s needed, in notches as narrow as 1/80th of an octave, ensuring optimal frequency response without the possibility of feedback.

Before the human ear can even begin to sense it, the dbx AFS2 hears the feedback creeping up in the signal.

600

-8

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Frequency (Hz)

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nit

ude

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Filter Width Comparison Chart

AFS

Competitor

1/3 Octave GEQ

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How it works:

Key dbx AFS2 features:

Input Signal MetersAccurately monitor input signal levels with five segment LEDs per channel plus red clip LED indicator.

Wizard Setup FunctionsThe AFS2 Feedback Supression Wizard makes setup easy and approachable for users with varying levels of technical know-how. Select Application-specific filter types for Speech, Music/Speech, and Music and the number of fixed or live filters up to a total of 24.

Channel BypassIsolate problem channels with the option to bypass Channels 1, 2, or both.

Notch Filter IndicatorsVisually monitor the number of notch filters applied on each channel.

Keywords: audio, feedback, feedback prevention, feedback suppression, feedback flow, audio engineer, Harman Innovation, AFS, AFS2, dbx, EQ

HARMAN (NYSE:HAR) (www.harman.com) designs, manufactures and markets premier audio, visual, infotainment and integrated control solutions for the automotive, consumer and professional markets. With 15 leading brands, including AKG®, Harman Kardon®, Infinity®, JBL®, Lexicon®, Mark Levinson® and Revel®, the Company is admired by audiophiles, musicians and the entertainment venues where they perform. More than 25 million automobiles on the road today are equipped with HARMAN audio and infotainment systems.

For more audio innovation insights go to harmaninnovation.com

Eradicate Feedback Before It Starts with the right equipment, it’s easier than you think

Harman products with the AFS2 algorithm

dbx DriveRack PA2

dbx AFS2

Digitech Vocalist More coming soon

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