Harman Innovation and their new AFS2 algorithm eradicates feedback before it starts. Learn more at www.harmaninnovation.com

1. For more information on feedback suppression, read
A 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
-6
-4
-2
0
2
700 800 900 1000
Frequency (Hz)
Magnitude(dB)
Filter Width Comparison Chart
AFS
Competitor
1/3 Octave GEQ
1100 1200 1300 1400
How it works:
Key dbx AFS2 features:
Input Signal Meters
Accurately monitor input
signal levels with five
segment LEDs per
channel plus red clip
LED indicator.
Wizard Setup Functions
The 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 Bypass
Isolate problem channels
with the option to bypass
Channels 1, 2, or both.
Notch Filter Indicators
Visually 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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