Auto Feedback Reduction (Afr) Function; Using The Afr Function - Yamaha Acoustic User Manual

Auto Feedback Reduction (AFR) Function

The MAGICSTOMP is equipped with a highly sophisticated Auto Feedback Reduction
function (AFR) to eliminate feedback (howling).
* In this case, "Feedback" is when a specific frequency produced by the amplifier causes the guitar to resonate
uncontrollably, creating a howling sound.
The MAGICSTOMP's AFR function uses a notch filter, which cuts the frequency that is
causing the feedback, to eliminate feedback. A maximum of five notch filters can be set
and operating at the same time.
How the –, AFR/ON/OFF, + Switches Function
The AFR function can only be active when the patch's
effect type is set to "AcousticMulti". If the AFR function is
switched ON, the
Switch operation as described below, will only result in
switching the patch ON/OFF if a patch using another ef-
fect type is selected, or the AFR function is switched OFF
(the edit icon is displayed) even if the patch's effect type
is set to "AcousticMulti".

Using the AFR Function

The procedure required for switching the AFR function ON/OFF differs in the Up/Down Mode and in
the Performance Mode.
q
When feedback occurs in the Up/Down Mode press the AFR/ON/OFF switch,
and when in the Performance Mode press the switch that corresponds to the
currently selected patch (–, AFR/ON/OFF, +).
The MAGICSTOMP will automatically identify the frequency causing the feedback and activate
an unused notch filter. When the filter identifies the problem frequency, the display will appear
similar to that shown below and then return to its previous condition.
To indicate that the AFR function is active, the AFR/ON/OFF switch's lamp will flash when in the
Up/Down Mode, while in the Performance mode, the switch's lamp (–, AFR/ON/OFF, +) for the
currently selected patch will flash.
If the filter fails to be set, the following display is shown before returning to its previous condi-
tion.
22
edit icon will be shown in the display.
• The AFR function is active
• The AFR function is inactive