JBL 260 User Manual

creating feedback. FIXED mode is used before the performance without any input signal. In 
LIVE mode, the live filters automatically detect and remove feedback during the performance. 
When all of the live filters have been used, they begin to round robin. Essentially this means 
that the first filter set is replaced where a new feedback is detected and notched out. This mode 
is useful because feedback frequencies may change as the microphone is moved, and/or as the 
characteristics of the venue change. Note that only the fixed filter settings will be stored with 
the new program. Live filters clear whenever the unit power cycled, the user loads a different 
program, or the user clears the filters using the ‘Clear all Filters’ function.

If Fixed or Live mode is chosen, the text will read “Type.” The options will be Speech, Music 
Low, Music Medium  and Music High. These types pertain to the Q, sensitivity, and algorithm 
type. Values are; Speech (Bandwidth = 1/5 octave and Q=7.25) Music Low (Bandwidth = 
1/10 octave and Q=14.5) Music Medium (Bandwidth = 1/20 octave and Q=29)  Music High 
(Bandwidth = 1/80 octave and Q=116). Note: To guarantee that feedback is suppressed at lower 
frequencies, the AFS may place wider notch filters at these lower frequencies (below 700 Hz).

This will range from values 0-12. The total number of filters is the total number of filters 
available, and the number of live filters will be  = Total Num Filters – Num Fixed. If this is 
changed before the filters are reset, then the filters will be reset one by one as the number 
changes. For example, if the number of Fixed filters goes down, then the last fixed filter set will 
be reset. Likewise, if the number of Fixed filters goes up (and thus the number of live filters 
goes down), then the last live filter set will be reset. The Fixed/Live filter usage will be indicated 
at the bottom of each page of the feedback elimination effect. ‘F’ indicates an available fixed 
filter, and  ‘L’ indicates an available live filter. A blocked out F or L indicates a filter that is set, 
or in use.

This parameter turns the Live Filter Lift on and off. 

This parameter allows the user to setup the box so that the Live filters will automatically be 
removed after a set time (as indicated by the “Lift After” parameter). It ranges from 5 seconds to 
60 minutes. This feature is useful if the microphone being used is moved or the characteristics 
of the venue change over time. As example; a filter placed minutes ago will not be presently 
preventing feedback. This feature removes unnecessary filters from the spectrum to increase 
sonic quality. If the feedback is still there (after the filter is removed), it will catch it and notch 
it out the same. 

This parameter selects the number of filters being used 

The Subharmonic Synthesizer module has been specifically optimized to enhance Bass audio 
material for use in a variety of professional applications, including nightclub and dance DJ 
mixing, theatre and film sound, music recording, live music performance and broadcasting. The 
Subharmonic Synthesizer module’s two separate bands of subharmonic synthesis provide the 
best combination of smoothness and control.
 

Turns the Subharmonic Synth module on and off.