FBX Feedback Exterminator®

FBX is Sabine’s patented feedback control system. It seeks out and destroys feedback automatically during a performance.

There are up to 10 FBX filters per channel available in the SWM7000 FBX system. These filters are individually assignable as either an FBX Fixed, FBX Dynamic or a parametric filter.


FBX Feedback Exterminator Glossary

FBX Fixed & Dynamic Filters Introduction
There are two types of FBX filters, Fixed and Dynamic. Both operate automatically. There is no audible difference between fixed and dynamic filters in terms of sonic purity; the difference arises in their application.

FBX Fixed Filters
Fixed filters are set automatically during the FBX Setup and will not change frequency until manually reset.

FBX Dynamic Filters
Dynamic FBX filters also set automatically, but can change frequency, on a rotating basis, as the need arises.

Balancing Fixed & Dynamic Filters
Each channel of your SWM7000 wireless receiver offers a total of 10 FBX filters (combined fixed and dynamic), which can be used as needed to exterminate feedback. The default setting of 7 Fixed and 3 Dynamic can be changed to 8 Fixed and 2 Dynamic using the DIP switches on the back of your receiver, or to any configuration using the Remote Control software.

If you follow setup instructions for setting FBX filters, your receiver will automatically exit SETUP mode (enter READY status) after all Fixed filters, and the first Dynamic filter, have set. In the default condition, this means you will have set eight filters (seven Fixed and one Dynamic), with two Dynamic filters still unset and remaining on standby alert. If you wish to set fewer filters, press the READY button before SETUP automatically exits, after you have set enough filters to safely achieve your desired gain level. In that case, in the factory default condition, you will reserve three unset Dynamic filters for standby.

FBX Filter Width
Sabine’s experience and testing with filters and sound quality has led us to decide upon a default FBX filter width of .10 (one-tenth) octave as the optimal notch width, able to eliminate feedback without affecting music programs. If, with all filters properly set, feedback is still a problem, FBX filters may be set to .20 (one-fifth) octave width. This wider filter setting will help to better eliminate feedback trouble areas, but may also affect music programs slightly. Therefore, the wider setting is generally considered to be appropriate where speech (less demanding than music) is the primary application of the Sabine Wireless system. You can globally change FBX filter width by repositioning a rear panel DIP switch, to change from .10 to .20 octave, or by adjusting filter width using the True Mobility® Remote Software (which allows a range of widths from .01 to 1.0 octave). You may also mix filter widths, either by adjusting individual filter widths using the FBX Parameters button in the Tool Bar, or by changing the DIP switch position during setup. The width of any set filter will always be determined by the position of the switch at the time the filter is created.

FBX Filter Sensitivity & Persistence
These advanced adjustments are available only in the FBX Parameters control window. Click the FBX Parameters button in the Tool Bar to access this window.