Sabine's single-channel feedback eliminator! A helpful rack unit to prevent feedback, with 20-bit digital conversion and 12 patented FBX filters. Sabine’s robust feedback control algorithm identifies feedback and places super-narrow filters precisely on the ringing tone. Each filter is custom-made at the moment of feedback, and is placed just deep enough to remove the ringing tone, in 3 dB steps.Tested unbalanced inputs and outputs for audio passthrough.