Here is what one person said about the Behringer Feedback Destroyer:

Quote: "I use this product during live performances every week. We have a tremendous problem with feedback. With so many frequencies feeding back, this unit unfortunately has a tendancy to knock the sound qualtiy and levels down too much. On one occasion, I yanked the system out during an intermission because 90% of the vocals had been removed, making it appear as though we turned the entire P.A system down. In addition, the ring out can damage your speakers because the system does not respond fast enough to feedback. "Keep a close ear to your tweeters and midrange speakers". The slow response may kill them." End Quote.

Best regards,
Mike