Feedback Reduction

NXT speakers suffer much less from feedback when working with a microphone making them ideal for live events and concerts. The unmatched clarity of sound reproduction helps in reducing microphone feedback even in the most difficult of acoustically reflective spaces, such as glass, ceramics and water.

The resistant to microphone feedback is primarily due to the random nature of radiation of the sound from the flat panel speaker. With random vibrations, a feedback loop does not normally develop, since the chaotic sound waves that are picked up by the microphone are less likely to be retransmitted. With conventional cone speakers, the entire diaphragm moves in unity making it easier to for the feedback loop to develop.

With an NlightN Flat Panel Speaker, it is often possible to actually stand in front of the speaker with the microphone on, and not experience any feedback. This is especially important for live performances and Karaoke.

Links

How do microphones work?

How Microphones Work

Avoiding Feedback

Technical Articles

Improvements in Acoustic Feedback Margin in Sound Reinforcement Systems (Pre-Print #4850)

Peter Mapp (Peter Mapp Associates, Colchester, UK) and Christien Ellis (New Transducers Ltd, Huntingdon, UK)

Abstract

Acoustic feedback stability is a fundamental limitation of all Public Address, Sound Reinforcement and Duplex Teleconferencing systems. Over the past 30 years, a number of techniques have been developed to help improve the gain before feedback margin. This paper reviews progress to date and demonstrates that a new class of loudspeaker, the Distributed Mode Loudspeaker inherently possesses a number of characteristics which potentially make it less prone to feedback. Initial experiments are reported which show a 4dB improvement in Feedback Margin without electronic assistance, gains comparable with most other current signal processing techniques.

Presented at the 105th Convention, Audio Engineering Society, 1998 September 26-29, San Francisco

The study report can be downloaded from the internet ($10) at the AES website. Search by Pre-Print number or author name. http://www.aes.org/publications/preprints/search.html

Teleconferencing and Sound Reinforcement Feedback Margin through the Use of DML Loudspeakers (Pre-Print #4978)

Peter Mapp (Peter Mapp Associates, Colchester, UK) and Christien Ellis (New Transducers Ltd, Huntingdon, UK)

Abstract

Acoustic feedback stability is a fundamental limitation of all Public Address, Sound Reinforcement and Duplex Teleconferencing systems. Over the past 30 years, a number of techniques have been developed to help improve the gain before feedback margin. This paper reviews progress to date and demonstrates that a new class of loudspeaker, the Distributed Mode Loudspeaker inherently possesses a number of characteristics which potentially make it less prone to feedback. Initial experiments are reported which show a 4dB improvement in Feedback Margin without electronic assistance, gains comparable with most other current signal processing techniques.

Presented at the 106th Convention, Audio Engineering Society, 1999 May 8-11, Munich

The study report can be downloaded from the internet ($10) at the AES website. Search by Pre-Print number or author name. http://www.aes.org/publications/preprints/search.html

The NXT Technical Review 01, January 2002

Available for internet download at: http://www.nxtsound.com/technology/techReview.php