Ostfildern / Munich, Germany, December 11th, 2014
Today,the German Patent And Trademark Office granted Barth Acoustic GmbH a patent on his cardioid directional loudspeaker technology:
Particular passive membranes located on the rear of the cabinet also emit sound from the rear of the cabinet. In doing so, phase shifting leads to effective sound cancellation on the rear of the loudspeaker. As a consequence of the drastically reduced diffuse sound level, speech intelligibililty and naturalness of music reproduction is immensely increasing. A massiv benefit especially in places with highly reflective surfaces or long reverberation times.

Neither DSP nor addtional amplifier channels are necessary. This technology  works down to the fundamentals, so neither highpass-filters nor other provisions need to be used to limit the cone excursion. On a similar cost level with regard to conventional loudspeakers of comparable quality, users, contractors, operators and owner-builders obtain a true and sustainable added value.