Patent Review: Passive Radiator Structure

This article analyzes a patent awarded in March 2017 to Yeh-Feng Chou (Taiwan), on behalf of Meiloon Industrial Co., Ltd., of a new Passive Radiator Structure, which adds some desirable attributes and improved performance. As the abstract details, the passive radiator structure includes a surround suspension, a frame, and a web-like spider having a plurality of suspension arms integrally extended to between the diaphragm and the frame, which together minimize sound distortion, increase compliance and upgrade efficiency.

After two years with concerts severely restricted due to the global pandemic, music lovers are expected to attend events in large numbers over the coming months. Successfully managing the noise impact from music events is key to encouraging future events. NTi Audio just updated its NoiseScout noise monitoring system to offer live display of the all-important low frequency components of music as well as all the usual broadband parameters.

ACQUA 5.0.100 is the first iteration of the new generation of the well-established measurement and analysis software ACQUA from HEAD acoustics. ACQUA's significantly reworked software structure provides even greater flexibility for voice and audio quality evaluation, while paving the way for future expansions. Designed for the requirements in applications as diverse as communication systems, Bluetooth, ANC headphones, or smart speakers, ACQUA now supports faster hardware configuration, perceived loudness analysis, and MDAQS audio quality evaluation.

Headquartered in the mountain community of Felton, California, the Inovonics engineering team continues to work tirelessly to meet the needs of an increasingly connected broadcast world. Inovonics now introduced the new 551 and 552 HD Radio Modulation Monitors, providing the ultimate choice for advanced FM and HD Radio signal monitoring. Incorporating all the necessary features for station setup, regulatory compliance and remote monitoring, both models are on schedule to begin shipping mid-February 2022.

Sound and vibration specialist Brüel & Kjær has released the new B&K 2245 class 1 sound level meter, providing a complete solution for basic noise measurements, while combining functionality, ease-of-use and versatility. The latest in Brüel & Kjær’s range of iconic sound level meters was designed to instill confidence in professionals whose work involves noise measurement tasks, providing the reliability associated with the brand, while offering the flexibility to work in combination with dedicated mobile apps.

Ported enclosures are known to extend the low-frequency output of loudspeakers by exploiting the Helmholtz resonator effect produced by the compliance of the air inside the enclosure and inertance of the air in the port. This article looks at the problem of port nonlinearity to determine the correct port size, and the acoustic impedance of the port under high air velocity. This article was originally published in audioXpress, September 2001.