Patent Review: Vertically and Horizontally Balanced Subwoofer

The patent reviewed here was granted to inventors Robert G. Johnston (Amprior Ontario, CA), and Sanford M.Gross (Owings Mills, MD), respectively the head of engineering of GoldenEar Technology, and one of its co-founders. The patent describes a subwoofer with two drivers on each side plus one passive radiator facing up and one passive radiator facing down. The passive radiator facing down effectively couples acoustic energy at very low frequencies into the floor.

James Croft explores patents granted to Mattias and Timothy Scheek, on behalf of Mayht Holding B.V. Our readers will recognize the name from the April 2022 announcement of the acquisition by Sonos of Mayht Holding BV, for "$100 million in existing cash on hand.” Having followed their work through a number of patent publications, Mayht's technology triggered Croft's curiosity, for its unconventional structural designs, appearing to represent fresh thinking. This article was originally published in Voice Coil, July 2022.

Happy 36th Anniversary Voice Coil! The November 2022 issue of Voice Coil once again celebrates the launch of this periodical as an information resource for the loudspeaker industry. Also, this month, Mike Klasco writes about technologies and solutions to enhance low-frequency performance, and James Croft reviews a recent patent awarded to Panasonic for a loudspeaker arrangement for a Near to the Ear Subwoofer in a car seat. For this month's Test Bench, Vance Dickason characterizes the 6CXN36 coaxial 6.5” pro sound driver from B&C Speakers, and Wavecor’s FR4X-6WA01 compact oval full-range driver. Now available in print, digital and online.

Sometimes James Croft reviews patents that are hard to understand how could they possibly have materialized. This patent describes a “System and Method for Improved Audio Perception” and was granted to Yair Raz (inventor) on behalf of Innovo IP, LLC (Aventura, FL). The “invention” describes “methods of Audio Signal Personalized Enhancement for optimal listening to music using a combination of hearing test, audio signal compensation, and signal processing algorithms. A description that could easily be applied to dozens of currently available products. This article was originally published in Voice Coil, November 2016.

Nanusens has had its first patent granted in the US, with filings in other countries underway, and has more patents in the process of being applied for. These all protect the company's innovative technology of building nanoscale structures within a standard CMOS metal layers to create novel NEMS (Nano Electro Mechanical Systems) sensors. Nanusens recently appointed Dr Graham Hine as Chairman with the goal of driving growth and fund raising for the nanosensors company.

In this article, James Croft reviews a generic “Loudspeaker” concept patent, granted to Teppei Yamada, of Tokyo, Japan, on behalf of Zorzo Co., Ltd. and which describes a somewhat surprising concept of a loudspeaker that includes a hermetically sealed enclosure, with a driver outside of an enclosure and a second driver inside, with a pipe communicating between the two drivers. The second driver is configured to output a signal of opposite phase to that of the first driver. This article was originally published in Voice Coil, October 2016.

In this article, James Croft looks at a patent awarded to David Russell (Toronto, CA); and John French (Caledon, East, CA) on behalf of Audera Acoustics, Inc., Schomberg CA. The patent describes a generic acoustic high displacement transducer system, containing a diaphragm position sensing module, a controller with a transmitter, so that the voice coil moves at least partially in response to the control signal.

This article reviews a patent originally granted to inventors Philip R. Clements; (Tempe, AZ), Boaz Shalev; (Needham, MA), and James Joseph Croft, III; (Bellevue, WA), which has now expired. The patent describes a low-frequency transducer system with a multi-compression chamber, where an inverse horn structure is employed in combination with a resonance-distortion filter chamber. This was the third patent granted on Atlantic Technology’s low frequency system known by the trademark name H-PAS (High Pressure Acceleration System). This article was originally published in Voice Coil, September 2016.

John Melanson, senior technical fellow at Cirrus Logic, has been granted his 500th US patent, an achievement that places him among the world’s most prolific inventors. The Academy Award-winning engineer’s core contributions are within the field of audio and electronics, particularly the analog and mixed-signal technologies that have helped transform the analog world around us into the digital signals at the heart of today’s most advanced products.

This review looks at an independently patent submitted in 2013 and awarded in 2016 to Jack Nilsson (Canton, OH), describing a system and method for an audio system including a first speaker that reproduces sounds in a first frequency range and a second speaker that reproduces sounds in second frequency range. As James Croft comments, the patent is interesting in its purposeful application of breaking currently established rules and may be useful in certain applications or environments. This article was originally published in Voice Coil, August 2016.