All items in category Magazine Articles
Patent Review: Acoustic Passive Radiator Rocking Mode Reducing
by James Croft

Patent Review: Acoustic Passive Radiator Rocking Mode Reducing

With the increasing popularity of miniaturized systems, the application of the passive diaphragm radiator, as the acoustic mass component in a bass reflex enclosure, is becoming standard practice in the low-frequency portion of the system. And these systems have a few parameter demands that can exceed the capability of many conventional approaches to passive radiator design. In order to solve those challenges, including rocking modes, Bose proposed an effective design.
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Patent Review: Acoustic Filter for Omnidirectional Loudspeaker
by James Croft

Patent Review: Acoustic Filter for Omnidirectional Loudspeaker

This is an interesting patent awarded to Lakshmikanth Tipparaju, Allan Devantier, William Decanio, and Andri Bezzola, on behalf of Samsung Electronics - effectively the audio research team that Samsung created in Valencia, CA. The industry has attempted to achieve a successful implementation of acoustic radiation closely coupled to a boundary surface for omnidirectional and subwoofer applications - unfortunately, mostly plagued by resonances generated by the waveguide or reflector surface. This new approach appears to be an effective solution.
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Room EQ Wizard (REW) - Looking Back on Audio Measurement Software History
by Philipp Paul Klose

Room EQ Wizard (REW) - Looking Back on Audio Measurement Software History

This article revisits 20 years of Room EQ Wizard (REW), one of the mainstays in the audio measurement tool landscape with a strong user base. What started out as a side project for John Mulcahy, the creator and only developer, evolved to become a very complete and useful suite for both enthusiasts and professionals - a comprehensive set of measurement software tools bundled in a free package. This entertaining history of REW is also a fit way to commemorate the software's 20th anniversary.
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Microphone Array Beamforming with Optical MEMS Microphones
by Michael Tuttle and Jakob Vennerød

Microphone Array Beamforming with Optical MEMS Microphones

This article, written by the experts in optical MEMS microphones from sensiBel expands on the technologies that will undoubtedly contribute to making the next generation of hearables and advanced audio systems. As the Norwegian company enters the market with its first-generation products, the authors explain how 80dB SNR optical MEMS microphones will enhance Microphone Array Beamforming and the different types of beamforming algorithms.
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Fresh From the Bench: Listen SoundCheck and AmpConnect 621 Audio and Acoustics Test Suite
by Rens Tellers

Fresh From the Bench: Listen SoundCheck and AmpConnect 621 Audio and Acoustics Test Suite

The latest version of Listen's flagship audio test software, SoundCheck 21, allowed audioXpress to review also the latest Listen AmpConnect 621 USB-controlled multichannel audio test interface. The innovative algorithms and increased measurement capabilities of this powerful and flexible software, together with the AmpConnect 621 analyzer, combines all the functionality required for audio testing in the lab bench or in the production line. This article was originally published in audioXpress, March 2024.
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Simulation Techniques: Acoustical Shape Optimization for Vibroacoustics Applications
by René Christensen

Simulation Techniques: Acoustical Shape Optimization for Vibroacoustics Applications

Having detailed how formal optimization can be used for product design of audio products such as speakerphones and waveguides, in this article René Christensen explores free-form and alternative optimization techniques where the topology of the geometry is given from the outset. Using practical examples, this article addresses shape optimization techniques, identifying useful types of boundaries and challenges to look out for audio product designs. This article was originally published in audioXpress, February 2024.
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A Visit to Audio Precision to See the New APx516 Analyzer
by Vance Dickason

A Visit to Audio Precision to See the New APx516 Analyzer

Vance Dickason visited Audio Precision's headquarters in Beaverton, OR, where he met with Dan Knighten, AP's Product Line General Manager, to talk about the new Audio Precision APx516 Analyzer. This is a new relatively economical analyzer for the company, with a base price of $6000, which means that the APx516 is ideal for use with remote engineering staff, making it practical for companies to have high-precision test and measurement work being done in multiple locations.
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Simulation Techniques: Room Gain
by René Christensen

Simulation Techniques: Room Gain

Room Gain is a term not used in acoustics textbooks as such. Room acoustics is naturally often discussed in the hifi community, since the room you put your loudspeakers in will heavily influence the sound that reaches your ears, both at low and high frequencies. In these discussions the term "room gain" sometimes comes up. This article was inspired by Erik Wiederholtz (CTO of Perlisten Audio) and his interest in the topic, and he was kind enough to provide measurements and photos from his own listening room for a sealed subwoofer as well as for a vented subwoofer.
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Simulation Techniques: Acoustic Topology Optimization for Vibroacoustics Applications
by René Christensen

Simulation Techniques: Acoustic Topology Optimization for Vibroacoustics Applications

Acoustic topology optimization is one of the most interesting new technologies in vibroacoustics. These powerful tools enable engineers to find optimal solutions to problems related to their specific applications and this article presents multiple examples in different areas. The article, originally published in audioXpress, April 2023, includes several examples of transducer geometries modified via acoustic topology optimization.
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A Look Inside Douglas Self’s "Small Signal Audio Design" 4th edition
by Jan Didden

A Look Inside Douglas Self’s "Small Signal Audio Design" 4th edition

Whether it is power amplifiers, vinyl reproduction preamplifiers, active crossover filters or, as in this case, small-signal circuits for a very wide range of applications, Douglas Self is one of those authors who consistently has produced reference works about technical audio. You may think that as a fourth edition, it would just be a refinement on the three editions that went before it but Self always adds new material and new insights to make it worthwhile to get this new book.
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