Discover New Dimensions of Sound in audioXpress November 2024

This November 2024 issue of audioXpress explores perspectives on signal processing, and sound reproduction. Read a review of the PSI Audio AVAA C214 digital active bass absorber, learn about the exciting possibilities of Audioscenic's Amphi Technology and how to explore the Boundaries of Active Noise Cancellation. J. Martins interviews Andreas Ehret from Dolby Laboratories. Expanding on speakers, we explore Field Coil speaker drivers, Non-Linear Amplitude Modulation distortion and more.

Read the extended Show Report of the 5th International AES Conference on Automotive Audio. Santiago Rayes (GRAS Acoustics) explains the latest advances in Measurement Microphones for Automotive Testing. Reinhold Lutz writes about Eliminating Speaker Doppler Distortion, René Christensen shares an exercise of Double Bass Arrays, and Joerg Panzer (R&D Team) and Patrick Macey (PACSYS) share their Experimental and Theoretical Investigation of an Unusually Shaped Horn. Jan Didden reviews Bob Cordell’s latest book, “Designing Audio Circuits and Systems”.

This article compares motion feedback technologies applied to speakers. A recognized expert in this field, Reinhold Lutz explores how to achieve a nearly perfect electro-acoustic transfer function, including a detailed control strategy of different types of sensors. A great exploration of how a closed-loop feedback system is able to improve loudspeaker linearity.

The March 2024 issue of audioXpress includes an overview of the latest Audio Test and Measurement solutions, a review of the Listen SoundCheck 21 and AmpConnect 621 test suite, and a tribute to 20 years of Room EQ Wizard (REW). Learn how to build a True-RMS Voltmeter and what's behind the myth of Second Harmonic Distortion. Learn how motion feedback technologies can be applied to speakers, and how our hearing process affects our audio listening experiences, and much more. Dive in now!

The principles applied by Dr. Reinhold Lutz's for precise measurement of the sound pressure frequency response in the presence of room modes, are available in its AudioChiemgau Mode-Compensator solution. Jan Didden and Rens Tellers did a basic functional test to find out how well they could make it work and they were pleasantly surprised with the results. This article was originally published in audioXpress, October 2023.

This article discusses how to measure loudspeaker SPL response and harmonic distortion at low frequencies in a standard environment, full of reflections from acoustically hard boundaries (e.g., walls, floor, and ceiling), room resonances, and even ambient noise reducing the dynamic range and accuracy of the measurements. The method combines near-field measurements with two identical microphones. This article was originally published in audioXpress, October 2023.

In the October 2023 issue of audioXpress, Jan Didden visits Dutch & Dutch, Reinhold Lutz shares a practical way to measure loudspeakers in any room with his AudioChiemgau Mode-Compensator, which is tested by Rens Tellers. We have two DIY open baffle projects from Perry Marshall and Charlie Laub, Richard Honeycutt writes about the Western Electric 91E, and Ethan Winer shares his Popping P Filter circuit. In the Sound Control column, Honeycutt explores Passive Variable Acoustics, and Chuck Hansen concludes his article series on Power Transformers. audioXpress October 2023 is now available in print, digital, and online.