All items in category Magazine Articles
Innovative Wi-Fi Streaming for High-End Headphones
by Christoph Apel

Innovative Wi-Fi Streaming for High-End Headphones

As digital integration deepens across all aspects of life, consumers increasingly seek audio experiences that blend seamlessly with wireless connectivity. As a leading developer in the audio streaming sector, StreamUnlimited is continuously pushing the boundaries to transform traditional audio systems into smart, connected devices without sacrificing sound quality. Recognizing this trend, StreamUnlimited developed an innovative Wi-Fi solution tailored for both high-end and mainstream headphones, redefining the wireless listening experience.
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Book Review: Zoran M. Dukic’s High End Tube Amplifiers Designer Tool Box
by Jan Didden

Book Review: Zoran M. Dukic’s High End Tube Amplifiers Designer Tool Box

This extensive, 428-page, self-published hardcover book, is much more than another publication on tube amplifiers. As Jan Didden discovered, this book contains all the knowledge needed to check how an input low-pass filter must be dimensioned, how to investigate the different resistor types and their properties, capacitor types, which tubes to use, how to bias them, and construct the load lines, and even how to design low-noise power supplies. A one-stop resource for tube-based audio power amplifiers, and clearly a work of love!
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Fresh From the Bench: Sony MDR-M1 Closed Monitor Professional Headphones
by Brent Butterworth

Fresh From the Bench: Sony MDR-M1 Closed Monitor Professional Headphones

Intended to become a new studio stalwart replacing Sony's MDR-7506 headphones, which have been a fixture in recording and radio studios for decades, the new MDR-M1 headphones retail for two and a half times the price. Sony reexamined and improved upon all aspects in the new MDR-M1 headphones and added a few improvements according to today’s high-resolution standards for mixing and mastering. Brent Butterworth compares the new MDR-M1 to the MDR-7506 and the AKG K371.
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Spikes & Isolation: The Art of Speaker Decoupling for Optimal Audio Performance
by Dave Morrison

Spikes & Isolation: The Art of Speaker Decoupling for Optimal Audio Performance

This contributed article by IsoAcoustics' founder and president is an interesting piece that sums up his vast experience in the field, working with professional audio engineers, loudspeaker designers, and music lovers all over the world. The article explores how speakers physically interact with their supporting surfaces, the key factors that affect speaker decoupling, and the pros and cons of many common isolation approaches.
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Getting Out of the Ear: The Evolution of ANC Technology in Hearables
by Alex Bonnet and Eric Benhaim

Getting Out of the Ear: The Evolution of ANC Technology in Hearables

This deep dive article from Alex Bonnet and Eric Benhaim - Orosound’s acoustics technical lead and chief technology officer, respectively - offers a unique perspective of the challenges associated with the increasingly popular open ear form factors. Extensively familiar with product implementation challenges, the two authors address the specificities of loose-fit and open-ear designs, and the potential of AI-based ANC technology for the future of hearables.
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Modern Op-Amp Distortion Tests: Part 2 — A Few More BJT Types and JFET Devices
by Douglas Self

Modern Op-Amp Distortion Tests: Part 2 — A Few More BJT Types and JFET Devices

Many new op-amp types have appeared in the last decade, and Douglas Self thought it was time to evaluate those for distortion performance. In Part 1 of his article, he measured BJT-input devices using a similar protocol for five different loads and testing for basic op-amp distortion in favorable circumstances. In this second article, the measurement of BJT types is concluded, and he moves the JFET types to the test bench.
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Modern Op-Amp Distortion Tests: Part 1 - BJT-Input Devices
by Douglas Self

Modern Op-Amp Distortion Tests: Part 1 - BJT-Input Devices

Douglas Self has been using a tried-and-true palette of op-amps in his designs. Because many new types have appeared in the last decade, he thought it was high time to evaluate those for distortion performance. In Part 1 of this article, he examines BJT-input devices using a similar protocol for five different loads and testing for basic op-amp distortion in favorable circumstances. FET input op-amps are investigated in Part 2.
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Speaker Box Alignments from Numerical Optimization - The Quasi-Chebyshev Alignment
by Lars Risbo

Speaker Box Alignments from Numerical Optimization - The Quasi-Chebyshev Alignment

After seeing many speaker designers returning to trial-and-error approaches that seem to forget the historical work and analytical approach, Lars Risbo decided to explore numerical optimization to synthesize attractive alignments both for reflex and passive radiator box types. This reference article basically expands on Claus Futtrup's "Loudspeaker Bass Reflex Alignments" article series published in audioXpress, and expanded with dedicated articles in Voice Coil.
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Simulation Techniques: Perturbation Methods in Audio Engineering
by René Christensen

Simulation Techniques: Perturbation Methods in Audio Engineering

Standard simulations are closely tied to the analytical framework much more than the numerical. Simulation software gives insight into physical products that could not be achieved otherwise, often leading to less attention being paid to analytical methods and descriptive mathematical expressions related to the physical application. This article explores an analytical approximation method described as a perturbation approach.
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Fresh From the Bench: Purifi 1ET9040BA Balanced Class-D Amplifier Module
by Jan Didden

Fresh From the Bench: Purifi 1ET9040BA Balanced Class-D Amplifier Module

The Purifi 1ET9040BA balanced Class-D amplifier module, a Bridge-tied-load (BTL) output stage, is the second product in the company's Eigentakt range. Following a conversation with members of Purifi about the amplifier's audio performance being hard to measure even with the best available test equipment, Jan Didden, in collaboration with Rens Tellers, took up the challenge, with invaluable support from Audio Precision's parent corporation Axiometrix.
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