The Benefits of Using Structure-Borne Sound in Headset Signal Processing

This article details the latest testing strategies for bone conduction technology used in product development for headsets and in-ear devices. It showcases new possibilities for manufacturers to better evaluate device performance, since no appropriate test equipment and methods were commercially available until now.

Building a Haptic Dimension The Science Behind the Taction Transporter

Haptic motors are finding applications in gaming, music, VR/AR, and therapeutic/wellness. The Transporter is a patented transducer that delivers faster more accurate bass and is designed to work with the main audio driver in headphones. It subtly vibrates against the user’s skin to produce an extra dimension that can be described as a high-fidelity extension.

Bone Conductors Going Mainstream

Bone conduction technology that sends vibrations directly to the inner ear, bypassing the eardrums, is seeing increasing use-evolving from its origins in medical hearing devices to mainstream consumer and strategic communication applications. The advantages in open-ear wireless applications have great appeal and the audio industry is responding.

Unusual Tubes

Most aficionados of hollow-state electronics—at least most of the people reading this column—are familiar with the tubes most commonly used in classic or contemporary audio amplifiers. In this article, we explore some of the less common tube types used for audio applications.

Power Transformer Parameters, Selection, and Testing

Part 2 Transformer Cores and Their Construction Methods,  In the second part of this article series, Chuck Hansen details the history of transformer cores and shares information about their various construction methods.

The LNA-100 A Low Noise Amplifier with Filters and a RMS Voltmeter

This project describes the design and construction of the LNA-100 device, which comprises a low noise, high gain amplifier with three different gain settings, six filters for bandwidth restriction, and a True RMS voltmeter that gives a DC voltage at its output.

Using Ultra-Wideband Technology Wireless Delivery of Audio and Multimedia

For tomorrow’s audio and AR/VR devices, Ultra-Wideband UWB) technology provides high throughput, low latency, and low power connectivity for body and personal area networks—even in congested environments. UWB complements Bluetooth and Wi-Fi with high-performance and mobile-friendly short-range wireless connectivity.

Improving Wireless Audio

Part 2 Evolution and Exciting Perspectives, Even though key technologies remain in development, wireless audio evolution beyond Bluetooth offers some very promising perspectives to the industry. Let's look at the efforts and the most promising platforms and technologies for wireless audio.

The Proof Is in the Testing

The Klippel Near Field Scanner (NFS) System was used for the development of Holoplot's X1 Matrix Array compensation algorithms, which was the topic of an article in the September 2022 issue of audioXpress. This joint article by Holoplot and Klippel offers a deep dive into the one of the many benefits of the innovative technology from the Berlin, Germany-based company.

Take the Lead in Acoustics with COMSOL Multiphysics®

Multiphysics simulation drives acoustics innovation by providing insight into every design aspect that influences product performance. The ability to account for coupled physics phenomena lets you predict, optimize, and virtually test a design under realworld conditions - even before a first prototype is built.

Installation, Distributed Audio, and Multiroom

Following the previous Market Update on residential integration, audioXpress explores the latest audio installation trends and solutions. Complementing the residential perspective, the article also addresses the latest audio multiroom approaches and technologies, an area that is clearly on the verge of serious evolution in 2023.

The Home Audio Perspective

Since the adoption of automation systems and home networks, residential integration has evolved gradually to connected systems and is now increasingly associated with the transition to the Smart Home.

Old-Timer, Williamson, and Ultralinear Amplifiers: Families of Hollow-State Power Amplifiers

The July and September Hollow-State Electronics articles examined the distortion performance of the three families of amps. This article recaps those findings and compares them to the last two families, the Williamson and ultralinear amps.

Considerations Concerning RT Measurement

In this article, our acoustics expert explains the history behind the reverberation time (RT) measurement and its importance. He then shares his preferred procedure for measuring RT.

All American Tower Speakers

In this article, our experienced speaker builder takes us along with him on his quest to build a loudspeaker made solely from drivers manufactured in the United States.

Making a DC Power Supply with Audible Benefits: Choosing the Design

Following the two articles exploring multiple power supply circuits with potential for high-end audio applications (audioXpress December 2021 and January 2022), Frans de Wit details a high-quality power supply especially targeted toward preamplifiers, record-players, and other low power appliances.

Triode Common Cathode Stages, the Oracle Equation, and Theodosian Objections

For those readers interested in tube amplification, this article proposes a simplified equation of what might appear to be multiple mathematical factoids into a single concept, intended to help characterize and understand triode circuits.

Replacing IEC 60268-5: The Importance of Measurements

Geoff Hill concludes his discussion about the work taking place on loudspeaker measurement standards, and the progress the International Electrotechnical Commission (IEC) has made with its standards efforts.

The Story of aptX: An Epic Journey

From film sound to radio broadcasts, studios, and finally to Bluetooth and more than 12 billion devices, the successful story of aptX technology is inextricably linked to the history of digital audio. A remarkable corporate journey.

Sumiko Phono Cartridges and RS78 78 rpm Stylus

Sumiko recently announced four new phono cartridges and one new stylus. This article reviews the new Sumiko Olympia and Wellfleet phono cartridges, and the new RS78 stylus, Sumiko's first 78 rpm solution, meeting the needs of many vintage recording enthusiasts.

HDMI Specification 2.1 Improves Home Theater Audio With eARC

The new HDMI standard adds a unique feature to preserve AVR compatibility. In this article, Marshall Goldberg explains how Enhanced Audio Return Channel (eARC) works.

The Brioso Speakers - Lively Two-Way Speakers With Transmission-Line Bass

The Brioso uses a Scan-Speak Revelator midwoofer and a Transducer Labs Alumina ceramic dome tweeter in a floor-standing, mass-loaded transmission-line (ML-TL) enclosure. Paul won first place for this design in the over-$200 category in the 2017 Midwest Audiofest (MWAF) event held by Parts Express.

Miking Solo Voices And Instruments- The Mic Choices

Although there are many microphones, from which to choose, you need to consider several important acoustical factors to obtain good results.

The Challenges Of Live Recordings

Making a high-quality audio recording in a recording studio is one thing, but making a similar recording at a live concert has its own challenges. Neville Roberts flies out to Venice, Italy, to investigate.

Comsol Multiphysics Acoustics Module

Making the Case for Acoustic Modeling and Simulation Apps

Acoustics In Performance

In this book, Richard Honeycutt details “all you need to know about good acoustics and sound systems in performance and worship spaces.” audioXpress and Voice Coil readers will be familiar with Richard A. Honeycutt’s writings, including audioXpress’ Hollow- State Electronics column, dedicated to exploring all tube-related electronics, and his Sound Control column, dedicated to everything in acoustics. Richard has also contributed to Voice Coil since 1994, so the author knows his subject matter.

Schiit Audio's High-Value Ideas

Unless you’ve been away from hi-fi for the past few years, you’ve probably heard of Schiit Audio, a high-value brand available at reasonable prices. Over the years, Schiit Audio owner Jason Stoddard and I have talked at trade shows and I recently caught up with Jason to talk about his company.

DIY Tube Amplifier Heat Management Options

The objective of this article is to illustrate some methods to greatly increase the performance and reliability of your DIY tube amplifier. I’m only discussing DIY tube amplifiers since they generate the most heat per watt of audio output and are hopefully of the most interest to you. Most designs that I have seen in audioXpress have the tube and the transformers on top of the chassis and everything else under the chassis. Most of the amplifiers look nice and work okay, but I think there is a better way!

​​​​​​​Thoughts On AES X223 And X241 Speaker Measurement Projects

I have just returned from the recent Audio Engineering Society (AES) 144th International Convention in Milan, Italy, where I was among many colleagues who are trying to solve one of the outstanding problems of loudspeaker drive units today. Namely, being able to trust the measurements that are being presented to us.

Sonarworks Reference 4 Studio Edition- Loudspeaker And Headphone Correction System

Stuart Yaniger takes a look at Sonarworks, a relatively new entry into this market and its main offering—the Reference 4 Studio Edition, which is clearly targeted to studio and mastering use but can certainly be used in home audio setups.