The Latest in Wireless Earbuds and Hearables Innovations in audioXpress April 2025

audioXpress April 2025 is now available and includes a comprehensive Market Update on Wireless Earbuds and Hearables, covering AI, Sensors, how Wi-Fi streaming is possible in headphones, and more. René Christensen explains Expansion Techniques for Acoustical Engineering, Ethan Winer writes about Built-In Guitar Effects, and Vincent Thiernesse shares his incredible single control Low-Frequency Hybrid Crossover. Don't miss also Paul Marchese's Primer on Class-D Amplifiers, and Richard Honeycutt's article on Silvertone guitar amp circuits.

In this December 2024 issue there's a new DSP product review of the Marani Pro Audio MIR260A outboard processor, and Lars Risbo shares his expertise in Numerical Optimization applied to Speaker Box Alignments. Essential resources are the updated directories of Test and Measurement and of Simulation and CAD Software vendors. On Test Bench, Vance Dickason characterizes the Faital Pro HF110 1" Neodymium Motor Compression Driver and the SB Acoustics Satori MR16TX-8 6.5" TPCD Midrange.

There's a lot of knowledge in audioXpress September 2024. There's a residential installation and home theater Market Update, and a review of the Dayton Audio iMM-6C USB-C Test Microphone. George Ntanavaras shares what he learned using AKABAK simulation software, and Charlie Laub explains all about Derived from Elliptic crossover filters. Read Jan Didden's interview with Joachim Gerhard discussing Low Noise Phono Stages, and learn how to build a Moving-Coil Phono Preamp designed by Sam Dulaney. And much more.

audioXpress August 2024 features our traditional Acoustical Solutions Round-Up, while Active Acoustic Enhancement Systems are also discussed in the Sound Control column. Oliver Masciarotte reports from AXPONA 2024, Philipp P. Klose reviews the new IK Multimedia ARC Studio solution, and Brewster LaMacchia expands on alternative power schemes for audio applications with A2B. On audio electronics, Charlie Laub explores Notch Filters, and Todd Schneider details his High-Fidelity Active Direct Box project.

In this article, Vance Dickason highlights the possibilities for a two-way DSP filter design using the CrossLite+ software package. Under development by the Brazilian pro audio company since 2009, CrossLite+ is a dual-channel FFT analyzer that will function with basically any USB-type recording interface. CrossLite+ is intended primarily for product development of DSP-powered pro speakers and for use in live sound PA systems. And measured data can also be imported from other analyzers such as the CLIO or Klippel This article was originally published in Voice Coil, December 2021.

In the December 2021 edition of Voice Coil, Vance Dickason details the possibilities of the CrossLite+ DSP filter software, while James Croft reviews an interesting invention to improve the bass response in automotive audio applications. And this edition includes an updated measurement microphone directory, and two interesting low-frequency drivers on Test Bench, with the Dayton Audio Epique MMAG E150HE-44 subwoofer, and the powerful 10NW76 high-SPL woofer from B&C Speakers.

Passive crossover filter networks for multi-way loudspeakers generally require a resistive termination for optimum performance. The driver itself generally presents a reactive load. Inductive rise with frequency above resonance of the loudspeaker electrical impedance is semi-inductive due to eddy current losses. The L2/R2 impedance model represents the electrical impedance as seen by the amplifier output. An improved compensation network can be realized by using the analogous circuit “dual” of the L2/R2 model. This represents a dramatic improvement to the basic two-component Zobel network and compensates for the non-ideal semi-inductive behavior of the loudspeaker driver across the entire frequency band.

The March 2020 edition of Voice Coil is now available online and in print. In this edition, Vance Dickason gets hands-on with the Audio Precision APx500 Flex Audio Analyzer, Mike Klasco writes about Loudspeaker Enclosure Materials, and James Croft explores a new patent of a novel orientation of a cardioid speaker design. And in Test Bench, Dickason characterizes a home audio transducer from Eastech's Punktkilde line, the cosmetically pleasing AUGWL0016-JN02 6.5” midbass driver.

McIntosh Labs has been perfecting vacuum tube amplifiers since the 1940s and solid-state amplifiers since the 1960s. From that heritage, McIntosh now announced the MC901 Dual Mono Amplifier, a truly one-of-a-kind monoblock that is also two amplifiers combined into one, with each amplifier boasting differing design philosophies including a 300-Watt vacuum tube amplifier attached to a 600-Watt solid state amplifier on one unified chassis.

Sonus faber announced the launch of their Olympica Nova high end speaker collection, with seven completely new models, at the 16th Annual Rocky Mountain International Audio Fest (RMAF). The newly expanded Olympica Nova series embraces the authentic values that inspired the original Olympica line while adding a substantial amount of freshly developed technology, from new drivers and crossovers, to a new cabinet structure and internal volume tuning, and a new exterior look.