Simulation Techniques: Acoustical Engineering via Various Expansion Techniques

This article is one of those reference readings that reflects René Christensen's unique ability to clarify underlying problems before trying to engineer broader-level solutions. When dealing with design decisions in acoustics, one should consider analytical approaches, he explains. The so-called “Expansion Techniques” shown in this article have a focus on circuit implementations of physical problems in microacoustics and electromagnetics.

This latest Wavecor soft dome tweeter is specifically intended for car audio applications. Like other models, the new 4Ω TW030TU03 includes a 30mm wide surround with a precision-coated graphene-reinforced cloth diaphragm optimized for high-frequency cutoff above 20kHz. The design also features internal chambers below the dome and surround edge, dual neodymium magnets vented into a damped rear chamber, copper-clad aluminum voice coil winding with a vented voice coil former, and flexible lead wires.

Scan-Speak has been working with Composite Sound to develop a generation of metamodal thin-ply carbon diaphragms (TPCDs), engineered to fully replace the almost impossible-to-source and extremely expensive beryllium domes. The Scan-Speak D2908/716000 1” Revelator TPCD tweeter, which replaced the Revelator D2908/714000, now includes a new 1" TPCD metamodal diaphragm, combined with the patented Scan-Speak Symmetrical Drive SD-2 neodymium motor structure.

Acustica Beyma continues to expand its range of products from solid foundations in professional audio, now also to emerging installation and even high-fidelity applications, while implementing a solid environmental stance. This 1.4" throat, high-power-handling compression driver, characterized with the new Beyma 60° × 40° TD-1464P horn, is targeted for mid- to large-venue PA systems and is one example of those efforts.

A fresh, analog-friendly electronics project, this article proposes one of many DIY examples from the author’s Audio Circuits Cookbook. An excellent way to dive into the art of guitar effects and tone shaping, benefiting from the experience of someone who's been doing this since the 1960s, this article shows how to rewire a typical guitar using a Fender Telecaster as the example, and how to build small high-gain circuits like a fuzz-tone or a compressor, to great effect.

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.

Voice Coil April 2025 is our Cable and Connector focused edition, and includes an updated vendors directory, plus a special Measurement Microphone Directory. And for this issue, Vance Dickason offers a triple dose of his Test Bench, with the new Beyma CD-314Nd/TI compression driver and horn, the Scan-Speak D2908/716000 TPCD metamodal 1" dome tweeter, and the Wavecor TW030TU03 graphene-coated soft dome tweeter.

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.