Audio Developers' Secret Weapons, Tips, and Knowledge in audioXpress July 2025

The July 2025 issue of audioXpress includes the AXPONA 2025 Show Report, a review of the Illusonic IAP 8 multichannel audio processor and preamplifier, and an interesting audio processing exploration of Beat Tracking. DPA Microphones shares its CORE+ technology research, and René Christensen offers a deep dive on Microacoustics Modeling. Finally, David B. Soffer explains how to build an Audio Amplifier Power Meter using Arduino, and Richard Honeycutt writes about low frequency annoyance.

As the Revox Group continues to expand its operations and Revox Klangwerk successfully ramps up manufacturing of the Revox B77 reel-to-reel analog recorder, now manufactured in the company's operations in Villingen, in the south of Germany, the company also anticipated an interesting collaboration during AXPONA 2025. Rock star Alice Cooper and Revox have worked together to develop an exclusive, worldwide limited and signed special edition of the new Revox B77 MK III Stereo Tape Recorder and turntables, which were presented at the Schaumburg, IL audio show.

Following a presentation at CES and NAMM 2025, écoute audio showcased the final production samples of its premium TH1 headphones at AXPONA 2025. These highly innovative wireless headphones combine a built-in tube-driven preamp stage featuring a Korg Nutube device, and all the features to be expected from a mainstream product, such as Active Hybrid Noise Cancellation, analog and USB connectivity with support for high-resolution up to 32-bit/384kHz, and wireless Bluetooth with LDAC or AAC. The successful design delivers up to 20 hours of playtime in wireless, tube-driven mode.

Audeze announced the new LCD-S20 closed-back headphones, the first planar model from the Californian company featuring their patent-pending SLAM technology for powerful bass response and improved spatial imaging, along with a new magnetic earpad attachment system. At $499, LCD-S20 becomes Audeze’s most affordable LCD headphones, appealing to a whole new group of content producers, musicians, and music enthusiasts that always admired the planar magnetic products from the manufacturer.

Scheduled for its premiere at AXPONA 2025, the new SCM20ASL compact active speakers, are the main attraction from Acoustic Transducer Company (ATC), and are based on its 50th anniversary ‘Limited Edition’ design. Described as an ideal choice for modestly sized rooms where outstanding musical reproduction is the goal, the new ATC SCM20ASL are 2-way stand-mounts that expand on ATC’s philosophy of combining the best in-house drivers with matched on-board amplification.

Rotel announced availability of its DX-5 Stereo Integrated Amplifier, a compact Class AB powerhouse delivering 33 watts per channel into 4 ohms (25W/channel at 8 ohms) in its new modern style, compact chassis. Powered by an in-house toroidal transformer and high-current transistors, it also incorporates a 768kHz-capable ESS ES9039Q2M Sabre DAC, with specifications promising ultra-low noise (100 dB SNR) and superior reproduction characteristics - as typical of products from the Japanese brand.

Now in its 16th year, AXPONA (Audio Expo North America) will return April 11-13 to the Schaumburg Convention Center offering three jam-packed days of incredible sounds, technology, seminars, networking and the newest products in the industry including a Car Audio Showcase. North America’s largest high-end audio expo will continue to expand in 2025, with 200+ listening rooms, top hifi audio brands, thousands of products and gear, educational seminars and live musical performances.