All items tagged with February 2025 (10)

You Can DIY: A New Op-Amp for Phono Preamps Part 1 - The Design

July 2, 2025 by Brian Lowe

You Can DIY: A New Op-Amp for Phono Preamps Part 1 - The Design

Brian Lowe (Belleson) developed a unique custom designed transconductance amplifier (Bel Amp) with fully differential (balanced) low noise JFET inputs and current output for phono preamps. This article details the requirements and parameter values, while exploring design options. A second article explains the discrete op-amp design, complete with simulations and measurements.

Test Bench: Faital Pro’s 5PR120 - 5” Pro Midrange Driver

June 17, 2025 by Vance Dickason

Test Bench: Faital Pro’s 5PR120 - 5” Pro Midrange Driver

The Faital Pro 5PR120 is a high sensitivity and high-power handling 5” midrange driver, built on a proprietary six-spoke cast-aluminum frame, with four vents below the spider mounting shelf, and additional cooling provided by a pole vent. It features a curvilinear inverted single piece “bowl” shaped paper cone and black anodized aluminum dust cap. The motor is a FEA-optimized neodymium ring, and driving the cone is a 32mm voice coil wound with round copper wire on a non-conducting Kapton former.

Enhancing Loudspeaker Efficiency and Bl(x) Symmetry with Virtual Voice Coil, Part 1

June 4, 2025 by Dario Cinanni

Enhancing Loudspeaker Efficiency and Bl(x) Symmetry with Virtual Voice Coil, Part 1

This first article in a two-part series details the design and simulation possibilities of the SpeakerLAB software for speaker designers. In this article, the author explores its Virtual Voice Coil (VVC) module, for designing voice coils and predicting audio transducer parameters with maximum accuracy. The detailed analysis also explains one of the keys that allow the accuracy of VVC prediction, given by a complete temperature management involved in loudspeaker calculus.

Unlocking the Future of Wireless Audio: An In-Depth Look at WMAS

June 4, 2025 by Nick Wood

Unlocking the Future of Wireless Audio: An In-Depth Look at WMAS

Meeting the pressing needs for professional wireless microphone applications, struggling with RF challenges, regulatory constraints, and the scarcity of frequency spectrum, 2024 was the year of the first product announcements leveraging Wireless Multichannel Audio Systems (WMAS) technology. In this article Nick Wood (Shure) provides a unique perspective of the WMAS technology, its future in the industry, and its regulatory framework for professional audio applications.

Outboard DSP: miniDSP Flex

May 21, 2025 by Vance Dickason

Outboard DSP: miniDSP Flex

The fourth in a series of product reviews of outboard DSP hardware, this article explores the miniDSP Flex digital signal processing (DSP) unit. The Flex is a two channels in/four channels out, Sharc-based audio processor that offers a more cost-effective model than the previously featured miniDSP processors in the series, with a retail price of $570 for the TRS balanced IO model. Besides the competitive price, the review confirms how the miniDSP Flex manages to measure and impress.

Fresh From the Bench: mh acoustics Eigenmike em64, Sixth-Order Ambisonics Microphone and Software Suite

May 14, 2025 by Philipp Paul Klose

Fresh From the Bench: mh acoustics Eigenmike em64, Sixth-Order Ambisonics Microphone and Software Suite

A unique insight into the future of microphone technology, this article reviews the Eigenmike em64, a sixth-order Ambisonics microphone with Dante connectivity, extended with a comprehensive recording and decoding software suite. Updating its previous Eigenmike em32 model, the company introduced a state-of-the-art higher order Ambisonics capture tool to the market. The patented design combines microphone programmable gain preamplifiers, 24-bit A/D conversion and microphone calibration, all integrated.

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

May 1, 2025 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.

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

April 23, 2025 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.

Voice Coil February 2025. From DSP to Cones and Domes.

January 28, 2025 by audioXpress Staff

Voice Coil February 2025. From DSP to Cones and Domes.

This issue includes a new product review in Vance Dickason’s Outboard DSP series, exploring the miniDSP Flex audio processor. And Dario Cinanni explains how to Enhance Loudspeaker Efficiency and Bl(x) Symmetry with the Virtual Voice Coil software from SpeakerLAB. As scheduled, Mike Klasco and Nora Wong compiled the 2025 Cone and Dome Directory. For this month’s Test Bench, Vance Dickason characterizes the Faital Pro 5PR120 5” Pro Midrange Driver.

Find All the Cutting-Edge Audio Knowledge in audioXpress February 2025

January 13, 2025 by audioXpress Staff

Find All the Cutting-Edge Audio Knowledge in audioXpress February 2025

Read the Market Update on MEMS microphones, Shure’s valuable perspective about Wireless Multichannel Audio Systems (WMAS) technology, and a review of the extraordinary Eigenmike em64 Ambisonics microphone. Brent Butterworth reviews the new Sony MDR-M1 headphones, and Alex Bonnet and Eric Benhaim (Orosound) explain how to leverage ANC in open-ear designs. Brian Lowe (Belleson) shares his Top Amp design for phono preamps, Douglas Self reveals more op-amp distortion tests, and Richard Honeycutt revisits the legendary Dynaco ST-70 and ST-70 II tube power amps.