Explore Audio Amplifier Technology and Design in audioXpress July 2021

One of the strongest issues ever in terms of audio electronics and market insights, audioXpress July 2021 is now available. This edition includes a complete overview of Audio Amplifier Technology and Design and its many application segments. Start with a review of the NAD Electronics M33 Masters streaming amplifier, followed by a great new upgrade design for the legendary Hafler DH-220 lateral MOSFET power amplifier, and then dive into a new hybrid voltage source and current source amplifier design for loudspeakers.

We looked at the most-read articles of 2020 in audioXpress.com (which also includes selected articles from Voice Coil magazine), and we created this Top 10 list of news stories and online articles. 2020 was another record-breaking year for audioXpress.com, with visitors from all over the world returning often to read the more than 6,600 stories available. Which of the topics and stories published online in 2020 were the most popular? Here are the results!

Stuart Yaniger examines new amplifier solutions from two disrupting audio companies. Purifi Audio from Denmark, founded by Bruno Putzeys, Lars Risbo, and Peter Lyngdorf, together with a remarkable engineering team; and Orchard Audio, with a product developed from the creativity and entrepreneurship of Leonid (Leo) Ayzenshtat, in this case exploring the latest gallium nitride (GaN) semiconductor technology. This article was originally published in audioXpress, July 2020.

For those audio enthusiasts considering their options to acquire a new amplifier that uses Purifi Eigentakt amplification technology, NAD Electronics announced another high-performance, affordable and very attractive option. The C 298 is a two-channel design that is a perfect partner to high quality preamplifiers or in any application where additional channels of high end audio amplification are desired. This new NAD classic amp boasts 185 Watts per channel into 8 Ohms and can be bridged to 620W X 1 into 8 Ohms to create a huge Monoblock.

NAD Electronics unveiled another new and unique Masters Series product. The M28 is a seven-channel high performance amplifier that can serve as a powerful engine for a state-of-the-art multi-channel system for music or home theatre. And, like the recently launched M33, this reference multi-channel amplifier features Purifi’s Eigentakt (self-clocking) amplifier technology. The M28 ($4999 U.S. MSRP) is available now to order and will begin shipping in August, 2020.

Following a preview at CES 2020, the highly anticipated amplifier of the year 2020 by NAD Electronics - the first company to license Purifi Audio's amplifier technology - is now shipping! NAD M33 is the latest BluOS enabled DAC/amplifier that can serve as the heart of a reference whole-home system. In its simplest form, the M33 ($4999 U.S. MSRP) is an ultra-high-performance streaming amplifier with superb sound. And it can obviously be combined with a BluOS ecosystem of wirelessly networked music players, creating a whole-home audio system.

audioXpress July 2020 is now available, and there's a quiet revolution happening in audio amplification. Essentially it is the direct result of strong innovation in Class-D technology, with incremental improvements introduced on multiple fronts. In this month's Market Update, J. Martins details a few of the "Class-D Products Getting Smarter" and then Stuart Yaniger discusses Class-D amplifiers from two of those companies: Purifi Audio and Orchard Audio. Also, Ward Maas details his visit to Purifi Audio. Dimitri Danyuk shares his "Fully Balanced Transconductance Preamplifier" project, Roger Russell is "Hunting the Elusive Transient," and Ed Simon concludes his "Powering Your Circuits" series. And there's much more valuable content in this edition. Download or view your issue online now.

Purifi Audio, the Danish company founded by Bruno Putzeys, Lars Risbo, and Peter Lyngdorf together with a remarkable engineering team, promises Class D amplifiers with record-breaking performance (as well as speakers). Now, Bruno Putzeys made available a detailed report of his investigation on hysteresis distortion, which motivated the development of the company's products. As Putzeys describes, hysteresis in the ferromagnetic material of the amplifier output filter coil is what causes "a recognizable grainy texture in the sound."

NAD Electronics is previewing another exciting Masters Series release at CES 2020! The M33 is a BluOS enabled DAC/amplifier that will also be the brand's first product to feature Purifi Audio's new amplification technology. In its simplest form, the NAD M33 is an ultra-high-performance 200W amplifier that can serve as the heart of a reference whole-home system. For the brand, this will be its new flagship model, featuring BluOS multiroom streaming, Gorilla Glass touchscreen controls, 32-bit ESS Sabre DAC, full MQA decoding, and Dirac Room Correction.

Want to know which of the topics and stories published online in 2019 were the most popular? We looked at the most-read articles of 2019 in audioXpress.com (which also includes selected articles from Voice Coil magazine), and we created this Top 10 list of news stories and online articles. Here are the results!