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Industry & Product News
Western Electric to Debut 777 rAMT Midrange Driver at High End Munich 2022
After successfully rebooting tube production in the US with the relaunch of the 300B, and introducing the stunning new 91E Integrated Amplifier, Western Electric has been busy in other areas. Charles Whitener, the entrepreneur and current president and CEO is determined to take Western Electric to a leading market position in home audio and is also investing in new speaker technologies. The first results will be visible at High End Munich 2022 with the presentation of the new 777 rAMT Midrange Driver. Read More
AudioControl Embraces GaN Performance for New 70-Volt Amplifier Series
AudioControl is determined to expand its nearly 5-decades long legacy of best-in-class audio solutions by introducing a groundbreaking audio amplifier platform leveraging GaN (Gallium Nitride) semiconductors from GaN Systems. AudioControl engineers say they have created a circuit that establishes a new bar for power and sound quality, now available in the CM Series four-channel, three-channel, and two-channel 70V Dual-Mode amplifiers. Read More
Home Audio Industry Reconvenes at 2022 High End Show in Munich
The prestigious High End Munich show finally returns to the MOC exhibition center - and pretty much the entire city of Munich, as the consumer, hi-fi, and high-end audio companies return to in-person events. Promoted by the local High End Society and reputed as the best trade show in the world for consumer high-quality audio products, the 2022 High End Show (May 19-22) has now expanded with the new International Parts & Supply (IPS) B2B segment and more valuable initiatives. Read More
DeusO Announces AES70 Explorer Software Application
DeusO GmbH has released AES70 Explorer, a free Windows/macOS software to support hardware engineers developing or integrating AES70 into Pro Audio devices. AES70 is an open control and monitoring standard for professional audio and video network devices, promoted by the OCA Alliance industry consortium, AES70 Explorer is designed to connect, expose, and control parameters in OCA objects. The software provides a UI builder for fast setup of engineering interfaces and can simultaneously test multiple devices using an array of Pro Audio control widgets. Read More
Listen Releases SoundCheck 20 Audio Test Software Upgrade
The much anticipated SoundCheck 20 audio test software update has been released, and Listen, Inc. is offering incentives to help users upgrade to the latest version.​​​​​ The motivations to upgrade are many, starting with the fact that SoundCheck 20 introduces Listen’s state-of-the-art perceptual distortion algorithm for end-of-line testing – Enhanced Perceptual Rub & Buzz. SoundCheck 20 also includes a host of new features for multichannel and communications testing. Read More
Pro-Ject Announces New Accessible E1 Line of Turntables
Pro-Ject USA announced the new E1 line of turntables, designed and produced in Europe. The new collection aims to introduce a new audience of music lovers to the world of vinyl by offering quality technology at an accessible price point, starting at $350. The E Line consists of three models, the E1 ($349 USD), the E1 Phono SB ($399 USD), and the E1 BT ($499 USD), available in high gloss black, satin white, or satin walnut finishes. Read More
JH Audio Debuts Flagship In-Ear Monitors Featuring New Knowles Balanced Armature Supertweeter
Knowles Corp. announced a new partnership with Jerry Harvey Audio as it debuts Sharona, an over-the-top, flagship 16-driver in-ear monitor (IEM) design using a four-way crossover that is intended to serve the ultimate sound quality to performing musicians and sound engineers alike. The new JH Audio IEMs are the first product to incorporate the superior treble output capability of the new Knowles RAU-34851-B148 balanced armature Supertweeter. Read More
ALTI Expo 2022 and the Return of the ALMA Awards, June 5–6
ALTI Expo 2022, the conference and showcase promoted by the Audio & Loudspeaker Technologies International (ALTI) Association is right around the corner, set for June 5-6 at the South Point Hotel and Casino in Las Vegas, NV. As planned, it will take place a few days before the InfoComm 2022 show, which takes place June 8-10 at the Las Vegas Convention Center - and offers an education schedule starting June 4—10. Don't miss the great technical presentations and quality networking with professionals in the loudspeaker industry and the related signal chain. The South Point Hotel offers great deals for those attending. Read More
THX Licenses VisiSonics’ 3D Immersive Audio Tools and Personalization Solutions
THX has licensed certain 3D audio and personalization technologies from VisiSonics, the 3D spatial audio and acoustic environment optimization technology company, and is incorporating them into its products. VisiSonics technologies will be utilized in THX Spatial Audio tools for game developers and music producers, and advance THX audio personalization for headset manufacturers. VisiSonics technology is also expected to be a part of anticipated THX offerings in the emerging market of hearable technology. Read More
Guest Editorial
Oliver Masciarotte
AXPONA 2022 First Impressions
Back to Listening in Schaumburg
It was with great anticipation that I entered the AXPONA venue in the Chicago, IL, suburbs for the first time in three years. Would it be as exciting and illuminating as the Before Times? I needn’t have worried. Everyone, whether dealer, manufacturer, or attendee, was as stoked as I to be at an in-person gathering. After all, the whole point of a hi-fi show is to hear the differences that each system brings. Zoom simply cannot convey that nuance.
GaNFETs
At AXPONA 2019, there was one. Now there are at least four and I predict that, no surprise, the number of manufacturers using Gallium Nitride field-effect transistor (GaNFET) output devices will grow rapidly over time. At this year’s show, both hollow-state stalwart Atma-Sphere and digital dynamo Mytek were demoing GaN-based prototype amplifiers to very good effect. As I’ll mention again in my full show coverage, the Mytek room’s combination of an Empire streamer feeding pre-production but still attractive GaN FET Empire Monoblocks via Transparent Audio cabling coaxed the best sound I’ve heard from the, to me, rather uninviting and quite spendy Wilson Sasha speakers.

Michal Jurewicz, Mytek’s founder and CTO, began strategic work on Class D amplifiers several years ago when they made their first Brooklyn AMP, followed by the improved Brooklyn AMP+. Jurewicz says that Class D circuits are similar in both architecture and design challenges to their core expertise of DACs and ADCs. Their new generation of GaNFET-based amplifier is about 20 times faster than the fastest silicon MOSFET transistors used in prior Class D designs. “In Class D amp topology, an ideal output of perfectly square waves will result in 0% distortion with a transfer characteristic that is a straight line, unlike elliptical curves for Class A/B. The main problem with Class D to date was that slow switching MOSFETs corrupted the square waveform, (which) directly translates into ugly distortion, especially for low level signals where there is an effect similar to 16-bit truncation resulting in a disappearing or flat sound stage. All the low resolution signals, rather than being buried in distortion, are now audible, resulting in a detailed and realistic soundstage with a hint of ‘tube sound’ because of the straight line characteristic of the amp."
Atma-Sphere’s new unassuming and high-performance Class D.
Along with that reduced distortion, which we’ll hear about again in a moment, comes tightly controlled bass thanks to “...the massive current drive of 60+ Amps" that a GaNFET can easily deliver. Yet another benefit is very high efficiency, up to 95%. So, no heatsinks. That was the primary incentive for invention of GaNFETs; to be used for electric power conversion (electric automobiles, wind, and solar) where they contribute to significant reduction of heat and the overall size of the circuit. The diminutive $9995 Empire amps, half-rack wide and about 2U tall, make 1000W into 4Ω and half that into 8. The modulator runs at a brisk 768kHz, with "...very little (feedback), just to get the loop running." For his design, Jurewicz contends that, "Feedback is not essential for distortion reduction."

A closed top cover is standard, but the prototypes at the show had the optional open top, hollow-state look. Designer Jurewicz shares the view with Alberto Guerra at AGD Productions and Ralph Karsten at Atma-Sphere Music Systems that, when done right, GaNFETs have a tube-like “velvety top” and liquid midrange. For Jurewicz’s design, he wanted the option to visually reinforce the hollow-state vibe, so he borrowed Guerra’s glass approach and added the ability to alter the lighting’s hue or disable it entirely as with the logo on his DACs. In Jurewicz’s words, the ersatz tube telegraphs “the soul” of his amp.

In Ralph Karsten’s Atma-Sphere room, his new Class D monoblocks were a revelation. Expecting to hear about high costs, the constrained availability of parts and the need to address climate change directly through reduced energy use, I was instead floored to hear Karsten tell me his amps best his tube designs for fidelity. He instead cited how they combine the sweetness and musicality of tubes with the extended top and iron grip LF of Class D. “If an amp manufacturer isn’t (paying attention) to Class D, they’re going to get left behind.”

While that may be a bit extreme, there will always be a demand for Atma-Sphere’s exemplary valve offerings, Karsten does have a point. His opinion was echoed by Lars Kristian Kristensen CEO of the Danish Ansuz/Aavik/Børresen juggernaut. Kristensen was describing to me some of the rather rad thinking that went into the development of their new cable line, and worried that the high-end hi-fi manufacturing community is far too conservative. He stressed that old ways of thinking are leading to decline in the industry.
Pre-production prototypes of the Mytek Empire Class D Monoblocks, on display for the first time at AXPONA 2022.
The Atma-Sphere room ran a modest system by show standards. Analog came in starting with a $750 Hana SL cartridge and $1700 Technic SL-1200G equipped with their own custom turntable interconnect. Digital was provided by a $600 Audiolab 6000CDT transport feeding a $900 Topping D90SE. Sources were both balanced into Atma-Sphere’s venerable MP-1, the industry’s first balanced preamplifier. The MP-1’s balanced out led into the $5400/pair “Class D.” All cabling was custom Mogami Neglex. That whole rig fed both a Tang Band full-range driver in a “Plexibox” enclosure, along with an AudioKinesis Swarm with the help of Jensen LF-optimized unbalancing transformers.

The unpretentiously named Class D model is homespun. It is engineered entirely by Karsten and his team, making 100W into 8Ω. “Some people say we’ve gone over to the dark side,” Karsten admits, but the new model is “...as smooth and organic (as his tube amps), but with about two orders of magnitude lower distortion. Far more transparent.” Karsten posits that higher-order harmonics are far more audible than people think. “We made sure in this design that the high-order harmonics are NOT audible.” His listening test informed him that typical distortion contributes to a bright signature, even when the signal has been low-pass filtered.

The Class D is, of course, self-oscillating but, unlike Mytek’s, it has 37dB of feedback. During our discussions, Karsten cited work by Norm Crowhurst and later Peter Baxandall on the limits of feedback. Since his design is meant to oscillate at around 500kHz, the oscillation becomes the switching frequency. In a “normal” design, the feedback becomes less as input frequency increases due to capacitance and other effects and, at some point, the feedback switches from negative to positive and the amp starts oscillating. In his design, the feedback is consistent across the audio passband, even at higher frequencies. Hence, the distortion is constant and controlled at all times. That consistently low distortion, he contends, is what lends the transparency he finds so attractive in the new amp’s design.

I mentioned climate change earlier and the need for less wasteful gear. The GaN FET devices Atma-Sphere uses, typically used in motor control applications, are so thin and light that they heat up and cool off very quickly, so no need for a heatsink. The Class D can pump 200W into 4Ω all day without breaking a sweat. On resistance is very low, about 50mΩ, so it also has a very low output impedance. The filter choke actually defines the output impedance, but the feedback masks that and Karsten claims that the amp acts as an ideal voltage source.
The Renaissance Schaumburg atrium was a pleasant environment to stop and pause or just pass through.
The Future Is Cloudy
At AXPONA, I was struck by a parallel development—how HRA streaming has allowed exhibitors at the biggest hi-fi show to embrace streaming sources. Although there will always be all-analog rooms housing turntables with six digit price tags and five figure amplifiers, the vast majority of the demos I attended were sourced by Qobuz, my favorite HRA delivery service.

Arriving on the American scene in a big way back in February of 2019, the French content provider has taken at least one audio show by storm. David Solomon was everywhere at once, drumming up business and continuing to nudge his ward into the top position. AXPONA 2022 was the first show I have covered where I carried no CDs, no SACDs, and no flash drives. I pre-selected a handful of songs to use as my test material, and Qobuz supplied the content. There were a very few vendor holdouts that brought their own demo tracks for use with Roon, but they were by far the exception.

Some of the very best sounding rooms, including T+A elektroakustik and Mytek, were sourced by Qobuz which, to me proves that streaming is simply another extremely convenient way to deliver bits to a DAC. When designed properly, it can equal the quality that optical discs or “hard drives” provide. The blame for any shortcomings must be laid at the feet of the designer, not the streaming mechanism itself. A dirty secret; I already listen to Qobuz for both enjoyment and review analysis way more than my local storage.
The Magnesium - Almost everything that goes into a Period IEM is manufactured in-house.
Rolling Your Own
Mytek’s and Atma–Sphere’s amp projects were both internal designs, without reliance on third-party Class D modules. Another vendor, Periodic Audio, manufactures pretty much everything that goes into their new line of lovely sounding and rugged IEMs. That leads me to one last observation, brought to my attention by Periodic’s Dan Wiggins. It was something to the effect of “He who tools, rules.” By that he meant that those who bring in-house all aspects of manufacturing reap the myriad rewards. Tighter process control; the beneficial synergies between design and factory floor; an improved ability to better manage inventory and more means that, to him, outsourcing should be used more wisely and less as a cost-reducing panacea. With all the other lessons that the pandemic has taught us, that’s one truth worth repeating.

Tbc.
The Periodic Be with a Tritan copolyester body and Beryllium + PEEK diaphragm.
Development and Design
On the Edge: TinyML and Voice Recognition Technology Are Transforming Industries
By Vikrant Tomar (Fluent.ai)
Consumers increasingly expect voice-enabled devices like home assistants or wearables to operate offline and in a secure manner no matter the environment. Rising demand for portable, light footprint voice recognition devices is fueling a growth of the tiny machine learning (TinyML) field. Offering a broader, high-level discussion specifically focused on voice recognition, Vikrant Singh Tomar, the founder and Chief Technology Officer of Fluent.ai, explains the impact for embedded voice and the overall audio industry. Essential reading for audio developers working in this cutting-edge space, as a new generation of personal devices process data locally, taking the cloud and data centers out of the equation. This article was originally published in audioXpress, February 2022. Read the Full Article Now Available Here
Voice Coil Spotlight
Metamodal TPCDs — Next-Generation Speaker Diaphragms from Composite Sound
By Martin Turesson (Composite Sound)
This article is an exclusive inside account of Composite Sound's efforts for the loudspeaker industry, detailing the company's journey that led to the extensive use of TPCDs for loudspeaker applications and the company's second-generation Metamodal technology. The recently created company is a spin-off from Oxeon, the Swedish manufacturer of the TeXtreme brand of advanced carbon reinforcements now successfully used in multiple industries. Composite Sound Metamodal introduces a new engineering approach that allows designing loudspeakers tailored for an intended purpose, realizing a physical representation of a TPCD computer-simulated model that is only achievable through the company's unique proprietary production process. This article was originally published in Voice Coil, February 2022.  Read the Full Article Now Available Here
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