Doing It Differently

Time moves quickly. We are already feeling the aftermath of 2014’s first two major industry shows. This is also a year when audioXpress is completing its transition to an expanded publication that addresses the needs of the audio engineering community—not only for those who have fun listening to music (there are plenty of magazines doing that) but mainly for those who imagine, create, and work with audio technology.

This year began with the 2014 International Consumer Electronics Show (CES) in Las Vegas, NV, introducing innovations on all fronts. It was also the largest CES in show history. While some companies introduced products based on users’ needs, it appears many consumer electronics companies still prefer to throw hundreds of new ideas at the wall to see what sticks. I guess a major electronics show like the CES is the ideal place to test those ideas, but sometimes we have to wonder why the successful companies that only introduce market-ready products don’t even need to attend the CES.

Yes, we miss seeing Apple at trade shows and we miss the inspiring clear vision of the late Steve Jobs. Apple is one those companies with products that are the perfect combination of state-of-the-art technology and innovation that are available for purchase exactly as advertised. And while the company was not in attendance, Apple’s products still dominated the 2014 International CES. It is no surprise that many great ideas and reference designs were designed to complement the iPad, the iPhone, and even the new Apple Mac Pro workstation.

IK Multimedia promoted its iRing wireless sensors to control music apps (or any other apps) using only gestures. We’ve also seen great photography peripherals for the iPhone and many new charging and home-automation solutions. There are even iOS-device-controlled robots and drones. And of course, no audio company could ignore the huge market created for wireless speakers and headphones. Many were especially designed for Apple’s mobile devices, leveraging Apple’s push for Bluetooth Smart 4.0 and AirPlay technologies. Apple also effectively revitalized the worldwide home audio market.

Wireless speakers, headphones, soundbars, integrated A/V receivers and audio systems are experiencing impressive growth rates, according to recently published market reports. Bluetooth products, in particular, continue to bolster the wireless speaker market, offering the convenience of portability, while multi-room audio based on Wi-Fi is also on the rise. Among the 20,000-some products introduced at the 2014 International CES, there were a significant number of new headphones and earphones.

After every CES, we should also acknowledge those sparks of inspiration from obscure companies and the truly exciting technology announcements. For example, cars connected to mobile networks—actually talking and seamlessly interfacing with our mobile devices.

It’s always difficult to understand why, but clearly, in the middle of all the Internet-connected toothbrushes and forks, speech-recognition watches, and curved television screens, some innovations make complete sense and leave us asking ourselves “why did it take so long?”

João Martins
Editor-in-Chief

Q&A: Dan Dugan – Audio Engineer, Inventor, and Nature Sounds Recordist

Dan Dugan

Dan Dugan was the first person in regional theater to be called a “sound designer.” He also developed the first effective automatic microphone mixer—the automixer. He is shown here with his museum rack of Dugan automatic mixers.

SHANNON BECKER: When and how did you first become interested in audio electronics?

DAN DUGAN: As a child! I was most interested in theater lighting. I was raised in San Diego, CA, and when my parents took me to the Old Globe Theatre or the summer musicals in the Ford Bowl, I always wanted to go backstage to see the light board. In grade school, I operated the projectors, the tape recorders (Wollensak and Revere), and the sound systems (Bogen).

SHANNON: When did you attempt your first audio project?

DAN: In grade school, I remember making up a program on tape. Something historical, but I can’t remember what it was about.

SHANNON: Describe some of the jobs you had prior to inventing the automatic microphone mixer.

DAN: After doing all the lighting for four years at the University of San Francisco (USF) College Players and for concerts in the USF Gym, I did sound for the Globe Theatre in 1964 and lighting and sound in 1965, and lighting for the first production of the San Diego Opera in 1965. In 1967, I switched to doing theater sound, working for the San Diego National Shakespeare Festival and the American Conservatory Theatre in San Francisco.
[The title “Sound Designer” was created in 1968 to describe what Dan was doing. He provided sound services for many seasons of the Mondavi Jazz Festival, and engineered several independent record albums, including Kate Wolf’s first two albums which are still in print, now as CDs].

1978 Globe studio

Dugan was raised in San Diego, CA, where his parents took him to the Old Globe Theatre. Here he is pictured editing sound in a dressing room at the Old Globe Theatre in 1978.

SHANNON: Describe what the term “sound designer” means to you.

DAN: In theaters a “sound designer”  supervises the sound from the microphones to the audience’s ears. In motion picture production there are two meanings. The first is the same as in theater, also called supervising sound editor, and the second usage is for a person who creates novel sounds like monsters.

 

SHANNON: How did you come up with the idea for the automatic microphone mixer?

DAN: In 1968, I did sound design for the resident companies of Hair in Chicago, Las Vegas, and Toronto. There were 36 microphones and one operator working rotary-knob mixers in a rack. I thought there had to be a way to help. I experimented for about six years and hit on a solution.

SHANNON: Tell us about some of your other inventions. Which is the most popular? Are any currently in production?

Model Dugan MY16

One of Dugan’s most popular products is the Dugan-MY16, a 16-channel automatic mixing controller that plugs into a slot on Yamaha consoles. The controller enables sound engineers to manage multiple live microphones without continually riding individual faders. The Dugan-MY16 automatically detects the active microphones and makes fast, transparent cross-fades without the distracting sonic artifacts common to noise gates. It tracks unscripted dialogue and maintains consistent system gain for up to 16 open microphones.

DAN: The Dugan Speech System is my most popular invention. It is 40 years old and still finding new applications. There’s also the Dugan Music System, a distant second, and Dugan Gain Limiting. In limited use but with more coming soon is the Dugan Automatic Level Control. Unrealized as of yet but in the wings are Dugan Foldback Limiting and a Dugan Speech Equalizer.

 

SHANNON: Tell us about “A New Music and Sound Effects System for Theatrical Products,” which is the sound design paper you presented to the Audio Engineering Society (AES) at its 37th Convention. Did you realize its future implications when you wrote it?

DAN: In the paper, I described a system in which the signals from three stereo tape players were routed to 10 loudspeaker zones in the theater. Audio mixing boards generally combine a large number of inputs to a small number of outputs—that’s mixing. For playback of theater cues, the opposite was desired, routing a small number of channels over a large number of speakers. As there was nothing like that available, I designed and built a system from scratch. It was the first multi-scene preset board for theatrical cues playback, sending three stereo tape decks to ten speaker channels. And I described my work in that paper. Subsequently, Charles Richmond, of Richmond Sound Design, designed products developing the concept further.

SHANNON: Your patented equipment has been used in thousands of places, including the courtroom where Saddam Hussein’s trial took place and on the David Letterman Show. Can you share other locations where your equipment may be found?

DAN: My equipment is used in corporate meetings everywhere, from ESPN sports to PAC-12 sports to US Presidential debates and on several television set locations including Washington Week and PBS News Hour.

Model E Series

The Dugan Model E-2 automatic mixing controller is used with multiple live microphones. This updated unit replaces the Dugan Model D-2 as the company’s top-of-the-line automatic mixing controller with analog I/O and is useful for users who are working in tight spaces or who need portability in their analog Dugan system.

SHANNON: Your San Francisco, CA-based company Dan Dugan Sound Design (www.dandugan.com) produces automixing solutions. Are you currently developing any new  products?

DAN: We recently added the Model E-2 to complete the E-series (E-1A, E-2, E-3). We are also just about to ship the Dugan-VN16, an option board for Avid live sound mixers.
Next out for our company will be a new physical control panel for Dugan automixers. It can be used when you are working under pressure and real knobs and buttons are better than mouse clicks.

 

SHANNON: To what do your attribute your company’s continuing success?

DAN: Persistence, good luck.

SHANNON: You are known for your use of natural sound recordings. When and why did you first begin capturing the sounds of nature?

DAN: I was the Northern California service shop for Nagra Audio. Around 1987 or 1988 one of the founders of the Nature Sounds Society worked at the Oakland Museum and he brought a Nagra recorder in for service. He mentioned that every summer they had a camp in the Sierras and invited me to come. I started mentoring with the Nature Sounds Society, teaching people how to get the best sound from their equipment. I started recording for myself at the end of 2001 when I took a borrowed MiniDisc recorder for a trip to New Zealand and I recorded an album’s worth of good stuff.

SHANNON: Where do you conduct your outdoor recordings?

 

Dan Dugan recording

Dugan records ice falls at Upper Yosemite Falls in Yosemite Falls National Park, Mariposa, CA.

DAN: One of my favorite locations is Muir Woods [National Monument in Mill Valley, CA] because it’s so accessible. I also enjoy recording in Mariposa Grove in Yosemite National Park because it is sublime and at Joshua Tree National Park [in southeastern California].

SHANNON: What do you see as some of the greatest audio innovations of your time?

DAN: “Of my time” meaning in my career? I think there are several including solid-state electronics, integrated circuits, electret condenser microphones, and digital audio.

SHANNON: Would you recommend any promising technologies to audioXpress readers?

DAN: Audio over Ethernet.

Q&A: OrigAudio Founders Jason Lucash and Mike Szymczak

OrigAudio founders

Jason Lucash (left) and Mike Szymczak (right) constantly traveled early in their careers and wanted an easy way to listen to their music on the road. During their travels, they came up with the idea for OrigAudio.

SHANNON BECKER: Describe your background (e.g., where you grew up and your education).

JASON LUCASH: I’ve always been an “entrepreneur at heart.” I’ve always had a knack for being a self-starter. I started my own candy stand when I was in the second grade. My family would buy candy in bulk from stores such as Vons and Safeway, and then I would race home from school to put my candy stand out in the path of students as soon as school was over. My buddies and I would hang out, eat candy, and sell it, making about $30 dollars a day.

MIKE SZYMCZAK: I’ve always had a wondering mind. I liked to tinker and be different from the crowd. From a young age my father, Jimbo, would bring me to the science store to explore and learn how things worked scientifically and mechanically. He also encouraged me to try and experience as much in my life and career as possible. I took this advice to heart. I held more than 20 jobs, all before I turned  25, and I visited more than 20 countries and 48/50 states. Always one for a new adventure and a new challenge, I decided to start my own business. This entrepreneurial spirit, a passion for music, and zest for travel helped to forge OrigAudio.

Jason and Mike recognized a need for an eco-friendly, portable solution for listening to music while on the go. Inspired by a Chinese take-out box—foldable, easily compactable, and recyclable—the “origami of audio” was born.

Jason and Mike recognized a need for an eco-friendly, portable solution for listening to music while on the go. Inspired by a Chinese take-out box—foldable, easily compactable, and recyclable—the “origami of audio” was born.

SHANNON: What sparked your interest in audio?

JASON/MIKE: Both of us are marketing guys who recognized the need for a light, ultra-portable speaker.

SHANNON: How did the two of you meet? And what made you decide to go into business together?

JASON/MIKE: We met on the job, which required a lot of travel. This is how we came up with our “million dollar idea” for cool, portable speakers.

SHANNON: Tell us about OrigAudio (www.origaudio.com). Where did you get the idea for the company?

JASON: Our first product, the Fold and Play speakers, uses the principles of origami to come flat and fold up into a speaker. This inspired the name OrigAudio—the Origami of Audio.

MIKE: It was out of need from our travel heavy jobs. We just wanted to create a better way that saved space, didn’t require batteries, and was ECO Friendly.

Fold and Play 2

The Fold and Play speakers are the product that started it all. These speakers are made from 70% post-consumer recycled material, require no external power, and fold and unfold like origami.

SHANNON: Tell us more about the Fold and Play portable paper speaker. What was the inspiration behind it?

JASON: Tired of lugging bulky audio players around on business trips while working for JanSport, Mike and I started futzing with the idea of putting speakers into Chinese-food takeout boxes. The box starts flat, and whenever you want to use it, you pop it up. Our idea sounded good. The product? Not so much. We moved on to putting a very old idea—origami—to work. In 2009, with $10,000 in seed money from my mom, we launched OrigAudio (origami + audio) with one product: speakers, which are made entirely from recycled materials that start out flat and fold together. The Chinese takeout box concept inspired us, but origami is what powered us.

MIKE: We were still working our “day jobs” and selling 15 pairs of speakers a day through our website when the US Marines placed a whopping order for 50,000 (launching OrigAudio’s corporate gift division). Shortly after, Time magazine waved its magic “best” wand. [OrigAudio was named to Time magazine’s “50 Best Inventions of 2009” list and appeared on ABC’s hit start-up business show, Shark Tank.] With the holidays coming on fast, the company quickly sold out of its 25,000-unit stock. That’s when we gave our two-week notice to JanSport.

SHANNON: Can you share some of the challenges involved with the designs?

JASON: The first version of our Fold and Play speakers were kind of a huge flop. I couldn’t even get my mother to take them seriously. They were literally just a Chinese take-out box with a speaker attached and could barely even stand on their own. So we went back to the drawing board, ditched the take-out box, and adopted the principles of origami to create our first successful product.

Rock-It Cup

The Rock-It 3.0 portable vibration speaker system takes music from your device and turns it into vibration sequences. It sends those vibrations through the Rock-It pod which sticks to any object and turns that object into a speaker!

SHANNON: What other products have you developed?

JASON: OrigAudio’s top-selling product is the Rock-It, which makes a speaker out of pretty much any hollow object you stick it to. It’s another example of the old-made-new strategy. The really cool technology had been around for 60 years, but we always saw these big applications. So we thought, “This thing would be sweet if you could make it portable.”

MIKE: We also came out with the world’s first ever fully customizable speakers. These products give consumers the opportunity design and personalize their very own speakers. More images of the Doodle, Cubicool, Epishock, and Headphones are available on our website.

SHANNON: To what do you attribute your company’s continuing success?

JASON: I think people love being able to customize their gear. I personally don’t want headphones that only have a brand name on the side of them. I want headphones that reflect my personal taste. For instance, I love robots and have them all around my office. Therefore, I want headphones that have robots on them, too. I prefer to buy products that are an extension of my personal taste and preferences.

MIKE: We don’t take ourselves seriously, but we do take our business seriously. People like working with us and they love our unique products.

SHANNON: What’s next for your company?

JASON/MIKE: On demand customized products are not only the future of our company, but the future of business. Not only is customization great for our customers, it’s also incredibly effective for businesses. Twenty years from now, retailers won’t need to stock physical products in distribution centers (with the exception of food and canned goods). A customer will be able to order a watch from Amazon and have it made exactly how they want it to look and feel on demand. Even though customization has been around for a long time, more and more business owners are focusing their businesses on this fast-growing trend.

Epishock

New to the OrigAudio family is Epishock, a device that turns any flat surface into a bass pumping loud speaker. Place Epishock on a hard surface (e.g., a desk or table) and witness vibration technology at its best.

SHANNON: What do you see as some of the greatest audio innovations of your time?

JASON: Noise-cancelling technology. It completely changes your listening experience.

MIKE: The iPod/MP3 player. The ability to transport an entire library and hundreds of CDs/records/cassettes in the palm of your hand is unreal.

SHANNON: Do you have any advice for our audioXpress readers who may want to build their own sound systems?

JASON: You should always be a step ahead, especially in technology. In technology, you should probably be two steps ahead because the technology is always changing.

MIKE: Explore the unexplored…meaning basically create something entirely new do not reinvent the old.

Industry Watch: January 2014

2013 CEA Technology Winners

Charlie Hughes

Photo 1: Charlie Hughes earned the 2013 Consumer Electronics
Association’s (CEA) Technology & Standards Award for his work on CEA-2034.

The Consumer Electronics Association (CEA) recently announced the winners of the sixth annual Technology & Standards Awards. Nominees were judged on their commitment to excellence as evidenced by the extent and consistency of their overall ongoing contributions to the CEA’s Technology & Standards program.

“This year’s award recipients have demonstrated industry leadership through active participation in the CEA’s Technology & Standards program both over the long term and with recent projects,” according to Brian Markwalter, the CEA’s senior vice president for research and standards. “All of our honorees have dedicated countless hours to creating standards that launch new product categories and make existing products easier to use.”

Charlie Hughes received one of this year’s awards for standards pertaining to loudspeaker development (see Photo 1). Hughes is president of Excelsior Audio Design & Services (www.excelsior-audio.com) and the co-chairman of CEA’s Sound Measurement Working Group. He received this prestigious award for spearheading the publication of CEA-2034, Standard Method of Measurement for In-Home Loudspeakers. Hughes is also a contributing Voice Coil author. Congratulations Charlie!

 


2014 CES Best of Innovations Awardees

The CEA also announced its list of 2014 International Consumer Economic Show (CES) Best of Innovations Design and Engineering award honorees. The CES Innovations Awards honor outstanding design and engineering advancements across 28 consumer electronics product categories, including two new categories this year: 3-D Printing and Additive Manufacturing and Wearable Technologies.

The Best of Innovations designation is awarded to products with the highest judges’ scores and will be honored during the 2014 International CES, January 7–10, 2014, in Las Vegas, NV. The award winners will be featured in the Innovations Design and Engineering Awards Showcase in the Venetian Hotel. Award winners with products related to the loudspeaker industry include:

  • Headphones: Plantronics, the BackBeat Go 2 + Charging Case
  • High-Performance Home Audio: Bang & Olufsen, BeoLab 18
  • Home Theater Speakers: Philips Consumer Lifestyle, Philips Fidelio E5 Wireless Surround Cinema Speakers

 

 


HTSA 2013 Awards

The Home Technology Specialists of America (HTSA) presented its 2013 HTSA Vendor Awards to those who have demonstrated commitment to member growth through the development of cutting-edge products and technologies, exemplary business practices, and unyielding service and support for HTSA members. Each year the HTSA Vendor Awards go to industry professionals who have had an overwhelming impact on the success and business growth of HTSA members.

For 2013, HTSA announced the return of its Lifetime Achievement Award, one of its most coveted honors. Sandy Gross, founder and president of GoldenEar Technology, received the 2013 award. Gross’s previous company was Definitive Technology.

Other loudspeaker companies that received awards include:

  • Technology Innovation: Lenbrook Industries, the BlueSound line of wireless loudspeakers
  • Best Audio Product: Paradigm Electronics, Soundtrack home theater system

 

 


Harman Opens First US Store

HARMAN International opened its first US store on November 21, 2013, to demonstrate the company’s home, car, and pro audio products and to sell select home audio gear to consumers. The two-level, 8,500-ft2 store on Madison Avenue in Manhattan, NY, also serves as a key showroom and experience center for the company’s channel and technology partners. It will also serve as a space for its automotive OEM customers to receive a full-brand experience. Harman also plans to use the venue to host music performances and DJ sets and offer seminars to educate consumers. HARMAN will leverage its “brand ambassadors” and celebrity friends to help bring unique and memorable events to the store for Manhattan consumers.

This new HARMAN store is only the world’s second.  The first HARMAN store opened in Shanghai in 2010. A third showroom is set to open in Moscow in 2014. HARMAN has tentative plans for future stores in Los Angeles, CA, or Detroit, MI, to be close to its entertainment and auto partners.

The Manhattan store features home-theater and two-channel audio rooms, which the company’s luxury-audio dealers and channel partners can use to demonstrate equipment. The store also contains a professional DJ mixing board and interactive kiosk-style displays customers can use to learn about the company’s OEM car audio and infotainment technologies.

Multiple interactive experience areas include an interactive table display and headphone rack so shoppers can test Harman headphones by listening to provided music or by plugging in their own music players. A soundproof chamber enables customers to compare their existing headphones or select products from competing brands with HARMAN products.

The stage area features HARMAN’s professional concert and music studio equipment and will host musical performances and special events. Customers can experience large-venue premium sound in a store environment.

The store sells products for home audio enthusiasts and audiophiles. However, it does not sell products for professional sound engineers or musicians. Pro products (e.g., studio and stage microphones, headphones, and musician accessories) will occasionally be showcased, but the store won’t be a full-line showroom for pro gear.

The full line of Harman Kardon, JBL, AKG, and Infinity products is available for sale. High-performance products from the Revel and Mark Levinson brands are also displayed, but the store refers consumers to those brands’ retailers for sales. The store also offers shoppers exclusive products available only through the Madison Avenue location.

 


Bang & Olufsen Launches Industry’s First WiSA-Certified Wireless Speakers

Bang & Olufsen (B&O) has launched the loudspeaker industry’s first wireless speakers that were certified by the Wireless Speaker and Audio (WiSA) Association. Additional companies are expected to launch their first WiSA-certified products at the 2014 International CES in January. WiSA technology certification includes the delivery of interference-free, wired-quality wireless audio in the 5.2–5.8 GHz U-NII band to stereo and home-theater speakers within a room up to 29.5’ × 29.5’.

B&O’s three active WiSA-certified speakers include the compact two-way aluminum BeoLab 17 ($3,990 per pair), the 12-sided BeoLab 19 subwoofer ($3,395 per pair), and the BeoLab 18 ($6,590 per pair). The BeoLab 18 speaker features a narrow, cylindrical extruded-aluminum enclosure with a spike-shaped pedestal that appears to balance the speaker on a flat, square base. This speaker can also be wall mounted. (The BeoLab 18 is actually an update of the BeoLab 8000 speaker’s iconic design, which features a tall narrow floor-standing speaker with a spike-type pedestal resting on a flat base. It was first introduced in 1992.)

In addition to the new style base, the BeoLab 18 also adds a top-mounted acoustic lens tweeter, which delivers 180° high-frequency sound to widen the stereo sweet spot. The speaker also has a front grille consisting of narrow horizontal slats arrayed in a way that maintains the speaker’s cylindrical shape. The composite-material slats are available in black or white, and an optional natural-color solid-oak grille is available ($1,350 per pair).

The BeoLab18 delivers up to 7.1 channels of 24-bit/96-kHz uncompressed audio. Using WiSA technology to eliminate cable clutter, it enables a more flexible speaker placement and overcomes sound-quality interference, latency, and cost challenges associated with other wireless technologies designed for multichannel home theaters. B&O’s implementation delivers 24-bit, 48-kHz audio over wireless and it is less prone to interference with the lower throughputs. The company maintains the sound quality is better than CD. Other B&O news includes its recent expansion of the “Play” sub brand into 32 Magnolia Design Centers inside Best Buy stores.

From Broadcast to Home Recording to Digital Networks—Where the New audioXpress is Going

AXCover_122013Dec_120pxFor readers seeing this “second” issue of audioXpress since we introduced our new format and layout last month, I feel I should explain the concept a little more. Our target deadline for this relaunch was decided some time ago and I couldn’t think of a better place to introduce our “new” magazine than the AES convention in New York City!

I can summarize our concept in a few words: more (of what our readers expect), electronics (our roots), and audio innovation (our focus).

We are proud of our heritage as Audio Amateur, Audio Electronics, Glass Audio, and Speaker Builder magazines. Those titles were born in a time when amateur radio was still developing hand-in-hand with electronics and radio technology. And that is precisely why audioXpress is a part of the electronics publication portfolio of Elektor International Media (EIM).

But you may be wondering about audioXpress’s evolution and what to expect in the future.

It’s important to clarify that we will not continue to be a “home electronics” or consumer application-focused publication. We believe we should share the most interesting audio stories in the industry, independent of their application areas—consumer or professional, music or broadcast oriented. Hence, the innovation focus.

The most important consumer technologies often start with those developed for professionals. So, we will follow audio electronics innovations, together with the all-important disciplines of electroacoustics (and, needless to say, software, digital audio, networking protocols, and audio synthesis).

We believe that a publication such as audioXpress cannot focus only on the “home approach,” which still appeals to many enthusiasts and hobbyists. Some of us clearly remember the 1960s, when live concerts used “consumer” amps and speakers, before there were guitar amps and large speakers. At Woodstock, there were McIntosh amps (now a purely home audio brand) and the PAs were early versions of the JBL speakers (today both a pro and a consumer brand). Five years later, all the big “pro audio” brands in live sound, such as Electro-Voice and JBL, dominated that market (in the US at least). During this time, things were different in the recording studios. There, technology was first “borrowed” from radio and TV broadcasting. This is long before we had “home studios” using computers. And where exactly did that come from?

In the era of the Internet, blogs, and social networks, many magazines have disappeared. But we know a magazine can flourish. In addition to its content and its readers, a magazine must also have a purpose. It must provide a sense of community. More importantly, it needs to offer readers content they can’t find elsewhere. It does not matter if our readers are professionals, students, or enthusiasts. Our common interest unites us, whatever the platform: print, online, Facebook, Twitter, e-mail newsletters, or mobile apps.

We want to build a better audioXpress with more content, representing the common interests of the audio community while also reflecting the industry.

João Martins
Editor-in-Chief

Expanding horizons. Expanding a common passion.

AXCover_112013Nov_120xWelcome to a new audioXpress.

Having followed the audio market and visited the world’s major trade shows for the last 20 years or more, I gained a broad perspective about how exciting and innovative the audio industry is. In particular, I recall the enlightening perspective you can receive from any Audio Engineering Society (AES) convention. The convention provides a place where industry veterans can share their experiences in engineering and communications. We chose to unveil the redesign of audioXpress at the 135th AES Convention.

In the early 1990s, I was fortunate enough to be responsible for a licensed electronics magazine. I quickly learned that the audience of such practical and project-oriented publications was a combination of students, enthusiasts, and industry professionals. They all share a passion for that field, are involved in many different areas, and use their spare time to pursue electronics-related hobbies—the most popular of which is audio electronics.

Since then, I have started several publications addressing the informational needs of professionals in the broadcasting, professional audio, and installation/systems integration markets. I also learned how the evolution of technology from analog to digital and the convergence with IT platforms and IP infrastructure was changing the market landscape at an exponential pace.

During this time, Edward T. Dell, Jr. (1923–2013) was devoting his life to people with a passion for audio electronics and creating magazines including Audio Amateur (rebranded as Audio Electronics in 1996), Glass Audio, Speaker Builder, and later, in 2000, audioXpress. In 2011, Ed Dell sold his company to Elektor International Media (EIM) and retired.

Much in the same spirit of the original Audio Amateur—and with the support of a worldwide organization deeply involved in the electronics industry—we believe that audioXpress will blossom into a fascinating publication that follows the latest audio innovation trends, independent of the application field, and shares a common audience of engineers, consultants, and enthusiasts in the electronics and audio fields, most of whom are involved in R&D.

Although it was deeply rooted in the US, audioXpress—together with its sister publications Voice Coil and the Loudspeaker Industry Sourcebook—reached professionals around the world (e.g., Europe, China, India, and Brazil). It has gained more of a global presence since its acquisition by EIM, which also publishes some of the best technical books in the electronics industry.

I am really excited to bring the “new” audioXpress to a wider global audience, knowing that we can build on the tradition of the original publication and its diversified audience. We are working to create a magazine you will enjoy and anticipate reading every month.

João Martins
Editor-in-Chief

Q&A: Meir Mordachai – Morel Founder Finds Inspiration in Innovation

Meir and Oren Mordechai

Meir and Oren Mordechai

Meir Mordechai attributes the company’s success to its revolutionary designs

SHANNON BECKER: What sparked your initial interest in audio?

MEIR MORDECHAI: Music has always been a big part of my life. The love of music and my curiosity as a child to know how musical instruments play and produce different sounds led me to explore the audio field and experiment with electronics and speakers.

I’m still as passionate today about music as I was then. I regularly attend concerts and live performances to make sure that my ears are “tuned” to what musical instruments sound like, unedited, in their natural state, if you will.

SHANNON: Describe your first personal loudspeaker project. Why did you build it? Is it still in use?

MEIR: I was relatively young when I began my research and building projects. It was at the age of 11 when I tried to improve a speaker by changing its cone for another that I put together from wood veneer.

In my generation, information or electronic products were not readily available as they are today. The lack of access to valuable resources was possibly a key reason that motivated me and many others to build and innovate.

SHANNON: Your company, Morel (www.morelhifi.com), headquartered in Israel, has introduced major technological and design innovations that redefined the state-of-the-art loudspeaker technology. Can you discuss some of them?

MEIR: The desire to innovate has always driven me forward. I realized a long time ago that replicating a product would not necessarily generate business and definitely wouldn’t differentiate me from the competition. The principles of investing significant resources in new product development and in innovating and designing new ways to build speakers has been the core value behind Morel to this day and contributes greatly to our success.

There are several key technologies that were developed over the years that became the platform for our products. Our large external voice coils (EVCs) are one of the signature elements in our speakers. It turned traditional speaker design inside out. The idea was to place the magnetic drive system within the voice coil, eliminating stray magnetic flux by effectively directing all the magnetic energy to the voice coil. The result is an ultra efficient and powerful design that is highly compact with efficient heat dissipation and reduced cone breakup for lower distortion.

Because our magnet systems are placed within the large-diameter voice coils, we always had to invent new ways to achieve more magnetic energy from small magnets. Developing the double and hybrid magnet systems has enabled us to continue to enjoy the great acoustic benefits of the large-diameter voice coils.

There are many more technologies that were developed and employed in our products over the years. We continue to refine these technologies with newly developed materials that become available to us. At the same time, we keep improving the production process to increase consistency and efficacy. We never cease to research and find new ways to improve the sound reproduction; it’s a never-ending journey.

SHANNON: Tell us about Morel’s very first product. How did it come about and is it still being sold today?

MEIR: The first Morel-branded product I made was a 9” mid-bass driver, which employed a 3” coil with a paper composite cone and a single ferrite magnet motor system. Later on the development of the double-magnet system replaced the single-magnet system, immensely improving the product performance. The earlier version of the 9” driver became the foundation for several products that employ some of the original attributes of the design to this day.

SHANNON: Morel has been in business for 38 years. To what do you attribute your success?

MEIR: It can be attributed to many decisions made over the course of 38 years, but most importantly the core values I mentioned earlier, that I adopted early on, and the people who make up this company, are at the heart of our success.

I have always insisted on total design and manufacturing control. It enabled us to have the flexibility in speaker design and the ability to react quickly when needed. Time and time again it has proven to be the best decision I have ever made.

Our focus on innovation and exploring new ways to design speakers has always driven us to new levels. This approach has put us at the forefront with the best speaker manufacturers and also differentiated us from the competition.

A lot of the credit for that has to go to the many people at Morel. Without everyone here we would not have achieved such a high degree of success today. I could not have done all of this by myself. I have been blessed to meet and work with some of the most amazing, hard-working individuals throughout my life. Our production workers, designers, engineers, salespeople, managers, and our global business partners abroad are passionately working to promote our company.

Photo-2-MorelSHANNON: As Morel’s founder and principal designer for many years, what has been your best experience?

MEIR: The joy of designing a product, manufacturing it, and following its acceptance in the marketplace is something very special to me. The thrill and excitement of seeing other people enjoy our creation and design is a feeling that revitalizes me with the energy and drive to work on the next project.

SHANNON: Your son, Oren Mordechai, is now responsible for Morel’s unique design. How did that come about? Did you encourage his interest in audio?

MEIR: Oren grew up practically in the factory, because that is where I spent most of my time. From a very early age, he loved to be on the production floor and try everything. I would not say I encouraged his interest—he just loves it as much as I do. I am lucky to say that today he is doing excellent work developing new products, venturing into new materials and innovative designs that have received industry recognition and many prestigious awards worldwide. There is no bigger satisfaction for a father than to see his son following one’s lead and continuing the tradition.

SHANNON: Are you working on or planning any new audio innovations?

MEIR: We are always working on various projects. There is never a dull moment in our Research and Development department. Since Morel caters to the home audio, car audio, and raw drivers market segments, it seems we always have new products to release.

Our most recent innovation for the DIY/OEM segment is the Ti series, which employs titanium as a bobbin (former) for our oversized coils. The new Titanium series presents very special sound characteristics and parameters that enable speaker designers to achieve better resolution and dynamics in smaller enclosures. We are also developing new magnetic systems and chassis structures that will be implemented in future products to be released later this year.

SHANNON: Your dream has been to create the perfect loudspeaker. What achievements have you made along the way and how close are you to fulfill your dream?

MEIR: The dream of creating the perfect loudspeaker can only be a dream. Over the years I have learned that in the loudspeaker field, which is partly “science” and partly “art” there is no such thing as “perfect.” My ambition is to create a speaker that appeals to the largest audience possible, while reproducing music in its most natural and authentic form, free of any distortion.

Only those who have experienced speaker building can understand the obstacles and compromises that have to be made in order to achieve this objective. Even with 38 years of know-how and a fully capable manufacturing facility, we still struggle to overcome the physical boundaries and acoustic challenges to achieve the sound we want.

SHANNON: What do you see as some of the greatest audio innovations of your time?

MEIR: There were many, but the one that transformed the industry is the transition from analog to digital. I never liked the format of a music record, as it is bulky and highly vulnerable to being damaged. At the same time, this format produces high-quality sound. As a child, I always thought this format had to change. The shift to CDs to complement, you might say, the vinyl record suits me. But it seemed to me a radical change at the time.

Whether you like it or not, nobody can refute the fact that the digital age has made music more accessible to people. Because of the new digital formats, the interface that people use today can be very common, ranging from a high-end CD player, digital streamers, or smartphones, and so forth. That’s remarkable.

SHANNON: Do you have any advice for audioXpress readers who want to build their own sound systems?

MEIR: You do not need to have a speaker company or an engineering degree to design and build good speakers. I began as a hobbyist like many in your audience probably. Reading, researching, and experimenting with different components and ideas were the only ways I was able to learn what it takes to build a good speaker. In today’s digital culture the amount of information available is almost infinite; use it to your advantage.

Keep your designs as simple as possible. Some will make you believe that a complicated crossover is a must for a good speaker to perform well. I have always spent most of the time developing quality drive units. Using quality components will minimize the need for corrective measures when you build your crossovers and cabinet.

As with anything, have fun doing it. Put your soul and heart into it. I was lucky enough to be able to transform my passion for music and building speakers into a successful business. It may happen to you. aX

Q&A: Geoff Boyd

Geoff Boyd is the managing director of Coleridge Design Associates.

SHANNON BECKER: Tell us a little about your background and where you live.

GEOFF BOYD: I have lived in San Jose, CA, since 2006. But, I hail from the Caribbean and spent most of my life living in UK. I am a 1970 Commonwealth Scholar and Physics and Chemistry graduate of the University of Leeds, West Yorkshire, England,  with post-graduate and post-doctoral research experience in Material Science at the Oxford University, Oxford, England. Leaving academia in the early 1980s I co-founded Memotech, one of the UK’s leading first-generation PC companies. I then led NXT, the company that introduced the world’s first computer interactive Videowall display systems, which included marketing and selling these high technology display systems into Japan.

In 2010, after more than 10 years at NXT specializing in new business development, technology innovation, and intellectual property licensing, I rekindled my entrepreneurial activities and founded Silicon Valley-based Coleridge Design Associates, which has the objective of building a team of designers, scientists, and engineers who specialize in creating intellectual property (IP) by invention and innovation aimed primarily at the consumer electronics (CE) and green energy (GE) markets. At its core is “Invention by Design” rather than “Invention by Serendipity” with the skill and experience to recognize the difference between a trip to Brighton (the seaside) and a trip to Mars.

SHANNON: What was your first personal project? Why did you build it? Is it still in use?

 

GEOFF: My exposure to electronics was as a postgraduate student in the
Department of Metallurgy, Oxford University, where those so inclined built their own electronics equipment for lab experiments. I took to this like a duck to water and became quite proficient at electronics design and construction as well as sheet metal work for enclosures. My first personal project was to build a functioning version of Peter Walker’s Quad 405 current dumping amplifier. The design with full schematics was published in a December 1975 issue of Wireless World. I was fascinated with the concept of the reactive bridge balancing technique used in the design. In fact, I remember doing a second-order calculation to fine tune the inductor’s resistance of the bridge. I added Douglas Self’s advanced preamplifier with discrete LED-biased op-amps, which was also published in Wireless World in 1976 as well as a discrete Class A headphone amplifier also published at the time. I laid out the PCBs using the “pen and tape” method and etched it in the lab. No purchased kits here! I fabricated the sheet metal enclosure under the expert tutelage of John Short, who ran the student workshop in the Department of Metallurgy at Oxford for many years. This integrated amplifier had a pride of place in my living room for many years. It eventually gave way to a Yamaha AV receiver over 10 years later.

SHANNON: You have more than 30 years of experience in technology and audio visual innovation. How did you get started?

GEOFF: In 1978 I moved from the Department of Metallurgy to the Engineering Department at Oxford University as a post doctorate researcher in mechanical properties of materials at elevated strain rates. This required recording data for tests lasting a few milliseconds with data rates at tens of MHz. Though my passion for music and interest in audio electronics remained, my electronics interest and expertise shifted to computer and memory electronics design.

SHANNON: What made you venture out on your own and start Coleridge Design?

GEOFF: I started as an entrepreneur during those heady days of the first personal computers in 1979. I plotted to start a hardware and software business with another researcher at Oxford, Robert Branton, who worked with the programming research group at Oxford. It wasn’t a difficult decision to branch out because at the time Margaret Thatcher had just become prime minister and the cushy jobs at the universities were disappearing fast. By 1981, the writing was on the wall and tenure was going to end, so I decided to forget about an academic career and start my own tech business. Our first business, Memotech, was making add-on memory packs for the Sinclair ZX81. Initially, I designed the products while still at the Engineering Department and then I jumped ship as soon as the business roared to a massive success.

The story of Memotech is interesting. The ZX81 came with 1 KB of memory, and the first thing the user needed was a 16-KB memory pack. When dynamic random access memory (DRAM) ICs were purchased, they needed to be fully tested in circuits with demanding tests, which typically lasted 3 to 4 min. In the UK, there were two contract manufactures who made Sinclair’s add-on packs—Thorn EMI and AB Electronics. They used GenRad testing machines that cost over $1 million each. You couldn’t speed up the test, so the throughput of these machines was limited. Memotech couldn’t afford these machines to test its MemoPaks, as they were called, so we built our own testing rigs using Intel 8048 8-bit microcontrollers with a complete memory test system that cost us less than $500! The MemoPaks were housed in black anodized extrusion enclosures and had a reputation for quality. Needless to say, Memotech cornered the market on Sinclair ZX81 memory add-ons, and we were able to build a multimillion-pound business within one year. I remember that we had UK retailers WH Smith, Boots, and others on allocation, and we could sell everything that we could make. In the US, the ZX81 was launched as the Timex 1000, and we experienced explosive growth and success. I hastily left the university and never had the time to submit my D-Phil thesis from the work in the Metallurgy Department at Oxford, although my research was peer reviewed and published at the time.

At Memotech, we thought all we had to do was produce a first-class product with a great design and specifications, and the buyers we had on allocation would come to us. So, we designed and manufactured the Memotech MTX 512 home computer, which was launched in 1983. We were competing against BBC Microcomputer System and never stood a chance in the UK. The buyers never came and the level of marketing required was beyond our resources, so our backers eventually pulled the plug in 1986. That was a huge lesson. I bought what was left of the business and relaunched Memotech Computers using high-resolution digital video technology that had been developed at Memotech to a new market of videowall technology. We dominated the supply of videowall controllers for nearly 10 years, from 1986 to 1995.

Another lesson I learned from 1995 to 1999 was that “things change.” We miscalculated, thinking that to have large LCD-TVs one would need to “tile” smaller displays. In 1995, it was generally accepted in the display industry that one could never manufacture LCDs larger than approximately 23” diagonal because of glass-handling issues. Another bit of wisdom at the time was that LCDs would quickly transition from amorphous silicon active matrix LCD (AMLCD) to low-temperature polysilicon technology (LTPS), which would mean the driver electronics used with AMLCD would be eliminated. And a further bit of wisdom at the time was that the yield of LCDs would never exceed about 70%. I launched Coleridge Design in 1996 to create a business to tile partially defective LTPS 23” to 25” LCD panels into 100” very large screen flat panel displays (VLS-FPDs) based on these false assumptions.

Needless to say, the business never took off as technology changed making all three assumptions on which the business was based wrong. And in 1999, I joined NXT, the UK flat-panel speaker IP company, as a display consultant to launch SoundVu where “the screen is the speaker.” For 10 years, I worked at NXT with a fabulous team of colleagues all passionate about music and sound reproduction. I worked primarily in IP business development and sales. It was a valuable experience that brought me in contact with all the great audio and consumer electronic companies of the world. I did contribute on the technology side and have a number of NXT patents to my name, but it wasn’t my day job. In 2006, the bulk of the NXT business moved to Hong Kong to be closer to its licensees and I moved to Silicon Valley to be closer to the OEMs that were licensee targets. By 2010, NXT was retrenching, having failed to make a lasting impact with its IP licensing business model, and started moving back to UK. This was my cue to relaunch my entrepreneurial career in Silicon Valley. Coleridge Design in San Jose, CA, was launched at the beginning of 2010.

SHANNON: Tell us about your work. Do the models you used 30 or even 20 years ago still function today?

GEOFF: The Coleridge Design plan is to develop IP mainly in consumer electronics audio and sound reproduction as well as in printed electronics and green energy with the “user experience” as the guiding force. I call it “inventing by design,” where I call on my extensive experience in science, technology, engineering, and mathematics (STEM) to lead a team charged with addressing neglected technology needs.

The entrepreneurial model we used in the past was based on gut feelings. We make a design and a product then put it out there to see how it sells. If the product and price was great then it would sell with moderate PR and marketing. The marketing was entirely business-to-business (B2B) or business-to-consumer (B2C), depending on the product and the target market. The Internet changed the model slightly in the last 20 years but not significantly. Today, we have a fundamental shift with the advent of social media, which in effect means that our marketing effort is dominated by consumer-to-consumer (C2C). Another significant change is the advent of Kickstarter and crowdfunding. In the context of making and taking products to market, I view it as an extension of C2C where you can test the market before you build your product. Our case with Coleridge Design and the aCUBE is a classic case of using Kickstarter to test the market and fail early.

The aCUBE uses 4.5” BMR full-range loudspeaker drivers, beautiful handmade clear cast acrylic 6.5” cube enclosures and the latest Class-D amplifier technology from Maxim Integrated.

SHANNON: Your most recent innovation is the aCUBE. How did this design come to be? What makes it so unique?

GEOFF: In about 2004, Dr. Graham Bank, a colleague at NXT, made a breakthrough in loudspeaker technology inventing the balance mode radiator (BMR) loudspeaker. The BMR is a full-range loudspeaker driver, which provides outstanding performance. My personal view is that this is the most significant advance in loudspeaker technology since 1925 when Rice & Kellogg invented the loudspeaker as we know it today.

BMR technology has appeared in many stand-alone loudspeaker products. However, these have largely been in either expensive Hi-Fi or in performance compromised speaker systems. The advantages of BMR speaker technology are many, but primarily relate to its pinpoint accuracy yet wide dispersion and extended frequency range. Together this allows the design realization of a high-performance, single-drive system such as the aCUBE.

This project takes the 4.5” BMR full-range loudspeaker drivers from CSS, a company owned by my former NXT colleagues, Dr. Graham Bank and Jon Vizor, and marries these drivers with beautiful handmade clear-cast acrylic 6.5” cube enclosures and the latest Class-D amplifier technology from Maxim Integrated. The result: The best in-class performance speakers optimized as near-field active loudspeakers that are stylish, exceptional quality, affordable, and convenient.

The use of acrylic is quite by accident. I have tended to use aluminum extrusions in most of my designs. The MemoPak 64K, the Memotech MTX 512 computer, and the Memotech DDFS videowall controllers were all made with black anodized aluminum preferably brushed. So we designed and prototyped a range of BMR speakers in anodized aluminum enclosures. However, before we made the protototypes, we built some acrylic enclosures as proofs of concept to test the BMR drivers from Cotswold Sound Systems. They sounded fabulous. However, when we used the aluminum prototypes, the enclosures rang like a bell and we had to take drastic measures to dampen the sound. Due to my materials science background, I realized that the acrylic sounded fabulous because of the material’s high internal damping over the entire audio bandwidth due to viscoelasticy. That was the reason the relatively thin walled enclosures sounded so well. Once we decided to make the aCUBE out of acrylic sheet, we had to find a supplier who could make perfect cubes using CNC and the latest techniques in bonding and polishing. The beauty in cast acrylic sheet is how it renders the light through perfect edges.

I have to confess, the aCUBE Kickstarter project was a bit of a Trojan horse in an attempt to gauge whether the consumer electronics market has an appetite for a new audio brand in quality sound reproduction and whether crowdfunding is a viable route to launching such a brand. It didn’t take long to see that in its present form, the Coleridge Design brand will not be a viable vehicle for launching the groundbreaking, disruptive audio technologies as I envisaged. Another valuable lesson learned from this early failure is that very little has changed and launching a new brand is still all about marketing, albeit nowadays C2C social media marketing.

The Lunatik Touch Pen, available in several different colors, is currently in prototype development. The accessory can be used both as a regular ink pen and as an implement for your tablet

SHANNON: Describe your touch-pen technology and how it works.

GEOFF: A couple of weeks after I got my first iPhone in 2007, I designed and built a capacitive-touch pen using conductive silicone rubber to emulate the finger. There are two requirements for a capacitive touch pen. The first is that it must form a flat conductive area of about 0.5 to 1 cm2 on the touch glass surface. The second is that this conductive area must be electrically connected to an electrical “sink” such as the human body or “large” lump of metal. The first touch pen that we built had a mild steel core of about 100-mm long × 3-mm diameter embedded in a silicone rubber “pen” about 110-mm × 8-mm diameter. We built a few hundred prototypes, but it wasn’t viable because there was no IP protection.

So we came up with a design in which the rubber grip of a gel pen was made out of conductive silicone rubber and modified so that when the pen refill was retracted the silicone rubber tip would collapse and could be used as a touch pen even when the pen body was plastic because the grip would conduct through the fingers.

Coleridge Design licensed the technology exclusively to Scott Wilson at Lunatik.com who launched it on Kickstarter, his second project after his very successful TikTok project that created the Lunatik Brand. (For more information, visit www.kickstarter.com/
projects/1104350651/lunatik-touch-pen-the-evolution-of-thestylus.)

This is the licensing business model that we generally want to use for the IP we develop. The key is to make a whole product that is ready for market. Most of the time it is not that easy because the technology is not a “whole product” and needs one or more entities in the supply chain to complete the product. In many cases, it might be an OEM or brand to take the product to market as well as suppliers to change the way they make products. That is very hard and needs to be driven by the OEM. That was the reasoning behind trying to make Coleridge Design an audio brand. If one cannot take it to market then one has to make it worth the while of the OEM or brand to get on board. That generally means some degree of exclusivity. Say a time-limited exclusivity or even an outright sale or fully paid up license.

SHANNON: What do you see as some of the greatest audio innovations of your time?

GEOFF: In the last 40 years, we have come a long way in improving the user experience but only if we use convenience as the main metric. To speak to that, I would say three of the great innovations of “my time” include: The Digital Audio revolution, which has led to surround sound and iTunes; the Class-D filterless audio amplifier; and distributed mode loudspeaker (DML) culminating in Dr. Graham Bank’s BMR. However, in so many ways, we have gone backward in the user experience of audio, mostly in the name of convenience. I recall valve amplifier systems from the 1960s and 1970s with very large speakers, some of them built into the users’ homes, which outperform most systems I have heard in the last 20 years.

How do we get great-sounding audio out of relatively “small” enclosures? I clearly remember an encounter I had with Michael Gerzon, who it would be reasonable to say invented surround sound. It was sometime in 1975, just after he had published his work on surround sound in Wireless World in December 1974. I was invigilating as a student’s part-time job on Friday evenings at the Radcliffe Science Library in Oxford and Michael, who was at the Oxford Mathematics Institute, had reserved some books on Matrix theory. I spotted his name on the ticket and when he came to collect his books I pumped him with questions on surround sound. I came away with two pieces of information, which I clearly remember to this day. The first was that the minimum number of speakers required for full surround sound would be six at the corners of an octahedral arrangement. Two at the top front, one at the bottom center, two at the bottom back, and one at the top center. But the bad news, he said, was that for the equations to work they all had to be full-range speakers (i.e., including bass). This has remained with me for 40 years.

SHANNON: Are you currently working on or planning any other speaker-related projects?

GEOFF: Coleridge Design has been developing IP on three audio related projects:

A personal surround-sound headphone system (PX3) based on design work we did on motorcycle helmet audio (www.youtube.com/watch?v=ilfSA_FoiaU). The new development seeks to achieve the same Helmet-Blaster unbelievable surround-sound performance in similar form factor and power requirements as conventional headphones.

The magnetless voice coil actuator (M-LVCA), which is a green initiative to eliminate rare earth magnets in loudspeaker motors at reduced cost without loss in performance and increase in weight. This is based on recent advances in insulated iron soft magnetic composites (SMCs) coupled to audio digital signal processing. It is scalable to all sizes of loudspeaker motor. There are possible spin off applications in electric vehicle technology

The extended range flat-panel bass (flatBASS) loudspeaker with active shallow enclosure technology. My 1975 encounter with Michael Gerzon makes this what I consider the holy grail of loudspeaker technology!

SHANNON: Can you recommend any useful new parts or promising technologies to audioXpress readers? Anything you’re using now that you think readers should know about?

GEOFF: I would recommend Graham Bank’s BMR loudspeaker drivers from Cotswold Sound Systems mounted in naturally damped “thin-walled” acrylic enclosures. Thin-walled clear cast acrylic sheet typically 4-mm thick for 3” to 4” cubes, say 6-mm thick up to 6” to 8” cubes and say 10-mm thick up to 12” to 15” cubes.

There has been rapid improvement in lowering the cost and increasing the performance of the latest filterless class-D amplifiers from Maxim Integrated and Texas Instruments (TI). They are very efficient and worth evaluating in new designs but good quality power supply design is critical. Also the bridge tied load (BTL) output configuration of modern Class-D is pretty much mandatory but care must be taken to switch both ends when using speaker switch boxes.

Another new technology worth considering in modern audio designs is the use of supercapacitors from, say, Maxwell and PowerStor, particularly for battery designs, which are now really viable with the new super-efficient filterless Class-D amplifiers. Audiophiles love the concept of a battery-powered audio amplifier! Quiescent current of these amplifiers is the key efficiency metric. Supercapacitors have drawn much attention in recent years due to their high power density, reversibility, and long cycle life. They are found in a wide range of applications from smart phones to electric vehicles and the rapid price reduction in recent years has made them affordable in applications like this.

These low-cost supercapacitor devices are typically 2.5 to 3 V maximum so one needs to incorporate active balancing when these devices are used in series. For example, AA batteries would be configured in series for relatively high peak powers into 4-Ω loads from typically 15 or 12 V (primary or rechargeable respectively). However, particularly when partially discharged, these battery stacks are very poor at delivering the intermittent heavy-power transients required for high quality audio. A series bank of active balanced supercapacitors can supplement the battery pack and completely counteract this.

SHANNON: Do you have any advice for audioXpress readers who want to build their own sound systems?

GEOFF: In the words of Nike, “Just do it.” I don’t mean to be flippant, but I firmly believe that you really learn when you make stuff. I include circuit simulations in “making stuff.” I tend use TI’s TINA-TI and other free tools for analog simulation. I don’t breadboard until I have it working in simulation. But, in the end, it has to be prototyped and tested. In analog audio electronics, this is getting really hard as we move to smaller fine-pitch ICs. My advice is to make use of manufacturer’s reference board designs and take a stab at laying out your designs using the many free tools available from PCB fabricators. I tend to use old fashioned axial and radial devices for breadboarding small sections, but more often than not, the working simulations allows one to go straight to SMD PCBs, typically 0603 passive devices for prototypes and preproduction only moving to 0402 if board space is an issue. Another golden rule I have for analog audio is to always use full differential designs, particularly when interfacing to digital ICs with analog outputs. aX