ATRAD’s Adam Rosner is passionate about creating bespoke hand-built stereo vacuum-tube amplifiers and related devices. He explains all to RICHARD VAREY.
I admire audio artisans and am a fan of a growing body of their creations, and I also favour local produce, so I’ve been taking a look at ATRAD Audio Design.
Some music listeners are content to tread the familiar path of mass machine-made products. Others, like me, cherish the hand and heart of the creator on a crafted artefact.
Adam Rosner hopes that the old-fashioned way of listening to music with an amplifier and hi-fi speakers isnโt quite dead yet.
He creates bespoke hand-built stereo vacuum-tube amplifiers and related devices under the name ATRAD, signifying โanalogue traditionalโ. Heโs a self-taught designer and builder of valve amplifiers who has been interested in electronics since childhood. His father was a recording engineer with Decca in London, then with EMI in New Zealand, so he was exposed to hi-fi at an early age. Like me, as soon as he started earning money, he started buying gear and slowly improving it.
I asked Adam how he got into amplifier building and about his design ethos. Here’s what he told me:
I became somewhat enamoured of the sound from valve gear about 20 years ago, but for whatever reason never took the plunge. Sony and then Plinius were my solutions for a while.
Then in 2016 I decided to dive in the deep-end and resurrect my electronics skills by building a no-compromise design valve amp, which was probably a foolhardy first project, yet it worked fantastically. After that I wasnโt going to build any more, but then a friend wanted an amp so I designed one for him, then I had another project I wanted to try, and so on. All the while I was picking up skills myself, hence my continuous improvement ethic. Each project must be better than the previous.
As long as I can remember, I’ve been interested in electronics. I didn’t make it my career though. I never studied it or gained any qualifications in the subject. It was just a life-long, dormant interest. Also, I’ve always been interested in audio โ I was bitten by the hi-fi bug at a very young age.
As soon as I started earning money, I began my quest for equipment to satisfy the desire for pure sound. A variety of black-box Japanese equipment served my listening purposes, usually mated to well-mannered English speakers. My taste has always been toward the pure and clear sound with pinpoint imaging, instead of blasting out phat beats!
By a varied path I came to be exposed to some rather delicious valve gear a few years ago which led to an instant epiphany… despite my extreme cynicism and scepticism about audiophiles (who at the time I saw as guys who just wanted to brag about their expensive gear), this valve sound was something that I couldn’t just condemn as pretentious.
This was the fertile ground in which the idea of building my own no-compromise design, valve/tube-based integrated amplifier took root. To do this I’d need to pick up a lot of learning, read a lot of books, and fill in a lot of missing gaps in my knowledge. Also I’d need to build a few development circuits. Over the course of several months, I went on a slow mission to pick up the tools and equipment I needed, work through lots of books and reference material, and evaluate different software solutions for circuit design and simulation, chassis design, and so on.
The result was my first ever creation โ a big, ambitious amplifier that, in hindsight, now seems a risky project, but it is now my daily driver, feeding my big KEF floorstanding speakers, as well as producing a good amount of heat in the winter months!
I started a blog to chronicle the progress as I started at the ‘ambitious but clueless noob’ level, slowly picking up knowledge and skill along the way, through the design of my project.
Since building that big amp for my own use, I then had a friend approach me to build another, which I did, then I created a tone control, then another amplifier, and so on. Now I’m taking orders.
Each project builds on the previous and introduces some refinement. My goal is that each project is better than the previous.
I do the circuit design, make up my own PCB layouts, then etch and drill and populate the boards in my home workshop. Also I design the layout file and drill the cases, while a friendโs CNC and laser etching machine does the cosmetics.
I decided to set up the atrad-audio website last year after a couple of expressions of interest from people, largely as a portal to engage with potential customers โ the focus and target audience of it is quite different from my blog. I also built a demo unit (the Matariki amplifier) with a lot of attention paid to the aesthetics, to be able to take to different demo situations if needed.
A big problem with valve gear for the uninitiated is the power level: There is an appreciable section of the population whose only understanding of an amplifierโs worth is its power output. Explaining that itโs 15 watts per channel is usually enough to discourage those who arenโt particularly knowledgeable. I address this on the FAQ on my website.
I donโt apply a particularly large mark-up to my projects. Given that absolutely everything is assembled by hand (right down to hand-made PCBs), I think my hourly rate turns out to be something like 30 cents or thereabouts! But, Iโm not trying to make a profit beyond making what is essentially an expensive hobby self-funding.
The one thing that has truly delighted me though, is the sound quality I get from this gear. It truly lives up to my expectations, and Iโm quite used to peopleโs jaws dropping when they come around to listenโ.
Descriptions and photos for the several projects completed can be found in the Projects Gallery on the website. Iโm looking forward to auditioning a Matariki amplifier that is currently being built for a review here at Witchdoctor.
Adam Rosner is based in Porirua and can be contacted via email onย [email protected]