Vintage Tube Amplification During a Lockdown, Part One

Vintage Tube Amplification During a Lockdown, Part One

Written by J.I. Agnew

There are some things that you just have to do at some point in your life. After reading Zen and the Art of Motorcycle Maintenance by Robert M. Pirsig and Jack Kerouac’s On the Road as a teenager, one of these things I aspired to do was take a road trip across America. Growing up in Europe, I started with smaller-scale road trips, working my way up to driving from the Atlantic coast of Britain to the borders of Asia and from the North Sea to the Mediterranean.

But the urge of driving across America still remained strong, so a few years later, armed with plenty of driving experience and enough mechanical aptitude to keep carburetors and contact breaker points adjusted, I finally got to drive from the Atlantic coast of New York to the Pacific coast of California and from the Canadian to the Mexican borderlines. I could go on and on telling stories from these road trips, but the one thing that had a huge impact on me while traveling across the US was getting to listen to and see the insides of several American high-fidelity tube amplifiers from the golden age of hi-fi, from 1950 to around 1960.

Their build quality was phenomenal! Heavy-gauge all-metal enclosures, point-to-point wiring, components that were generously rated for their applications, substantial transformers and plenty of attention to detail – not to mention the tubes themselves, from tube companies like RCA, Sylvania, General Electric and Tung-Sol, or even imported Telefunken, Mullard and Amperex vacuum tubes. The overall internal appearance of these components was closer to that of laboratory measurement instruments (think tube-era Tektronix) than the other, more mundane audio equipment out there.

I saw and admired the work of several manufacturers, such as Fisher, Marantz, Dynaco, EICO, McIntosh and many others, but the one I really just had to own was one of the 1950s H. H. Scott tube amplifiers. However, although I have worked on all of these amps and many more over the years, I had never actually owned a Scott. (Well, admittedly, I did own a solid-state Scott at one time, but this was already in the printed circuit board era. It just wasn’t the same as the older, pre-circuit-board amplifiers.)

VIntage Scott 299 ad.

As I got deeper and deeper into the professional side of audio over the years, I became fascinated by the significantly more massive theater amps by Altec and Western Electric, before eventually being won over by directly-heated triode tubes in their lower-power form (types such as the 300B, 2A3, 45 and others).

I had already developed a strong preference towards ultralinear output stages over pentode stages, and triodes just wiped everything else off the map for me, at least for anything other than guitar amplifiers. I had almost forgotten my early fascination with Scott amps and had not seen one in a few years – up until the pandemic struck.

Over this past summer, I had been incredibly busy building a new, and I’d like to say world-class audio facility (an ongoing project which I shall be presenting in further detail in the near future), which involved shaking up everything; frantically moving equipment around from lab to home to new facility; and building, adjusting, modifying and moving things around some more. But then came the lockdown, and while our work on the new facility had progressed well in anticipation of it, I suddenly realized that I was stuck at home, with a pair of decent loudspeakers and a good turntable, but no amplifier and no phono stage! All of the amplifiers and phono stages I could possibly use were now stuck in a different building, which, according to the local implementation of the lockdown, was now out of reach until the COVID-19 curve was flattened! Reality started to look pretty grim. Aside from the seriousness of the pandemic, was I to just endure life without recorded music for a while?

Or would I attempt to outrun the highway patrol, hoping to be able to go to the studio and bring back an amp and phono stage, without ending up playing “Jailhouse Rock” to the entertainment of my fellow inmates, guards and warden?

Realizing that my 40-year old Volvo weighs about twice as much as the V8-powered muscle car Kowalski was driving in the film Vanishing Point, while having about half the motor, I decided to try a more subtle approach. Horsepower concerns aside, Kowalski’s biography had a rather abrupt and untimely ending for my liking. He did not bring back an amplifier or phono stage and I would be even less likely than him to encounter scantily-dressed hippies riding mopeds in the middle of the desert, not least because there is no desert nearby (and we’re very much in the wrong decade for this kind of thing still being in vogue). Upon briefly contemplating the sheer futility of negotiating with a highway patrolman on whether high-fidelity audio was a basic necessity for survival – a patrolman who has already had to endure several hours of horrible weather and in all probability, a lifetime of listening to recordings of questionable fidelity on plastic table radios – I quickly concluded that it would be more prudent to stay put and have a look at my stack of parts at home.

J.I. Agnew's Scott 299. J.I. Agnew's Scott 299.

I had enough directly-heated triodes on hand to produce several kilowatts of power while heating the house and water for the shower at the same time. I also had plenty of good driver tubes, enough of a supply of rectifier tubes to power all the Christmas decorations in Manhattan with DC if needed, and a wide selection of exotic output, inter-stage and power transformers – but very few small-signal tubes. I could put together a good pair of power amplifiers in an afternoon, but I’d still be stuck with no phono stage!

After giving up all hope of designing a phono stage that could pass for “high fidelity” around what I already had in stock, I also realized that by the time I designed something that would do the trick, put together a parts list, placed an order for needed parts and waited for them to arrive, I’d be several weeks into a music-less lockdown. And I’d still have to build it and test the phono stage.

I picked up my guitar and started wailing some miserable blues…then, remembering my experiences of years past it suddenly occurred to me: H. H. Scott! They had made vacuum-tube integrated amplifiers that contained a phono stage! Granted, these were not up to my usual standards of triode-only monoblock amplifiers and separate preamps, but if I could find one not too far away, this could be my only chance of being able to enjoy recorded music again soon. Besides, my mood suggested that I’d mainly be listening to Howlin’ Wolf and Muddy Waters recordings for a good while, so absolute fidelity was perhaps no longer my top priority. I just had to get that listening system up and running as quickly as possible to begin with, and consider any improvements later.

Unfortunately, there aren’t that many Scott amplifiers in Europe and even fewer that happen to be up for sale, as fully functional items, when you need them. But I was in luck! There was a Type 299 stereo integrated amplifier in Poland, on one of the popular auction websites, which could be shipped quickly. What sealed the deal for me: I’ve traveled to Poland a few times and I can assure you that one can find excellent food there, so I decided to go for it. After all, audio equipment and fine food appear to be inextricably linked. This is not to say that British audio equipment is lacking finesse, even though beans on toast certainly does, but I shall leave the discussion on the impact of gastronomic refinement on amplifier output stage biasing tendencies for a future piece.

J.I. Agnew's Scott 299, top view. J.I. Agnew's Scott 299, top view.

The H. H. Scott Type 299 was introduced in 1958 and was the first stereo integrated amplifier produced by the company, which was already manufacturing high quality monophonic power and integrated amplifiers since 1948. Both Hermon H. Scott (the company’s founder) and Daniel von Recklinghausen (vice president of engineering) were MIT graduates. Judging by the build quality of the 299, they both had a passion for their craft. The output transformers were designed and wound in-house, along with the chassis and even the machined aluminum knobs. The 299 uses a pair of 7189 output tubes per channel, which are similar to the EL84/6BQ5 but can withstand a higher plate voltage. The Type 299 indeed operates the tubes with 355 volts on the plates and 300 volts on the screen grids, exceeding the published maximum ratings of the EL84. Many of the current-production EL84 offerings will not take kindly to this, so be warned if you have a 299 or any other amp calling for the 7189 and are contemplating a power tube substitution.

Despite the lockdown in its various forms in different parts of Europe, the amplifier made the trip in just a few days and I was now finally the proud owner of an H. H. Scott tube amp! Another item ticked off my “to-do-in-this-life” list!

So, could I listen to music now? Not so fast! This is a 62-year-old amplifier and regardless of what online sellers claim, I do not take for granted that anything of this nature is functioning properly, even if it appears that it might be at first look.

In Part Two, we shall have a look at what it takes to bring elderly amplifiers back to their former glow!

Postscript: creative writing aside, my heart goes out to all immunosuppressed and chemotherapy patients out there. These are already extremely challenging situations even without having a pandemic on top. It is them who are really struggling for survival now. By comparison, my sound system concerns are just luxury problems. The audio world has also suffered a great loss: On December 17, Tim de Paravicini of Esoteric Audio Research passed away aged 75, after a remarkably long career in audio.

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