In a production-line world, what room is left for hand-wired audio amplifiers? Plenty, given guitarists' fondness for 'authenticity', reports E&T.
In an age when the majority of music released has been recorded, mixed, processed, distributed and consumed almost entirely in the digital domain, why is it that, when it comes to amplifiers, so many guitarists are obsessed with the primitive - some engineers would say obsolete - technology of the 1950s and 60s?
Tag boards, point-to-point hand-wired circuits, valves of all shapes and sizes, mustard capacitors, retro cloth and tolex coverings: these are the key elements of design that quicken the pulse of the vintage-amp enthusiast.
For the discerning guitarist, a hand-wired valve-powered low-wattage amp represents the pinnacle of sound, offering an almost zen-like simplicity and purity in its circuitry design and signal flow. Like retro-winged moths to a valve-powered flame, guitarist of every stripe continue to be drawn to the old ways.
How is it that this desire persists today? Why, in the 21st century, are major manufacturers still laboriously hand-wiring valve amps, using 50-year-old circuit designs?
Shane Nicholas, senior marketing manager for Fender Guitar Amplifiers, has the simplest answer: "Some folks want amps that are built the Leo Fender way, the 1950s way. Most guitarists have returned to the basics: a great-sounding tube amp and a couple of stomp boxes."
Fender, Vox and Marshall
Companies like Fender, Vox (makers of the venerable AC30, the Beatles' touring amp of choice) and Marshall (enjoyed by everyone from Aerosmith to ZZ Top) all currently have a hand-wired element to their product catalogues, often for very different reasons.
Vox had a straightforward reason for resurrecting historic designs to create its hand-wired Heritage range: the company's 50th anniversary in 2007.
Meanwhile over at Marshall, Peter O'Neill, assistant head of R&D, says the company sensed the winds of change as players began looking back to what was perceived as a golden age: "To some of the guitarists who were buying amps in the 1960s and early 1970s, hand-wired amps are just amps, but to a newer generation they are a rare and desirable object. As the quantity of amps on the second-hand market was drying up, people were buying imitations of early Marshall amplifiers and sometimes paying well over the odds for them. It made sense that we should start making these amps again. Why have a copy when you can have the real deal for a better price?"
Fender's Nicholas echoes this sentiment: "Back in the early 1990s, a few new 'boutique' companies introduced amps that were direct copies of Fender, Vox and Marshall. This helped to alert us that there was a market out there for high-end, hand-made amps. We knew it was time to do the '57 Twin, for example, when they became extremely collectable and pricey."
The spiralling cost of the vintage originals in keeping with their sustained popularity is the reason Mark Baier - owner of the Victoria Amp Company, which has made its name producing latter-day hand-wired replicas of Fender's 1950s Tweed classics - gives for the burgeoning reissue and boutique amp market.
"Fender's biggest competitor used to be itself - its second-hand used gear on the market," he says. "Then Fender reissuing the Bassman begat this little industry. People noticed the difference in tone and started looking deeper underneath the hood. It had the effect of arming the public with information and they consequently went looking beyond the norm."
With a ready market now beating a path to the manufacturers' doors, reviving the hand-wired tradition made good business sense on a number of levels.
Vox R&D's Ian Doggett has a twin theory as to why companies like to produce hand-wired products: "I think hand-wiring shows an ability of the company, the technical level of the staff," he says. "I also think there's a lot of marketing magic as well, because you can create an additional premium on the price for hand-wired because it has this aura of 'hand-wired is better'".
Doggett's colleague Dave Clarke (one of the designers behind Vox's Heritage AC15) gathers up the nebulous issue of end-user perception, stating: "Tone is subjective. An amp could indeed be considered more authentic because it's using original components, but that doesn't necessarily mean it's going to sound better. It might actually sound worse."
Clarke puts forward the argument that vintage amps may have their signature sound for the 'wrong' reasons: "Back in the 1960s, the components were by and large very poorly made. So you're listening to an amp that's 40 years old and all the caps are just on the cusp of drying out and the smoothing caps have gone and the mustard caps are going and everything needs replacing. You're going to have to replace it all if you want your amp working any more - you can't not have smoothing caps - and then it's going to sound completely different."
The issue of component supply is one familiar to all the manufacturers. Historically, component shortages dictated that necessity be the mother of invention, such that what might now be considered a classic amp came about purely by chance. Doggett describes how a company might "buy in a couple of hundred of this and a couple of hundred of that and put something together", going on to explain how "because of the compliance issues, you can't buy original components new anymore."
Equally, Nicholas's concern for Fender is about being able to maintain production levels: "The tricky part can be finding the right components in an age where nobody else in the electronics world cares about guitar amps. Mobile phones and laptops aren't hand-wired, you know," he says.
Marshall, on the other hand, has been luckier, as O'Neill points out: "Many of the component manufacturers from the early days are still producing and willing to supply components to us. This includes Drake, who made transformers and chokes for Marshall in the early days. This is a major boon for us as it really helps us say to people, 'Yes, this is as close to the original as you can get'."
Retro amp safety
One major headache common to all R&D departments is the clutch of safety regulations that impose a heavy burden on manufacturers, particularly EU-based companies.
"From a safety point of view, we have to follow CE approval," explains Doggett, "which is extremely stringent. Now we have to go through EMC testing for Europe as well, which is emissions and immunity. When you consider that you're paying up to $50,000 per product to achieve these certifications, that's a problem."
Mulling over the hypothetical possibility of Vox reissuing a period-correct AC30, Clarke lays out the hurdles facing the company: "We wouldn't be able to use completely original components, because we're simply not able to. The lead content would be too high. People say all the time, 'Oh, why can't Vox put in this type of resistor or that sort of cap?' Because we're not allowed. You know, the AC30s of old had a habit of bursting into flames! And they'd have done that for a reason, so we'd have to change that. Critical components for your AC30s, like the output transformers: to make them vintage correct, we'd have to have them wound the old way, and then they probably wouldn't pass insulation tests, so from a safety stand point it's just not viable to do it."
Marshall's O'Neill elaborates: "If a safety engineer looked in an original amp from 1967, he'd probably faint. We've had to make a few changes to things like mains transformer construction, mains connectivity (the old three-pin Bulgin connectors are no longer acceptable), mains voltage markings and selectors, earth bonding and the use of flame-proof (metal film) resistors in some circuit locations. Although these changes have no effect on the tone of the amplifier, they can still have an effect on the way it is perceived."
Clearly, building a reissue valve amp is far from a straightforward case of pulling a sheaf of old blueprints out of a drawer marked 'historic hand-wired'. There's also the issue of production: where and by whom.
"We have to fit in with how our manufacturer can efficiently run its production line," explains Doggett. "We use OEM manufacturing, so we have to design within the capabilities within that factory. Everything is standardised. There are key components that have to come from a certain supplier."
"We chose a certain type of handwiring for [Vox's Heritage series] for a number of reasons," explains Clarke. "We chose to use a turret board with tracks underneath, purely for power and grounding. Everything else was mounted on turrets. They look like PCBs, but they're not PCBs. The way we designed them was to make them easier to produce."
Vox uses Chinese company IAG to build its Heritage hand-wired amps and it's worth noting that they are built on the same production line as the PCB/valve AC30 Custom Classic amps, the bread and butter wedge of Vox's revenue stream.
Fender also manufactures in the Asia-Pacific region, as well as in Mexico, but the hand-wired jewels are predominantly US-made as part of the Custom Shop range.
"The assembly crew has to be specially trained, because they are soldering components one at a time. It's precise, painstaking work," says Nicholas. "Our Custom series models cost more to build than PCB amps because time is money. The circuit board in a Vibro-King takes about eight times as long to build as, say, a Super Reverb. Is it better? That's up to you. Is it different? Yes."
Handbuilt in Milton Keynes
Marshall, meanwhile, continues to build many of its amps in its UK factory in Milton Keynes. There are workers taking their time carefully handwiring flagship amp reissues like the 1974X, while colleagues sitting alongside them churn out high-volume, lower-cost PCB-based valve amps.
As O'Neill explains, "I think a lot of the success of [Marshall] is down to having all the design, manufacturing, assembly and test in one location. If there's a problem in production a member of the design team can be witnessing it first hand and working on it within a minute of hearing about it - we can react fast.
"We have a good training system and strict technique guidelines in place for the people who are wiring the amplifiers. It also helps that there are people working here in our factory that have been building amps since the 1970s, so they have been able to revive their techniques as needed."
Thus even after decades of technological advancement in other areas, the same simple hand-wiring techniques are still being practised in the name of rock 'n' roll on the production lines of the companies that first blazed the valve amp trail.
There's magic in those simple circuits, the allure of the hand-wired valve guitar amp eloquently summarised by Victoria's Baier: "The connection between the electron movement and the string movement is more intimate, more readily understandable, and that affects your playing. There is a sense of optimism that the mind can comprehend the physics of it all - passive components, simple analogue tube circuits. You can really follow the electrons through the circuit, metaphysically anyway. Yes, as electronics go, it's romantic. An op amp or transistor chip are hardly as tender and warm as a Tung Sol 5881, now, are they?"