Dave’s Corner: Debunking Tube-Amp Tone Myths

The web has put a wealth of information at our fingertips. The trouble is, all too often that information is misleading, or even hands-down wrong.

Nowhere is the pseudo-scientific babble more fetid and fertile than in the world of tube guitar amps, where players have long sought mythical ingredients that will make their own rigs just a little more magical than those of the guys who’ll be up on stage in the set that follows. Many of us discovered years ago that different components can and will make a difference in how our amps sound, but for many amp nuts that awareness has become a siren’s call to root out an entire signal-chain’s worth of golden fixes which, when strung together, will guarantee the tone of the gods.

One guy notes, for example, that his amp sounds extremely good and uses a particular make of signal capacitor. A second guy pontificates about the magic properties of those parts, even though he hasn’t tried them for himself. A third guy buys enough of the caps in question to “upgrade” his entire amp and, after making the investment and the effort, he feels obliged to rave on the amp forums about what a huge difference it made to his tone. And the myth perpetuates. It’s a familiar cycle, and if you pay any attention to the buzz on the gear forums, you’ve probably seen plenty of it.

How do we cut through the myth, the hyperbole and the pure B.S.? There’s no better route than going straight to the makers who stake their livings and reputations on the amps that they build. While some manufacturers will use “buzz of the month” parts as selling points to hype their wares (regardless of any underlying reality regarding tone and performance), each of the makers quoted here is a straight shooter who has put in the hard graft to find out what really works towards the goal of producing purely great-sounding and long-wearing tube amps. I asked each of them directly about tube-amp myths they’d personally like to help debunk in the course of writing The Guitar Amp Handbook (and the recently-released Updated And Expanded Edition), and each took the issue at face value, without any concerns for PR or self-serving prevarication. I should also add, however, that - having probed inside amps made by each of these builders — they are all using parts of perfectly good quality, none of what they say should be taken as cover for using cheap components to save money. Let’s see what they have to say.

The Myth: The most expensive parts make the best amps.

The Makers: While quality components are clearly important, most makers agree that you need to know why you’re using a part in any given position, and simply stringing together the most expensive components you can acquire doesn’t always yield the best results.

“I find that when these guys start using gold chassis and pure oxygen-free wire and all these really expensive resistors and really expensive capacitors, the more they spend, the worse they sound,” says Mike Zaite of Dr Z. “You’re not making an amp to reproduce prerecorded music, you’re making an instrument to make music. I find that some of the little warts and quirks, some of the lesser components, when married together correctly, give a better output.”

So can a guitar amp circuit be too good? Brian Gerhard of TopHat Amplification agrees that it can. “Too good is great for hi-fi, but not good for lo-fi vintage [type] guitar amplifiers. That’s why you want the proper good level, but not the best level [on paper]. To recognize a humongous point: we’re not building hi-fi amplifiers, we’re not trying for perfect replication of source material. We are producing a textured, complex, purposefully distorted sound. That is lo-fi by definition.”

Reinhold Bogner sheds further light on where the disparity between high-end components and superior guitar tone sometimes lies: “Better in engineering terms is not always better [sonically]. Like super low-noise resistors or super high-end caps, they’re not necessarily better. That’s the thing I learned early on. You see something that looks great on paper, but you try it and it sounds horrible. So there’s a big gap between what, engineering-wise, should be good, and what’s good for a guitar player. Sometimes the crappy stuff is better. A lot of times it’s like that. The imperfection gives you the coloration.”

The Myth: Hotter preamp tubes make your amp sound better.

The Makers: A lot of players feel that a higher-gain 12AX7 in their first preamp position must be a good thing, equating more gain with more goodness. Sometimes swapping to a high-gain 12AX7 does fit the bill for certain sounds, but in many situations you can actually find improvements in tone and dynamics by going the other way.

“When you drive a signal into clipping [as high-gain preamp tubes do], you lose a lot of information,” says Mark Baier of Victoria Amp Company. “The use of a 12AY7 in the front end [a lower-gain tube that’s a direct replacement for a 12AX7], which maintains integrity for the next stage, and other things, all contribute to avoiding clipping that signal too soon. For me, it all has to do with understanding that when you pick a note on a guitar, you’re creating a signal voltage that can be seen at the grid of that first tube. Varying the signal voltage can have a profound effect on the attack and dynamics of [most classic tube] amps.” Furthermore, Baier continues, a lower-gain tube makes it easier to get those dynamics working for you, whereas the higher-gain tube often slams the next stage with an all-or-nothing signal that clips too soon within the amp’s signal chain. Many notable players have achieved this with other lower-gain tube types, the late Stevie Ray Vaughan for one, who often used a 5751 (somewhere between a 12AY7 and a 12AX7 gain-wise) in his amps’ first position.

The Myth: Hand-wired circuits will always sound better than printed circuit boards.

The Makers: The labor intensity of building hand-wired amps, whether truly point-to-point or using hand-wired eyelet or turret boards, means that these often cost more than amps built with printed circuit boards (PCBs). This in itself seems to imply a superiority of tone. The thoughtful amp maker will tell you, however, that a lot depends on how and why you’re using a PCB in your design.

Mark Bartel of Tone King Amplifiers has used both hand-wired and PCB circuits in his amps, although he has often favored the latter. “I still am a big believer in a well-designed PC board,” he tells us. “I think there are a lot of advantages. I can mount the components exactly where I want them, I don’t have to rely on where a terminal strip is going to end up or something like that. I can position the wiring exactly where I want it to be, which I’m finding in some designs is more important than in others.” Bartel adds, “I’ve been using PC boards for over 20 years, and I’m at the point where I can confidently say that the type of construction I use today, which includes PC boards, has a number of advantages over conventional hand-wired techniques. I’ve hand-wired plenty of amps over the years, and I’m probably one of the few who have built the same circuit [the Imperial] both hand-wired and with a PC board.”

Steven Fryette of Fryette Amplification (formerly VHT) is another firm believer in the veracity of quality PCBs, and has some further insight on the subject: “There is the idea that circuit boards have complications in dealing with high frequencies, so when you tell an average person ‘high frequencies,’ they’re thinking ‘treble,’ but actually you’re talking radio frequencies, or ultra-sonic frequencies that don’t have any relevance to the application. So people sort of apply part of the rumor to whatever they can apply it to.” Or to debunk another critique: circuit boards are unreliable because the traces crack. “Well, why did the traces crack?” Fryette continues. “Because the company that made that circuit board designed it the cheapest way possible, with the thinnest copper possible, so that it’s susceptible to cracking. That’s not because it’s a circuit board, it’s because there’s a thing called expansion and contraction when heat and cold are applied. Circuit boards always do what the designer intends for them to do, nothing more and nothing less. So if you’ve got a circuit board that’s problematic, the problem was built in to the design, it’s not central to the quality of the material. The engineer chooses the quality of the material. The engineer chooses the application of the material or the component, and the engineer’s responsibility is to understand the limitations of that. And if you breach that, you’re going to have a reliability problem. Somebody is going to apply that to the whole school of thought.”

The Myth: One “magic” part can make all the difference.

The Makers: Most makers acknowledge that it would be great and life would be easier for them if they could plug in one magical part and make an amp instantly sound astounding. The reality, though, is at the other end of the spectrum. It’s the way that all parts work together that matters, and sometimes the individual components that do the best job will surprise you.

“There’s always the search for that one magic trick you do,” says Reinhold Bogner, “or the one pill you should take. Yeah, I’m trying to find that one pill, but at the end of the day, it’s really about paying attention to all the little details. They will add up to be a great thing. But it’s not one thing, I really doubt that.”

Holger Notzel of Komet Amplification takes the broad view: “I think these really good guys like Ken [Fischer] and [Alexander] Dumble, what sets them apart form everyone else is they have this incredible hearing. This is where it all starts. You really cannot build what you can’t hear, just like you can’t cook what you can’t taste. If you don’t taste the difference, you can’t put it together. And when you do, then you kind of don’t look at the parts the same way. If you open up a Dumble amp, there’s Radio Shack stuff in there. There’s Alpha pots in there, there’s Peavey transformers in there, but they’re the best amps ever, you know? And it’s the same with a Trainwreck. There’s not high-end silver wire in there. There’s cheap appliance wire in there, but that wire had a certain sound that worked for that application.”

The Myth: Neat wiring layouts always equate to great-sounding amps.

The Makers: On one hand, an extremely tidy wiring job might imply conscientious work in general, and that in itself is a good thing. But pure neatness in and of itself does not a toneful amp make.

“A lot of people love to see a chassis layout with wires that are real straight, and then a 90-degree bend, and then straight,” says Mark Bartel. “We used to call that ‘Manhattan wiring’ in the old days [in reference to the street grid]. I think that looks beautiful, but in two ways it is not ideal, really. From an engineering perspective, it doesn’t necessarily give you the best layout with the lowest parasitics [where noise from power lines stray into signal lines]. Just practically, it doesn’t always result in the best sounding layout. I got to talking to Bill Krinard from Two-Rock about this a lot, where we agree that sometimes the messy layouts just sound better. Of course, you can’t just make a random messy layout and expect it to sound better. The point is that wiring does have an effect on the sound, and just making it look neat on paper isn’t going to give you the best sound.”

Plenty more can be said on the subject, so maybe some of the other myths will make fodder for another installment. Meanwhile, let’s close on a piece of philosophy from Steven Fryette, which I feel addresses the subject in general very well:

“In every discipline there are hold-outs that have these old wives’ tales that they want to apply to whatever is going on. It’s universal that when you have a comfort level with a particular thing, and then you’re confronted with the new way to do that thing, there’s either just full-bore, dive in, ‘I’m all for it,’ or there’s absolute resistance to technological development. When that resistance occurs, that’s when these unsubstantiated statements about certain things get applied where they don’t apply.”

ABOUT THE AUTHOR: Dave Hunter

Dave Hunter is a writer and musician who has worked extensively in the USA and the UK. He is the author of The Guitar Amp Handbook, Guitar Effects Pedals, Guitar Amps & Effects For Dummies, The Gibson Les Paul and several other books. Dave is also a regular contributor to Guitar Player and Vintage Guitar magazines.

The Updated And Expanded Edition of Dave Hunter’s The Guitar Amp Handbok: Understanding Tube Amplifiers And Getting Great Sounds is now available from Backbeat Books.

See some of Dave's books on Reverb here.


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