how to take care of your guitar amplifier

How to Listen to and Care for Your Amp When It’s Sick

One of the most crucial parts of fixing guitar amps or anything electronic is testing electronic components correctly.

I have checked out this guide and have found it extremely good for the beginner, and as a refresher for the professional engineer.

I’ve not found such a practical guide on the internet anywhere before. There’s plenty of theory around but it’s not always easy to understand, so what Jestine Yong has done is to put together really useful, practical books with much needed techniques that will help you understand how to test suspect electronic components and fix your gear quickly and easily. […]

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The Audible Frequency Range and Describing Tone

The electric guitar is rock ‘n’ roll’s main instrument. Sure, there are rockers who feature other instruments more prominently (Jerry Lee Lewis, Elton John, the Violent Femmes, and Coldplay, for instance), but more than the drum kit, piano, electric bass, saxophone, or even the human voice, amped-up guitars define the genre.

Electric guitars can produce a huge variety of sounds, and tone—the exact timbre and quality of sound you hear when they play—is something electric guitarists obsess about. A good tone (Keith Richards playing the intro to “Brown Sugar”) can get your booty shaking almost entirely on its own. Bad tone (all those over-processed “faux metal” sounds you hear on cheesy soundtracks and commercials) is hardly inspiring. Guitar tone depends on a wide variety of factors:

The design, shape, and construction techniques of the guitar, including the length, thickness, and surface curvature of the neck, the type of frets, and whether the body is solid, hollow, or semi-hollow.
The kinds of woods (or other materials) it’s made out of, and how the various components are attached to one another.
Its age and, if it’s used, how it’s been treated and played over the years.
The design, implementation, and installation of its pickups and electronics.
The settings of all its controls, including volume and tone knobs and pickup selectors.
The type and thickness of the strings.
How those strings are attached to the guitar, including whether they pass through the guitar body or just sit on the top surface—and right down to the materials and construction of the nut and bridge at either and, as well as the design of the tuning posts.
The quality, materials, and length of the cable connecting the guitar to the amplifier.
The design, construction, and age of the amplifier.
The type and age of speaker in the amplifier.
How each knob and switch on the amplifier is set.
What kinds of pre-amp and power amp components the amplifier uses, including the type, design, manufacture, and age of those components, especially if they are vacuum tubes.
What kinds of additional effects are placed between the guitar and the amplifier (or connected to the amplifier through its internal effects loop—which can make the same effects sound different than if they were plugged into the regular input jack), how they are built, and how they are set.
The quality and materials of all the connectors between the guitar, effects, amplifier, and beyond.
The acoustics of the room or studio in which the guitar and amplifier are being played, including the effect of other instruments being played at the same time there, room materials, size, shape, furniture, and how many people are in it, including what they’re wearing and whether they’re sitting down, standing up, or dancing around.
The design, manufacture, and characteristics of any microphones used to record or amplify the guitar.
Any post-amplifier recording or amplification techniques or effects.
Any speakers (in a car, boom box, stereo, headphones, or live venue) through which the guitar sound is subsequently played.
Any background noise, hearing defects, or other things that might affect how a particular listener hears the sound.
Of course, the way the guitarist plays, including whether with fingers or a pick on the strumming hand, how he or she places and moves fingers on the neck, where the strumming happens relative to the pickups, the velocity and angle of attack when playing certain notes, and whether he or she holds the guitar in such a way that the pickups interact with the sound coming out of the amplifier for feedback effects. (Listen to the full track of “Brothers” to hear how different Stevie Ray and Jimmie Vaughan sounded when they physically swapped playing the exact same guitar, run through the same amp, live in the studio.)

And that doesn’t even cover it all. With that variety, there are also many preferences for what kind of tone people (players and listeners both) like.
Slapback to Marshall stack

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The prototype rock guitar tone is Scotty Moore’s rockabilly twang in his early-’50s work with Elvis Presley—check out “Mystery Train” for one of the first examples. That’s the sound of a Gibson ES 295 hollow-body guitar with thick nickel strings played through a 1952 Fender Deluxe tube amplifier, with a “slapback” echo effect. In early rock recordings, recording engineers sometimes created the slapback echo by putting the guitar amp inside one end of a huge empty steel water tank, with a microphone at the other end. (Yet another component of the tone.)

Perhaps the stereotype rock tone is that of the Marshall stack: a rectangular, 100-watt (or more), tube-powered amplifier “head” stacked on top of two speaker cabinets, each containing four 12-inch speakers. In this case, the guitar is a bit less important to the overall sound, although most who prefer it use Gibson-style solidbody guitars like the Les Paul or Gibson SG, with dual-coil “humbucking” pickups. Cranking up the Marshall creates a buzzing, distorted, complex, and extremely loud sound. Pete Townshend essentially invented the sound in the mid-’60s, and used it to full effect on the Who’s live version of Mose Allison’s “Young Man Blues” (even though he was actually playing single-coil P-90 pickups on a Gibson SG, through a Hiwatt amp). Later promoters of the Marshall sound include Jimmy Page of Led Zeppelin (and thus nearly every heavy metal band since), Angus and Malcolm Young of AC/DC (perhaps the purest exponents of this particular rock tone), Johnny Ramone of the Ramones, Kiss, Van Halen, Soundgarden, and most of the more recent pop-punk revival, such as Good Charlotte and Sum 41. (They don’t all use Marshalls, but amplifiers from Mesa-Boogie, Hiwatt, Soldano, and others build heavily on what Marshall started for the Who.)
Tweed and Vox

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Fender Strat and Fender Twin Amp – a classic tone combination

In between those extremes lie the tones I prefer, with more crunch and meat than rockabilly, and more sparkle and clarity than metal. Those sounds tend to come from Fender solidbody guitars like the Stratocaster and Telecaster and Fender amplifiers such as the Twin Reverb. Early Fender amps were covered in yellow tweed cloth, so some people call it a “tweed” tone—although later Fender designs are brighter and cleaner than the original tweeds. (There is also a “brown” sound, but that is associated with Eddie Van Halen and his home-modified Kramer Strat/Marshall amp—plus effects—combination.)

The more chiming British Invasion variants on the tweed sound usually came from Rickenbacker semi-hollow guitars and Vox amps, like the Beatles and Rolling Stones used, and have been compared (in their harshest versions) to “a blizzard of nails.”

Blues players such as Robert Cray (hear “Right Next Door”), clean-tone rockers such as Mark Knopfler of Dire Straits, and many country pickers also like Fender guitars and amps. Newer throwback sounds from artists like the Vines take a similar approach. I own a ’90s Fender Squier Stratocaster and a Fender Princeton Reverb amp from the ’70s, and they make a lovely noise.

My favourite example of a clean-but-crunchy Fender/Vox tone is from the Romantics’ ’80s retro-classic “What I Like About You.” The composition is nothing special, but the guitar tone alone makes the recording essential. Heck, just listening to the excerpt at the iTunes store gives me a bit of a chill. In order to achieve even an approximation of this sound (since we play the song pretty much every show), the guitarist in my band has to drive his Stratocaster through a $3400 USD Matchless DC-30 amplifier, which is modeled on the Vox AC-30. Luckily, that combination produces many other excellent tones too.
And the rest

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Of course, guitarists fiddle, and while most tones you hear on radio, CD, or your iPod are derived from the ones I describe here, they could come from nearly any guitar, amplifier, and player combination. Carlos Santana plays Paul Reed Smith guitars through Mesa-Boogie (and now Dumble) amps for his singing signature sound, while Stevie Ray Vaughan achieved his tone with Strats and a forest of Fender, Marshall, and custom Dumble amps. Some of the best sounds on record come from cheap equipment: Jimmy Page recorded the whole first Led Zeppelin album with a bare-bones Fender Telecaster and a little Supro amplifier, while Hound Dog Taylor played “Give Me Back My Wig” a few years later with a guitar and amp from the Sears catalogue.

Particularly interesting is that guitar amplification, along with high-end audio, is one of the few industries that still relies extensively on vacuum tubes (called “valves” in the U.K.), in addition to transistors or computer chips. My guitarist’s Matchless amp, for instance, doesn’t have a single circuit board: it’s all hand-wired tube circuitry, which has been unheard of in any other realm of consumer electronics since the 1960s. Even the type of tube makes quite a difference in the sound: guitarists and amp builders will tell you about the relative sonic qualities of 6V6 and EL34 power tubes, for instance, especially when they’re pushed to distortion—but when I mentioned that to my old-school electronics guy father, he said, “but 6V6s and EL34s are the same thing!” Not to guitarists, they’re not, I told him.
The Fender Stratocaster: young at 50

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Fender Precision Bass and Stratocaster guitar with Ampeg amplifier

The Fender Stratocaster guitar, which I mentioned above, is probably the source of more excellent tones (and perhaps more lousy ones) than any other. It turned 50 years old in 2004. Remarkably, it remains the world’s most popular guitar despite very few changes in its design. In its time, the Strat was not as revolutionary as the Precision Bass, from which it borrowed its body shape; nor was it as primal as the Telecaster, of which it was the more refined, Space Age younger brother.

Few other pieces of technology (other than acoustic musical instruments like pianos, hollowbody guitars, cellos, and so on) have changed as little. Personal computers made in 1999 are laughably out of date. Televisions may still use picture tubes, but their cases, controls, and electronics are nothing like they were 20 years ago. Even clothing, architecture, picture frames, and baby strollers have gone through huge stylistic changes. No modern car is identical to a ’56 Chevy—and the new Mini and VW Beetle merely resemble their predecessors, while being totally different vehicles in reality.

Guitars have changed since the ’50s, of course, and there have been thousands of different styles over the decades, from effective and beautiful to, er, questionable. Yet Fender’s supremely refined design work at the beginning, combined with the subsequent cult of vintage instruments and sounds among guitar players, means that every other electric guitar is a footnote to the Stratocaster. It also means that some of the Strat’s quirks—such as having only two Tone controls for three pickups—have persisted even if they aren’t ideal, because players have become used to them.

Fender has tried to go beyond the Strat too. Dirty Neurotic, the guitarist in my band, owned three different Starcasters (made from 1976 to 1980—see the next section for a photo of him playing his in 1994) before they were stolen, but while the Starcaster sounded great, that instrument (like many ’70s designs) looks less classic than bizarre now. Today, all of Fender’s mainstream models are variants of the Stratocaster, Telecaster, Precision Bass, and Jazz Bass, all designed more than 40 years ago. (Dirty N. has played a Strat since the theft, of course.)

I have a black 1990 Strat from Fender’s budget Squier division, but to anyone but a guitar geek, it is indistinguishable from the original 1954 model, or from the ones played by Buddy Holly, George Harrison, Jimi Hendrix, Pink Floyd’s David Gilmour, Ritchie Blackmore of Deep Purple, Stevie Ray Vaughan, Bonnie Raitt, and John Mayer. The country guitarists who inspired and helped Leo Fender create the Stratocaster could play my guitar, or a brand new Fender model, without a second thought. And a Strat-playing skate-punk shredder who came across a ’54 Strat could just as easily plug it in and go.

Leo Fender would have been puzzled, in 1954, to see people like me with the Stratocaster he knew plugged into an eMac, with all the amplifier effects and recording done digitally. But I think, after a few minutes, he would have understood.
Matchless and the boutique amp industry
[The Neurotics in 1994]

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The vintage guitar market includes keen interest in vintage amplifiers. You can spend thousands of dollars on an old Strat or Les Paul guitar that is not quite as well made as a cheaper, brand new one, and just as easily drop thousands more on a 40-year-old Fender, Marshall, or Vox amplifier that may sound great but can also be unreliable.

In the 1980s and ’90s (when modern amplifiers from the big manufacturers seemed particularly uninspiring), tone enthusiasts started taking the logical step of not just replicating those unreliable old designs from the ’50s, ’60s, and ’70s, but figuring out what was important: what made them sound so good. Then those people designed and built new amps that created similar great tones, but with much higher quality and more robust plans.

Sebastien, the guitarist in my band, has been playing one of the earliest successful “boutique” products, a Matchless DC-30 combo guitar amplifier, for more than 10 years (it’s on the left in this photo from 2002, and the one on this page, from 1994). It was extremely expensive when he bought it new—$4000 Cdn or so, worth more than any car any of us had back in those poor days—but the investment was worth it.

He’s never replaced the vaccum tubes that power the amp. The electrical cord connector had been wobbly for years before we finally had to replace the plug in 2004. The amp has been shipped to Australia and back. After that, it was stolen and then found a year later. These days, it travels from storage to show and back again, over and over, with no maintenance whatsoever. And it continues to sound absolutely amazing.

Here’s why it puts up with the abuse: Matchless amps are built like tanks, with the best possible components and classic, hand-wired designs. Other than the impossible-to-find and even more expensive Dumble amps used by the likes of Stevie Ray Vaughan and Carlos Santana, I’ve never heard a better tone or seen more rugged performance from a guitar rig. Many others agree.

In 2004, when we finally did have to make that minor plug repair, it was a problem that could be solved with a soldering iron, and a cheap replacement socket nicked from the back of an old computer tower. The technology behind the Matchless is decades old: it doesn’t even have any circuit boards in it, just tubes and components and wires and switches and such. Rugged, and easy to repair, even for a relative un-handyman like me, just like the guitar that plugs into it. There’s something to be said for keeping the ancient in some technology.

Since Matchless started in the late ’80s, many other boutique amp makers have emerged, including Dr. Z, Bad Cat (two former Matchless employees work there), Top Hat, and Komet. Even giants such as Fender and Marshall have created boutique divisions that hand-build both replicas of their sought-after old amps and new designs inspired by those tones. It’s a good market: although building boutique amps requires considerable labour and expertise, even cash-strapped guitarists will save up and spend ten times what a very similar factory-made amplifier costs, all for that elusive tone. […]

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Guitar Technology: Smash or Trash?

Misa Digital has built a unique kind of guitar, a Digital Guitar which has the guitar body with no strings and produces the “perfect sound”. It has 24 frets, a multi-functional touch pad and it ‘emulates’ the sound created from the guitar. That sound can be digitally morphed into any type of sound needed and different effects can be implemented even on each note. This means, it eliminates the use of external pedals and other effect system making the guitar playing experience more controlled and efficient.

It is not a modification of ac.ustic, electric or any type of guitar, but a new kind in it’s form which is expected to make a successful entry in the beautiful world of music. As of now, there is no news of when this guitar will be available in the market.

Do you like the idea of this guitar type? What are your thoughts? […]

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NAMM Archive

Basic Electric Guitar Circuits: Potentiometers and Tone Capacitors

What is a Potentiometer?
Potentiometers, or “pots” for short, consist of used for volume and sound control in electric guitars. They allow american to change the electrical resistance in a circuit at the turn of a knob.

It’s helpful to recognize the fundamental relationship between voltage, present and resistance known as Ohm’s Regulation when understanding how electric guitar circuits work. The electric guitar pickups present the voltage and current supply, whereas the potentiometers provide the resistance. From Ohm’s Legislation we are able to see how growing resistance decreases the circulate of present thru a circuit, whereas decreasing the resistance increases the present flow. If two circuit paths are provided from my frequent voltage supply, more present will flow thru the path of least resistance. […]

Guitar Pickups Single-Coil vs Humbucker
Tech Ed

Basic Electric Guitar Circuits | Guitar Pickups 101

Passive (i.e. battery-free) electric guitar circuits are relatively simple and the possibilities for customization are endless. A basic understanding of pickups, potentiometers, capacitors and switches is all you need to get creative and take more control of your instrument’s voice on an electronic level. […]

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Front Page Gear

JackTight Review: Guitar Repair Tool

The JackTight seems irrelevant for my situation. Though, one situation where it has a great benefit is when you have a jack that’s mounted to the guitar’s pickguard. Once this type of mounted jack falls through the pickguard, it becomes impossible to get to without taking the pickguard off. […]

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Musical Inventions We Could Live Without

you can argue with me that your Keytar is the best thing since sliced bread. Well, that’s where we disagree. A piano is made to be played like a piano, not a guitar. “Well, it was innovative.” Yeah…innovative in the complete wrong direction! A guitar is a guitar, and a keyboard is a keyboard. The sound a keytar makes is completely horrendous […]

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Live & Recording

STUDIO MONSTER – A Day At The Recording Studio

This being the fourth recording session as a band to date, we have a better grasp on how recording goes, and what speed bumps a band is always going to encounter almost every time. Problems happen, no matter how prepared you think you are to detour and prevent them, so you’ve got to be ready. […]

mesa boogie diy homebrew

DIY Homebrew Mesa Boogie Dual Recto

This kid built his own DIY homemade – Mesa Boogie Dual rectifier (2 channel). He says it’s created from old Tesla music 70 amplifier parts. You can see more photos here. Mesa Boogie Dual rectifier […]

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Acoustic Guitars

Recording with Taylor Electric Acoustic Guitars Techniques

Taylor acoustics have long been favored by artists and recording engineers for their clear, balanced tone. In fact, many engineers keep Taylors in their studios because they know they can always count on the clarity of “the Taylor sound” without the need for a lot of EQ tweaking. Between the crisp articulation and tonal balance of the bass, midrange and treble notes–full in the lower register, present in the midrange, and sparkling on the treble strings–Taylors offer a clean, even acoustic sound that makes recording a breeze. Taylors also fit nicely in a mix, occupying just the right amount of sonic space without taking up too much room or competing with other instruments. […]