Playing guitar well lives and dies in the trench of your tone.
Capturing the right sound is more than adjusting the knobs on your amp, though. Good tone requires that you be thoughtful about everything that has to do with making sound on your instrument: technique, amps, settings, guitars, pick-up selections, the weather, your mood, etc.
Watch these two videos featuring live performances by famous people, and see if you can tell who did their tone homework:
http://www.youtube.com/watch?v=lfXL7m2889k
http://www.youtube.com/watch?v=_fgbJwdrSyQ
Pretty obvious, huh?
The rest of this post outlines the details and strategies for getting David Gilmore-like tone and avoiding Skid Row-like tone.
Timbre
Timbre, also known as tone color or tone quality, is comprised of two contributing factors: the sound envelope and the overtone series.
The sound envelope outlines how a sound is produced and how it’s sustained. An envelope is like a sound’s life story told through its shape. The concept is probably familiar to you if you’ve done any wave editing in an audio program like Cubase or Pro Tools. Here’s a bass guitar’s envelope as displayed in Cubase:

Notice the way it sustains and decays in one long decrescendo at the end–one of the hallmarks of a plucked string instrument.
For comparison, check out the envelope of a kick drum:

It’s nothing but transients–the attack, sustain, and decay are all happening in quick succession.
In addition to the sound envelope, the overtone series contributes to timbre. The overtone series, sometimes called the harmonic series, is a phenomenon of sound whereby a fundamental pitch (frequency) begets other, sympathetically generated, sounds which exist within mathematical ratios of the original sound.
What the hell does that mean?
I’ll tell you what it means, it means that all sounds that are naturally generated are, in fact, complex sounds consisting of a principal pitch and many subordinate quotient pitches.
Dude, you’re not helping.
Okay, try this: Inside all sounds are other sounds. Those other sounds are called overtones. In music, the other sounds occur in a fixed and specific order known as the overtone series.
Cool? If not, watch this.
All musical tones are complex sounds containing overtones. Even your voice box generates overtones. These overtones are important to the overall character of a sound or pitch. In order to get a pure fundamental pitch, one without overtones, we must turn to science. Here is a video of a sine wave (a pure tone generated by oscilloscope) with the overtones added one by one.
So what does all this have to do with tone?
Well, timbre—that combination of the sound envelope and overtone series–is determined by how an instrument or voice produces and sustains its sound. A tuba and a bass guitar, for example, produce and sustain their sounds differently from one another; and so, have different shapes to their sound envelopes and a different intensity to their overtone series.
A tuba player produces and sustains his or her sound by buzzing their lips into a mouthpiece and simultaneously blowing down a length of tubing. A bass guitar player, on the other hand, produces and sustains his or her sound by plucking, with the fingers, a length of string. These two procedures will stimulate the overtone series differently and also produce different sound envelopes. Your brain, through the mechanism of your hearing, can tell the difference between the two instruments, even if the tuba and the bass guitar play the same exact note.
Your tone, therefore, is a function of your sound’s envelope and your sound’s overtone series.
Dude, I thought we were going to be learning about adjusting amps.
Okay, okay—we’re getting there. Let’s move on.
Sound Frequency Spectrum
Humans hear between 20 hertz and 20,000 hertz. Hertz measure the number of times a sound vibration completes its cycle–back and forth–in one second. This means that if a sound is 50 hertz, than it literally vibrates back and forth 50 times in one second.
Think of your guitar strings when you pluck them. You can actually see them vibrating before your eyes. If you watch the vibrations as you play your high E-string, then you’re seeing your string cycle back and forth 330 time per second. Your E-string, therefore, sounds at 330 hertz.
Okay, so, now that we understand frequency, let’s return to the sound frequency spectrum. We usually engage with the range of human hearing via an equalizer and think of its regions in terms of bass, middle, and treble. Take a look at this equalizer from Cubase:

Notice, along the X axis, that the sound frequency spectrum is labelled from 20 hertz (Hz) to 20 kilohertz (kHz). Notice also that I put a boost at 500 Hz and a cut at 2 kHz. These maneuvers will increase and decrease the volume respectively at those selected frequencies. This is the primary function of an EQ—to boost or cut selected frequencies.
Low sounds on the sound frequency spectrum, like a bass guitar, tuba, or bassoon, sound low to us. High sounds, like a flute, ukulele, or oboe, sound high to us. Mid-range sounds like a guitar, piano or mandolin, sound right in the middle. For convenience, sound engineers divide the spectrum up like this: 20-80 Hz is low bass, 80-320 Hz is upper bass, 320-2,560 Hz is low mids, 2,560-5,120 Hz is upper mids and 5,120-20,000 Hz is treble.
Your guitar (and many other instruments) have sound over a wide swath of the sound frequency spectrum. Here are the frequencies of your strings:
- High-E=330 Hz
- B=247 Hz
- G=196 Hz
- D=147 Hz
- A=110 Hz
- Low-E=82 Hz
Of course, when you bring fretted notes into the fold, you’ve got a much broader range on your guitar than just the open string frequencies. In fact, the range of the guitar is about 82-1,046 Hz.
Remember, though, all notes beget other notes in the overtone series. So, even though you’re playing your high-E string at 330 Hz, you’ve got action happening all the way into the upper mid-range and the treble. Any adjustment you make to your equalizer should take this into consideration.
Okay, there’s one more thing concerning the sound frequency spectrum that we need to talk about: the equal loudness principal. The equal loudness principal describes the unequal way that humans hear. Stated simply, we are more sensitive to sounds in the mid-range than we are to sounds in the bass or in the treble range.
Dang, dude, why didn’t they call it the unequal loudness principal?
Good point. I admit, this shit is confusing.
So, if two different frequencies are sounding at the same intensity but one is at 900 Hz and the other is at 10,000 Hz, we’ll perceive the one at 900 as being louder.
This is true. I am not making it up.
If you think about it, all the important things sound in the mid-range, including the most important thing: our voices. That’s right, natural selection and Darwin strike again. We evolved to favor the mid-range so that we could more effectively communicate with one another. Deal with it bass players.
So, guitar players, pretend I am shouting this next thing from a mountain top:
BECAUSE OF THE EQUAL LOUDNESS PRINCIPAL YOU MUST DIG INTO YOUR BASS STRINGS AND FINESSE YOUR TREBLE STRINGS TO ACHIEVE A BALANCED SOUND.
Now and forever, every time you play guitar, you must do this.
Have you ever sat and listened to a beginner guitar player? I mean really listened and wondered, “why do they sound so god damned bad?”
Twangity twang twang, bad news, twang twang.
It’s because of the equal loudness principal–get a handle on it newbies.
Strategy
Okay, so how do you use all this information to sound good?
Well, your timbre, including all the details of your envelope, overtone series, and sound frequency spectrum, lives and dies with your plucking or picking technique. Even before you plug into an amplifier or adjust your EQ, you need to carefully consider the tip of your pic or the tip of your finger.
Here is a simple heuristic: the more surface you use to strike your string, the more robust your tone will be.
This means that a nice round, thick pic or a carefully placed and activated finger with a full, rounded nail will stimulate more pleasing harmonics out of your guitar than a thin, sharp pic or a calloused finger tip without a nail. Look at these pics:

The jazz I, on the far right, will sound better every time. It’s harder to play fast with, and it may take some getting used to, but this pic produces a superior sound to all others. The rounded tip simply puts more surface on the string.
Check out this close up of a classical guitarist’s hand sounding the strings:

Notice that the nails are shaped a lot like the Dunlop Jazz I pics. Have you ever listened to a classical guitarist and thought, “I just love that sound. It’s like a magic box, I could sit and listen to it all day.” Well, that opinion, and the maniacal quest for a round, beautiful tone displayed by most classical players, is related.
Get as much surface behind your strings as possible before sounding them. Throw your thin, sharp pics in the garbage can. Start using your nails and/or a rounded pic.
You’ll sound better, I guarantee you.
Another string sounding consideration is where along the string to pluck. If you play down by the bridge, you’re naturally going to get a thin, bright sound. If you play up the neck, you’ll hear your sound fill out and become round and hollow. Considerations about where to pick are made moment to moment but you should always know how a musical passage should sound: Comping rhythm changes for a bright accompaniment? Play close to the bridge. Trying to get your melodies to sing like an aria? Play up the neck.
Try it.
Okay, the last consideration for tone (that I have left in me) is your guitar amp. You may be disappointed to hear, but you should keep your bass, mid, and treble flat. Rely instead on your picking technique, your pick-up selection, and your guitar choice to manipulate your tone. As long as you have a tube amp and a half way decent guitar, you should be cool with the flat EQ maneuver. Of course, like so much else in the musical world, amp settings are a matter of personal taste. Experimentation is the the key.
In addition to all this technical stuff, something as simple as developing a vocabulary for musical sounds can help the quest for tone. Is the sound coming from your amp harsh or is it warm? Does your acoustic sound rich or does it sound dull? No matter what words we use to describe tone, most of us are pretty good at telling the difference between what sounds good and what doesn’t.
Most of all, when considering your tone, just listen to yourself and use your ear to get that fat, warm sound we all desire.
I enjoyed your thourough look into to the fundamental elements of tone.
I must make one critique as you hit a pet peeve of mine.
For all of the intensive detail and exposition in this article, you made a fundamental error at the outset with the comparison videos. It is misleading to present for conparison such divergent recording qualities. The first is a modern, high-quality recording taken directly from the board. The second is a terrible VHS dub of a show recorded from external mics. That fundamental disparity will always favor the better recording as the tone of the recording is better. The poor recording couldn’t compete no matter the guitarist’s tone.
I take such issue with this b/c the public will invariably side with a higher quality recording regardless of the quality of the performance.
I think a better comparison would seek to downplay as many of the differences in recording as possible.
One notable example of bad tone would be Vernon Reed from Living Colour. Love his playing. Hate his tone!