Vibrato
Vibrato is a simple concept but a difficult technique to master. It involves moving the pitch of a note up and down repeatedly, to give a sustained note a bit more emphasis or liveliness. The actual pitch of the note is in constant motion, moving up and down but never staying absolutely still.
Vibrato is commonly written in tab by the tilde character: ~. Sometimes vibrato is indicated by a v, but more commonly you will see several v's or a series of /'s and \'s which means wide vibrato.
--5~~-5v-------5vvvvv5/\/\/\/\/\-----5----~~~~~~~
The first two notes are given normal vibrato, whereas the second 2 have wide vibrato. The last note implies delayed vibrato, where the note is first sustained without vibrato for some time.
Contents
PreReqs
Common Methods
Bending
The most common way this is performed is by doing very small bends (see Bending. The same way you do a quarter bend, you start your vibrato. While bending is typically designed to reach a certain pitch (and possibly return to the original), vibrato only wants a small deviation from the original pitch but to start to return to the original pitch as soon as the peak of that deviation is reached. And when the pitch is back to the original, you start to bend up again.
Note that with this technique, you can only go above the original pitch, not above and below. The average pitch of the vibrato is actually above the original note.
One thing to watch out for is that you only bending in one direction. IE, you are always pushing the string away from its natural fretted position, or you are always pulling it. If you push up, then don't simply allow the string to return to its natural position but "pull through" that point and begin bending higher in pitch using a pulling technique, there is an artificial sound to the transition. Picture a sine wave - the high and low peaks are rounded off and smooth. When you "pull through", you don't smoothly approach the low peak but blaze through it. This would be like if the sine wave had pointy peaks on the bottom but rounded peaks on top, like a bouncing ball.
Finger Vibrato
Finger vibrato bends and straightens the fretting finger(s) to bend and release the string. It has a similar motion to pulling a trigger.
Wrist Vibrato
Wrist vibrato rotates the wrist using the index finger knuckle or thumb as a pivot point to bend and release the strings.
Arm Vibrato
Arm vibrato moves the entire forearm at the elbow to move the position of the hand as it holds the neck. This is generally not recommended.
Pushing/Pulling
Where bending is vertical motion, pushing/pulling is horizontal motion. Without actually moving your finger's position on the string, you move your hand towards and away from the bridge. The friction of your finger against the string is actually strong enough to slightly push and pull the string towards and away from the bridge, decreasing and increasing (respectively) the tension on the resonating part of the string.
This technique is difficult to master - it feels like you are going to slide off the fret. In this regard, it's very difficult to get a wide/large vibrato from this technique.
The main benefit to this technique is that you are not simply changing the pitch above the original note but above and below it. Thus, the average pitch of the vibrato and original note should be very close. Also, it is possible to apply this technique to chords.
Vai's Circle Vibrato
Steve Vai decided using just one of the above techniques was not enough, so he developed a "circle vibrato" technique that combines them both. It's basically a 4-motion vibrato; however, each motion blends into the next one to keep it sounding smooth.
- push the string towards the bridge, lowering the pitch
- bend the string slightly, while continuing to push the string towards the bridge, raising the pitch to the original pitch or slightly above
- pull the string away from the bridge, raising the pitch
- release the bend, while continuing to pull the string, so the pitch is slightly above the original pitch
You'll notice you end up making something like a circular motion, hence "circle vibrato". You can swap the push for the pull in the steps above so you are making a counter-clockwise circle vs. clockwise, if that's more comfortable - the overall effect is unchanged.
So what's the benefit? You get the best aspects of both - the average pitch is closer to the original pitch than if just using bending, but you can get a bigger/wider vibrato than just using pushing/pulling. You can also purposefully reduce the smoothness of the transitions above, which can give a strange yet appealing sound to the vibrato in some cases. The downside is that this technique takes some serious practicing to get it to sound natural and smooth. It's also difficult to perform with the same speed as the other techniques. And speed is really a crucial part of the vibrato, to make it sound like a unified effect instead of a series of pitch shifts.
I don't know of any player besides Vai that uses this technique. I think it's worth learning for the sheer versatility, but I wouldn't worry about mastering it unless you find something really appealing to its sound.
Whammy Bar
The whammy bar is the easiest and most versatile way to get a good vibrato. You can make it extremely large/wide. It's easier to apply to bends. You can apply it to chords, which is basically impossible for the above techniques. You can even continue the vibrato as you change notes on your left hand. And you can shift the pitch above and below the original note, so the average pitch matches the original.
The only real downside is that it is difficult to use the pick and whammy bar at the same time. And if you're not already holding the bar, transitioning from picking to grabbing the bar can be slightly too time-consuming to work into a quick passage.
If your bridge is a dive-only model (typical on a Fender Stratocaster and clones), then what you have to do to get the pitch to average around the original pitch is bend the note on the fretboard higher as you apply vibrato. The amount you should bend the note will depend on how wide of a vibrato you are applying with the bar.
The whammy bar can be very sensitive. For a vibrato technique, I like to grip the bar loosely between the 1st and 3rd digits of my right-hand ring and pinky fingers. Then I make a slapping motion, like I'm swinging a tennis racket back and forth. This is a lot of movement in the hand, but most of the movement is around my index finger knuckle. The ring and pinky fingers only have a slight movement. The momentum of the swinging motion guarantees a smooth vibrato movement. How tightly I grip the bar and how forceful my swinging motion are determine the width of the vibrato. Note: this only works for a floating bridge. For a dive-only bridge, you'll have to push on the bar, going from strong to lighter pressure - you don't want to fully release pressure against the bar, or the bridge will slam into the body; and you won't get a smooth vibrato. But getting it to be subtle will take work.
I would focus on getting the vibrato smooth first, then work on the appropriate width. Try to consistently be able to get different widths for your vibrato.
Good Technique
Transition
The main difficulty in getting a good sounding vibrato are the transitions where the pitch shifting changes directions. The pitch shift should follow a sine wave pattern, slowing as approaching and leaving both its high and low peaks. This prevents the transitions from catching the listener's attention, as opposed to the general effect of the technique.
The best way to work on this is to practice slowly. If you try to get there too fast, you end up developing a habit of simply wiggling without real control with bad transitions and no control over speed. Start painfully slow, so it sounds like some awkward out-of-tune bending. You want to focus on always keeping the pitch moving up or down smoothly with special attention to where the pitch shift switches directions. It may help to use a wider vibrato than you actually want to use when starting to practice.
Assuming you are using the bending technique, I find it's easier to use your wrist more than your fingers for the string bending. Instead of straightening or bending your fingers to move the string up and down on the fret, you simply rotate your wrist one direction than the other. With the area between your index finger knuckle and thumb pressed against the side of the fretboard, this gives you a fullcrum to pivot the wrist against. You'll notice as you rotate your wrist, your fingers move in a partial circle around that pivot point. You can basically lock your fretting finger in place and just let it focus on keeping the string fretted cleanly. Let your wrist motion push/pull the string up/down the fret. It can feel awkward at first, but it's actually easier IMO.
I also find bending the string by pulling it towards the floor (vs. pushing it towards the sky) is easier to control and get a smooth transition, particularly for the wrist motion described above.
Width
Width refers to how far the peak frequencies deviate from the original pitch. A wide vibrato has a large deviation.
If the vibrato is too narrow, it's hard to tell it's even there. There may some cases where this is desirable, but for the most part why bother? If the vibrato is too wide, it will sound chaotic, deviating too far removed from the original pitch. In other words, the vibrato will become its own point of interest, rather than simply embellishing the original note.
Again, practice slowly, trying to peak at around a 1/4 bend. If your vibrato is too wide, try practicing making it as narrow as possible while still having smooth transitions. If it's too subtle, do the opposite. Basically, cage yourself in your weak areas - you are not free to leave until you have defeated the challenge.
Speed
When you employ vibrato, you are creating a repeating cycle. Let's assume any cycle starts at the lowest frequency, rising in pitch to the highest frequency and descending back to the lowest. What is the correct vibrato speed? This will depend on the context of the note in the piece. In general, however, I find about 2-5 cycles per second is a good speed. Slower than this and it sounds like the pitch is being bent in one direction then another, as though you are trying to hit certain notes via bending, rather than embellishing the sustained note. Faster than this and you start to lose the vibrato effect - it sounds like the note is buzzing or just going crazy.
Generally, it's difficult to play vibrato either so fast or so slow that it simply sounds horrible. But that's no reason to shirk on our training. You should practice using faster and slower speeds and determine what you feel sounds best. The important thing is to always maintain control, keeping smooth transitions and appropriate width. I found that my ideal vibrato is a little slower than the natural inclination of how my left-hand wanted to play it. So I had to work on reducing my speed.
A common beginner mistake is to shake the left hand instead of using a good bending technique. This will usually make the vibrato too fast, as well as weak. Be sure to apply the proper bending techniques described above. Also, fretting a note with multiple fingers (if fretting with the ring finger, also fret the 2 frets behind it with the index and middle fingers) can help get better control over the vibrato and slow it down to a nice speed.
Speed is often tied to the tempo and feel of a song. For a soft, sweet, singing lead, my vibrato is going to be a little slower. But for a fast, rockin', shred solo, I may want to use a faster vibrato.
In-Time
A good way to gauge speed is to try to play your vibrato in-time with the beat. Playing each cycle to an 8th note or 8th note triplet often works very well.
When and How Long?
When should you begin to put vibrato on a sustained note? This depends on the context of the note, and how long the note's duration is.
If a note is part of a fast passage of notes and the vibrato is there to emphasize it, you likely want to employ the vibrato almost immediately after sounding the note. If the note is a longer, sustained note at the end of a phrase or part of a slower melody, you may want to wait a little while before starting to give it vibrato. You want to let it sound without any flair to really lock your mind onto that pitch, but use the vibrato to keep it sounding alive. It's like watching a person as they fade into the distance - it's more lively and attention-grabbing if they are waving than simply staring at you.
Practice both ways - start vibrato immediately vs. wait a little while. Also, for delayed vibrato, it sounds best to gradually increase the width up to a certain point. This gives you a nice smooth transition into the vibrato, so it sounds like the note naturally fell into it, rather than completely and suddenly shifting from static-pitch mode to vibrato mode.
You can sustain a note longer with vibrato - it naturally transfers energy into the string. This doesn't mean you should try to extend it indefinitely. As the note gets weaker, you can start to hear the noise associated with bending the string up and down the fret. This is a good reason to use the whammy bar for any notes that need to sustain with vibrato into silence. Or as you sustain with bending vibrato, use your right hand to roll down the volume knob on the guitar, so the note fades out more gracefully. Or slide down and mute the string. Usually you can let delay or reverb effects provide a nice natural decay to the note.
Why Vibrato?
Vibrato is mostly useful to emphasize a certain note. This is helpful where the guitar tone or piece covers up emphasis via picking dynamics. It also helps draw emphasis to a sustained note. A strong pick stroke will only emphasize the attack of the note. For a long, sustained note, this is a very minute portion of the note's lifetime. Vibrato does a much stronger job of keeping the listener's focus until the note is almost completely decayed.
It's nearly impossible to get an instrument perfectly in tune. Vibrato helps gloss over the small pitch differences between instruments or different takes. Rather than trying to sound an exact frequency, vibrato is covering a small range that is likely to contain the ideal pitch.
Other Techniques
Fade in
Since vibrato can be used to transfer energy to the string, it makes for an interesting way to fade-in a note from silence. Think Jimi Hendrix 's "Foxy Lady". It can be a little noisy, so if you want something more subtle, it's best to use a volume pedal or the guitar's volume knob.
Ultra-Wide Vibrato
Sometimes an ultra-wide vibrato can be used to give an out-of-control feeling. For this, the actual note is less important than the effect. This is useful in a solo where there's lots of bending, sliding, fast-playing, and/or unusual scales being used.
Rough Transition Vibrato
If you read about the good technique section above, you'll know that the key to a natural-sounding vibrato is smooth transitioning from where the pitch hits the extremes. This breaks those rules down in favor of creating an eyebrow-raising WTF moment.
My personal favorite is "through-zero" bending. So as mentioned, you can either bend upwards or downwards; but when doing vibrato, you should only bend in one direction to prevent going "through zero" which will screw up the transitions around the lower pitch extreme. Well, I break that rule here. If done with a wide enough vibrato and enough speed, it sounds like some kind of crazy synthesizer automation.