Vibrato is a technique where the smallest thing can make the biggest of difference. Playing with vibrato is not necessarily hard or will impress anybody but it really will give you more of a vocal, soulful and professional sound.
Vibrato is when you bend the string just slightly back and forth causing the pitch to raise just slightly and then back down constantly over and over again. The end result gives your playing more of a vocal and expressive quality and your note will also sound longer. Take the following example.
Vibrato is not usually notated in tab. This is because playing with usually up to the players discretion. In some cases where vibrato has to be notated, it is either done with a 'v' above the tab or with a series of '~'.
To play the above example, first play the 5th fret on the high e string. Then you want to cradle or rock your fretting hand back and forth to bend the string just slightly. Actually bending your string as taught in our lesson on bending is not the goal. You do not want to bend the string enough so it sounds like a different note. Instead you want it to sound like the same note, just altering the note just enough to give it some vibrato.
Again vibrato is not a cool or flashy technique but it adds such a huge difference to your sound. It will give you a more vocal, soulful, expressive and professional feel to your playing. Not only that but it also helps in making note sounds longer. If you have a long note you holding on to vibrato will help in sustaining that note longer. Without vibrato the note will decrease in volume faster.
In the classical tradition the above method is incorrect. A classical player, instead of cradling the string up and down, would cradle the string from side to side. Using the finger that you fretted with, wobble it back and forth. In effect, your increasing the tension and then decreasing the tension on the string by pulling on it. Watch a classical guitarist, violin player or any other type of stringed instrument. To produce vibrato they do not bend the string but instead wobble their finger.
The classical technique produces a more proper vibrato. The problem with the rock/pop technique is that it can only increase in pitch from the original note. With the classical technique, not only can you increase in pitch but you can also decrease in pitch. This is not to say you shouldn’t use the rock/pop technique as it works and there is nothing wrong with using it. But the classical technique does produce a more vocal like vibrato.