On every instrument this is achieved in different ways. On a woodwind instrument, for example, the notes would all be played under one breath. On a violin they would be played on a single bow stroke. On the guitar legato is achieved by minimizing (or doing away with altogether) picking. This means using "hammer-ons" and "pull-offs," and when talking about guitar technique this is precisely what is meant by legato.
Legato technique can therefore be broken down into these two actions - when ascending using hammer-ons, and when descending using pull-offs. These two closely related techniques can easily be combined to produce smooth, flowing melodic lines, often played at quite impressive speeds.
Let's start off then by looking at hammer-ons. Hammer-ons are used to go from one note to a higher note on the same string without picking the new note. You play the first note by picking it, then to play the second note, rather than using the pick to make it sound, you "hammer-on" with your fretting finger. So for example, suppose you are playing the note E on the fifth fret of the B string with your first finger, and the next note you want to play is an F# two frets above. What you do is bring the tip of your third finger down, fast and hard, on to the string at the seventh fret to produce the note. You need to come down on the string perpendicular to the fretboard, and with enough force to produce the same volume, more or less, that you would with a pick. That's about all you need to know about hammer-ons.
When you want to descend to a lower note on the same string you need to use a pull-off. Many people think that a pull-off is simply a hammer-on in reverse, but there is slightly more to it than that, and this is where a lot of beginners go wrong. If you simply lift your finger off the string, in the opposite manner to a hammer-on, you won't produce adequate volume, or you may not get any sound at all. Your "pull-off" finger needs to really "pluck" the string, downwards towards the floor, in order to get the note to sound. So for example, if you play the note F# with your third finger on the seventh fret of the B string, and you then want to play the note E on the fifth fret of the same string, you firstly need to make sure that your first finger is already fretting that note on the fifth fret. Then you need to "pluck," or "pull-off" with your third finger in order to sound the note on the fifth fret. If you don't pluck enough you won't get enough volume, but if you pluck too much you can end up bending the note sharp, and it will sound horrible. You need to experiment a bit with this until you find the sweet spot.
So that's the two main techniques involved in playing legato on the guitar, but there are a couple more worth mentioning. The first is closely related to the "hammer-ons" we looked at above but doesn't involve picking a note first. This "hammer-on from nothing" technique lets you eliminate picking altogether when changing strings. Instead of picking the first note on a new string you simply hammer on with the fretting hand. This is slightly more difficult than a regular hammer-on as it requires a lot of power, accuracy, and good muting, but will give you an even smother sound, as nothing is picked.
The other technique is called "tapping." This takes the idea of hammer-ons and pull-offs and applies them to the picking hand as well. The "tapping" hand can use one or more fingers to 'tap' extra notes that the fretting hand can't reach, allowing you to play many more notes on one string for very fast scale runs, or lets you reach very wide intervals that you couldn't do with just one hand, great for playing very fast arpeggios as a smoother alternative to sweep picking.
So now that you are clear on the concept of legato playing let's take a look as some basic ways to go about practicing it. If we take the idea to its most basic application then we can start by just hammering on and pulling off between two notes. Alternating rapidly between two notes like this is called a trill, however to begin with we will be doing this very slowly. Fret a note with your first finger (any note) then hammer on to the next fret with your second finger. Make sure the note sounds clean and the volume is even. Now pull off back to the first finger, again paying close attention evenness and clarity of the note. Keep alternating back and forth between the two notes slowly to begin with (like a fire engine, or the "Jaws" theme). The aim here is firstly to ensure all the notes are clear and even, with no unwanted noise, and secondly to build up your finger strength and endurance. Try to do this exercise continuously for at least five minutes without stopping, and use a metronome to keep your timing in check.
Once you've done this you next need to try the same exercise with all possible finger combinations. You've done fingers one and two, so now try one and three. Play a note (any note) with the first finger, then hammer on two frets above with the third finger. Trill between these two notes for at least five minutes. Then try fingers one and four. Then two and three, two and four, and finally three and four. You'll find that some finger combinations are more difficult than others, especially the third and fourth fingers, so you should spend more time working on these.
The next step after you have got to grips with two note trills is to start practicing three note patterns. Keeping one finger per fret you should experiment with finger patterns using fingers 1 2 4, 1 3 4, and the stretch fingering 1 2 (or 3) 4 with a fret in between each finger (for example first finger on the fifth fret, second on the seventh, and fourth on the ninth). Patterns you can try include 1-4-2-4, 4-1-2-4-2-1, and 1-2-1-4. Do these with all three finger options mentioned above, and practice them on a single string, then on multiple strings. Try moving up and down the fretboard as you play them. Then, once you can play them comfortably like this you cans start applying them diatonically to the three note per string scale shapes. This is where they turn from unmusical exercises into usable musical ideas.
By now I hope you get the idea of this. To take things further you can start trying more complex patterns, involving four, or more, notes. Mix patterns together, try skipping strings. Add right hand tapping into the mix. The possibilities are endless, so have fun with it.
Before I finish this article I want to look at some of the more common technical problems that people have when they first try this. The main issue is that of finger strength and endurance. It takes a lot of stamina to play continuously using only the left hand, especially at high speeds, and this is not something that can be developed over night. It takes time. Practice regularly, and don't overdo it. In time you'll see progress, and find it becomes much less physically demanding on your hand. Legato playing can also be quite rough on your fingertips - more so than normal picking. Again, there's nothing much you can do about this, just keep practicing and your fingers will toughen up and it will no longer be an issue.
When practicing legato I always recommend using a fairy clean amp setting. Distortion can hide a lot of mistakes and especially covers up inconsistencies in dynamics. Using a clean sound will help you hear how evenly and cleanly you are playing, and this should be your main goal. From time to time though it can be a good idea to crank up the gain, just to check you're not producing any unwanted string noise, so pay attention to good muting.
As with all practice you should start off slowly. As your finger strength and stamina increase you can increase the speed, but always pay attention to accuracy. Don't just chase speed - speed comes as a by-product of accuracy and stamina. Try to pay the most attention to fingers that are weaker until you can play equally well with all fingers, as this will make things much easier in the long run.
So that concludes this overview of legato technique. Hopefully it has given you an insight into what this playing style can offer you as a guitarist - the ability to play fast, flowing, melodic lines with a sound that you just can't get from picking every note. I also hope that I've given you some ideas about how to learn, practice, and apply this technique, so get practicing and start incorporating legato into your own playing.
About the Author:
This article was written by Chris Lake, a professional guitarist and guitar teacher of over 25 years. If you would like more help with all aspects of learning the guitar may I suggest you head over to Chris's website where you can get a free copy of his latest eBook about playing the guitar - The-Guitar-Guide.com.