I need to mention two other things I forgot.
There are many more techniques besides legato and alternate picking. I don't know why that thought didn't hit me when I wrote that reply. But anyway, always think about what you could be doing to make notes more expressive - slides, pinch harmonics, grace-note articulations, bends, and of course the whammy bar!
For inspiration on this subject, check out the melody to Satch's "Surfing with the Alien." He does something to every note, whether it is subtle vibrato, a quarter bend, a slide, a full bend... There is no "plain" note to be heard.
In my other response I only touched on the articulation aspect of phrasing, but there is another equally important aspect: rhythm.
Sixteenth note rhythms/six 16th note groups all over the neck sound repetitive and boring - especially when combined with scales played in sequences, up or down, whatever. I'm not a Petrucci basher (as I may come across) - I think he's a fantastic guitarist - it just happens that I don't prefer many of his stylistic techniques.
Again, the human aspect is here for a real-world example: people talk in a rhythm, but it's not a regular one at all. If you listen to Zappa, he's said that human speech is the inspiration for his insane, harder-to-follow rhythms (e.g., Black Page #1). Now obviously if you attempt to improvise like Zappa composed, you'll sound like a Zappa clone so I advise against it. Try experimenting with different combinations of rhythms.
How about a 16th note triplet followed by four 32nd notes, then a heavily articulated eighth note, a 32nd note quintuplet, a quarter-note trill and lastly a sixteenth note septuplet to finish off the measure. Played with a combination of legato and alternate picking, plus other expressive techniques, and large melodic leaps at a leisurely 90 bpm. Now that's some tasty killer phrasing!
And besides talking in irregular rhythms, we accent certain words, and change the tone of our voice sometimes to express ourselves. With a little bit of time and some experimentation (which I highly encourage) this is actually easily translated to and recreated on the guitar.
In addition to that we pause at commas, periods, colons, and semicolons - that's what rests are for! As above, this is obviously easily recreated on the guitar (just stop playing!) but like everything else requires practice to be used most effectively.
Sounding truly human is a real goal, and it's something that would be interesting to make as a part of your practice routine. A paragraph [edit: on the guitar] a day keeps the bad phrasing away! (lol sorry if that sounds cheesy but hey my brain is fried - I'm about to go to bed!)
Check out this
awesome Vai article on polyrythms, metric modultion, and transcribing the human voice.
Hope my little 'column' (I sure write enough!) on rhythm in phrasing helped/inspired you.
(Edited by sixstringphoenix at 7:00 am on Aug. 10, 2001)