I wondered if its possible to play those fast single line melodies and solos with your fingers (on an acoustic). I have been playing fingerstyle for some time now, and I have never encountered fast single line melodies, but think of it like this: If I have no pick at hand, and would like to play fast solos, how can that be done? Is there a specific technique for this? Can you do it without fingernails (I dont use finger nails, since I would have to grow them very very very long in order for the tip of the nails to be over the fingers)? Can it be done NOT using a classical position?

But boys will be boys and girls have those eyes
that'll cut you to ribbons, sometimes
and all you can do is just wait by the moon
and bleed if it's what she says you ought to do
I'm aware of several techniques for playing fast, single-note runs with the fingers.
1. The standard classical-type lines played with either three fingers or the thumb and fingers all sequentially plucking the same string.
You can hear this on many classical guitar pieces; well-done it sounds almost like a tremolo line.
Thumb and one finger alternating up-and-down strokes. This is pretty much what Chet Atkins used to do; he admitted that the classical method was perhaps better and regretted not having learned it.
Using the thumbnail as a flatpick. Marcel Dadi (French fingerstylist) used to do this; you just hold the thumb and forefinger together as if you were holding a pick, and use the edge of the thumbnail to strike the strings.
There are probably others.....
look at some bass players. Some can do amazing stuff fingerstyle.
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Gibson Les Paul Studio
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Quote by Geldin
Junior's usually at least a little terse, but he knows his stuff. I've always read his posts in a grouchy grandfather voice, a grouchy grandfather with a huge stiffy for alternate picking.
Besides that, he's right this time. As usual.