I have played classical guitar for many years, but my training has been all about playing pieces, and no improvisation was included; everything just technical, and I am in a very good state in it. Recently I have started to play electric guitar and am trying to learn to improvise. Man it has been a tough path! I have learned pentatonic scales, the patterns, have learned many of the basic chords, and I have grasped the fundamentals of scales over chord progressions, but when I play a chord progression and start to play with it, I can only play very simple and boring stuff. I can't make any nice phrases. What do I lack? What should I learn next? Thanks.
If you haven't already, I would start by learning the 7 modes on guitar. Ionian, dorian, etc. They can be found here.
This is where I started and I'm by no means an expert at improvising, but once I further understood when to use which mode when soloing over certain keys it definitely helped my ability to improvise on the spot.
This next part is going to require a basic understanding of music theory. Modes can be kind of confusing at first, because in any given key (for example C), all the modes play the same notes but just start and end on different notes. Ie D Dorian would be played D,E,F,G,A,B,C,D. The usefulness of this is best shown when soloing/improvising over certain chords. For example, if you are improvising over a C chord and you're playing C Ionian (which is just C Major) you're going to notice certain notes sound weak, certain notes sound strong and certain notes a little tense. This is because of the notes within the C chord clashing with the soloed notes. Ie the
E in the C chord does not play nice with
F when soloing, and D may sound tense. Practicing this will show you much more than me telling you. However, if you're playing over a G chord, and you're playing G mixolydian, different notes are going to feel tense, strong or weak. Now the
F that we were playing over C Ionian that sounded kind of weak, sounds great when playing over a G chord. The quality of the notes change as you change the chord you're improvising over.
In an attempt to summarize that paragraph, modes will help you understand the relationship between the notes you're soloing and the chords you're playing over.
Another tip that may help:
I've always found that I always want to go back to my "default" solo scales and riffs. Forcing yourself to break out of this by using a different scale, mode, etc or changing the timing I found helped with improvisation.
I would suggest copying solos or even just phrases from those people that you admire. Each musical genre is its own language. Even if you know the grammar you still need to practice speaking the phrases. Then you can start to deviate from the learned solo or phrases or embellish it or mix and match phrases from different influences.
Also you can try learning different patterns in a scale. Instead of up and down the pattern try up all the way in thirds or fourths or fifths etc. You could even incorporate classical music phrases into improve with a more modern.
Try learning a pattern to really quick chord changes to challenge your theory technique and then try jamming for 20 minutes on a one chord vamp to challenge your melodic sense.