I want to arrange a song for fingerstyle guitar. it starts with four chords arrpegiated: Bm,Em,G,F#.and while those chords are played by a guitar, another guitar start playing a solo around the 7th and 5th frets. so the question is how can I combine the solo with the chord sequence. Should I find the notes of the solo near the chord or what. this is my first arranging attempt so I might be missing something.
I found this YouTube channel (Michael New) really insightful in terms of composing with chord progression:
Summary of video:
When defining notes of a melody for a chord progression, there are some guidelines that you can use. You can choose to use core tones or a non-core tone. A core tone is a note that belongs in the chord that is being played (for example, the note C is a core tone of C-Major). Core tones, fit very well and it doesn't give any tension, because the notes are already in the chord. Whereas, non-core tones are notes that are not in the chord that is being played, and they give tension or dissonance. Composing revolves around creating and dissolving of tension in order to create an emotional response.
First I want to say that I played the chord progression (Bm,Em,G,F#) and it sounds really interesting. I like it - especially arpeggiated as you suggest.
I am going to say those chords fit into the key of B Harmonic Minor (which is different than B Natural Minor). B Harmonic Minor contains the following scale notes B C# D E F# G A#.
The first guideline to help choose notes for your solo to be played over the chords might be to choose most notes from the scale (B C# D E F# G A#). The next guideline is to emphasize the notes that are chord tones (meaning one of the notes that form the chord) in each phrase of your solo played over a given chord. It is usually a safe bet (though not required) when you start the phrase of the solo with the root note of the chord being played or at least with one of the chord tones. Your solo notes will be more likely to seem to go with the chord if you include more chord tones in the phrase than non chord tones.
For your choice of non chord tones to blend in to your solo phrase, try choosing from the notes that are both in the primary key and also in the key that corresponds to the root of the chord you are playing. For example, when you are playing the E minor chord, we know that all the chord tones belong to the key of B Harmonic Minor. The Em chord contains the notes E, G, and B - all in the key of B Harmonic Minor. The notes that form the E minor scale are E, F#, G, A, B, C, and D. The B Harmonic Minor scale notes again are (B C# D E F# G A#). So the notes common to both scales other than the three chord tones of E, G and B are F# and D. So it would be safe to include those notes while soloing over the Em chord. So now we have E - F# - G - B and D as good candidates for notes that will blend well with the Em chord (chord tones highlighted) and stay within the key of the song.
The notes you play can be in any octave and may sound more interesting if you vary where you play each note or which octave you play it in with each pass through the chord progression. In other words, you might start out playing the notes in the same octave as the notes of the underlying chord but next time through play the same notes an octave or two higher to provide a sense of movement and give the solo more interest.
Of course in music there are no rules other than, if it sounds good it is good! So use the ideas presented above as a guideline to get you in a safe ballpark, but don't be afraid to allow your ear to be your ultimate guide in choosing what sounds good.
Have fun with your arranging and composing.