#1
Hey guys.
What do you do when you're jamming along to a song, and you want to work out the lead guitar parts, but you can't find the scale you should be playing in. Generally, its easy enough. But I was doing it with BB King's One Kind Favour album, which is very piano/horns, and his lead guitar appears to meander up the fretboard a lot, which means I can't use my standby tricks:
Play random licks until one seems to fit
Try and decipher the bassline

So what else can you do?
#2
Use my ears, ****ing around with pentatonics or just play notes that fit, then you will notice what key you're in. For example when you notice you only use natural notes and everything sounds major, you could just be in C major!
#3
You need to find where the song resolves. That is the only definitive, reliable method. Give me a second and I'll find another one of these threads I've posted explanations in.

Edit:

Quote by Eastwinn
The above are good methods, sure, but there is a more reliable method. The key of a song (not necessarily related to the key signature, but normally is) is where the root of the scale is. If you're in G major, it's a major scale whose root is G. If you're in Db minor, it's a minor scale whose root is Db. That's what a key really is.

The root note of a scale has more significance than most newcomers are led to believe. It's not just the note that scale is based off of, it's where the scale resolves. Always. Resolution is a determining factor. If it resolves somewhere else than the root note, you're not thinking in the right scale. It just so happens that your chord progression resolves on E minor, so the key is E minor.

It's hard to explain in text how resolution sounds. In a textbook way, it's where all tension is relieved. It's where the song feels comfortable ending on. Play this once: C-B7-Em. That also resolves on Em. To compare, play these two: C-B7-Em-C and C-B7-Em-B7. They might sound better in your opinion, but neither of them feel complete -- there is tension left over when it ends, so it definitely doesn't resolve on C or B7.

As an exercise, find out where this progression resolves: G-Am-C-D. What I normally do is play each of these once and listen for which one sounds the most complete: G-Am-C-D-G, G-Am-C-D-Em, G-Am-C-D-C, G-Am-C-D. See what I did there? I play the progression four times, ending it on a different chord within the progression each time. I hold the last chord out too.

These two examples I have are the easiest kinds of resolution to hear (it's called a perfect cadence, actually). Your progression is a little harder to hear, but it's still pretty easy. Progressions like this are called strong progressions because they have a strong harmonic movement that determines the root note. Progressions which have a more ambiguous resolution are called weak progressions. Neither of them are considered better or worse, they're just names.


There's one of my more recent posts on the subject. Hope you understand it.
Last edited by Eastwinn at Sep 11, 2009,
#5
pick a string - play chromatically up it - (one fret at a time). Some will sound 'right' these are prrobably the roots or obvious tones (5ths etc.) from there you can work a root note quite easily. most 'popular' music (not just pop but a majority of 20th/21st century music) is major or minor. Get those 2 things and you are well away to improvving over it. Should work no matter what instrument it is played on/if it has any lick you don't know.
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