Dubstepforum.com

djbmc wrote:I think ppl need to remember that music came first and scales and keys were developed to help explain why some notes sound good together and others don't, of course if you're having trouble moving your sequence of notes onwards and want some kind of scale to work in then you're right to try and figure it out. That doesn't mean that what you're playing are all notes within a standard western scale, it could be a plain diatonic progression.

There are also things such as auxiliary notes and passing notes that may explain it:
http://en.wikipedia.org/wiki/Nonchord_tone

Ashta wrote:I was in the exact same situation with these same notes (and it was a bassline too) some time ago... If I recall correctly, I added some synth chords and a melody on top just playing by ear and then figured out that the riff had a key change from B harmonic minor to Amaj

.onelove. wrote:How do you know what the root note is?

I've never understood for instance, why A minor is supposedly different to C major, when they're using the same notes? How would you be able to tell one from the other.