So i'm an intermediate player i've played for 3-4 years. i don't really know any other scale except for the minor pentatonic and i've mastered all the shapes of it but now i'm wondering if i improvise on a song and i'm using the "A minor pentatonic" does that mean the key of the song needs to be in A minor as well? thank you for reading
Last edited by JamesGSixx at Nov 30, 2016,
Not necessarily. Certainly the A minor pentatonic is found in A natural minor. If the chord progression (or even static groove) is showing Am as the "home chord" (e.g. Am, G, F, E(7), Am), then the tonal centre is A, and the you're (mostly) using chords from A natural minor.

But you can also find a minor pentaonic off of the iv and v chords of natural minor. For example, you may play Em pent, over an Am chord, or over an Am chord progression. (THere are other sources as well, but I don't want to complicate things here).

It's primarily the chords (or melody if no chords) that, used appropriately, make the tonal centre apparent.

Some folk will talk about key just meaning the tonal centre, others will talk about key as tonal centre, and chords based on major and a few minor scales; yet others will talk about key as tonal centre, and chords from other scales.

Just be aware that typically we try and make one pitch the most prominent (by using a major or minor triad rooted off it, and other chords departing from and setting that up); and there are different scales (modes) that can be used for the majority (if not all) of the content.