Does the same key have both major and minor pentatonic notes?

Question

When guitarists (or musicians for that matter) talk about keys. For example they say that they are in the key of A. Does it mean it could be either A major or A minor or both?

Another example: Some guitarist teaches the E minor pentatonic scale to some beginner. It's a continuation of learning the 12 bar blues in the key of E. So he's going to learn the scale that he can use to start improvising guitar solos in that same key.

Here he uses the words: "same key". He learned E major first, then he's going to learn E minor, but the teacher say that its the same key.

Would this mean that the key of E can contain notes from both E and Em? But its a bit confusing because I heard that with the Circle of fifths the same notes in E major are D-Flat minor, A Major has same notes as F#-minor and so on. How does these things relate to eachother when talking about keys? I think I need some extra push to understand what musicians mean when they talk about keys. Thank you.

Answer 1

In naming keys, "major" is often omitted, so "in A" normally means "in A major." I could imagine someone saying "in A" to mean "A minor" in informal usage, but only if the context makes it clear that the key is A minor rather than A major.

The key (apologies) to understanding E major and E minor as the same key is the blue note. If the third scale degree is sliding around a bit, it could be a major third or a minor third, or even both at the same time. It's ambiguous. The same is true of the seventh degree (which is also, of course, the third of the dominant chord).

This ambiguity is often realized by playing the tonic major chord but using the minor third in the melody, or indeed in the guitar solo. As the Wikipedia article notes, the blue note is usually thought of as slightly lower. Pianos can't do "slightly lower," so pianists often just play the minor third, or even the major and minor third simultaneously. With the guitar, on the other hand, you can bend the pitch up rather easily, so if you want a pitch between the minor third and the major third, you play the minor third and possibly bend it sharp.

Would this mean that the key of E can contain notes from both E and Em?

Well yes, any piece in any key can contain all 12 tones. Key is a subtle concept. The most important thing with a key is the tonal center: A, E, or whatever. The second most important thing is the third degree of the scale: major or minor. But saying that a piece is in E major doesn't mean that G natural is forbidden, nor must a piece in E minor avoid G sharp. Using the note that is nominally "out of the key" provides color (hence the term "chromatic"). Blues-scale guitar solos are a well known example of that.

Answer 2

For starters, D♭ minor does not have the same notes as E major - C♯ minor does. E major and C♯minor both have 4 sharps - D♭ minor has only flats.

On to the question.

When improvising in E major - (not Em), then notes from both E pent. major and E pent. minor are often used - good players will incorporate both sets of notes (and any of the other notes which don't belong as well !)

So, when saying 'E', it will usually mean both pent. sets of notes - from a good teacher.