At least the ones in your mind.

I've written a piece in the key of Dmajor. Chords used are just D major (I), G major (IV) and A7 (V). It has a middle section that is almost completely hanging on a G major chord for 8 bars, with just a brief turn back to the D major chord progression it started with.

Because it is so long (and of such a different timbre/character) it kinda feels like a key change to G major, but since there are no other chords to "give away" a new tonal center to G, it may NOT be.

So...did I accidentally modulate? What key/scale should I be telling for a solo over that section (planning at present to hire a soloist to improvise) Dmajor or Gmajor? Or would either of those be helpful info?

I'm in no way afraid of being eccentric, so if one might sound "weirder" than the other, that's ok...but good to know in advance. I just want to be able to communicate.

Thanks.

kinda hard to tell without hearing it.

https://soundcloud.com/user-47797156/gob-key-test/s-GJMvj88ZiZw

OK. There's enough of it to get my point across--52 seconds. First bit, I, IV, V of D...false ending...middle 8 G major chord with a bit of a transition...return to original progression.

Bad link? It says track not found, Tangmo.

Thanks, Dave. I have it marked "private" and didn't know there is super secret decoder link required for all pesky other people.

Edited the above, but here it is again.

https://soundcloud.com/user-47797156/gob-key-test/s-GJMvj88ZiZw

After noodling over it for a bit, I would probably stick to D major pentatonic and/or D minor pentatonic, for the main section, but over that 'G' section I would stick to D major pentatonic, those are the notes that sound best to me.

But, if you are hiring someone and you want them to improvise, just let them do their thing I think.

Personally I didn't hear anything wrong with it. That middle section of 4 based on G ... it provided a tension that needed to be resolved but you actually did it in a decent manner. It resolved nicely by returning to the original progression of D G A.

In no way did that middle section sound like a key change to me. You resolved it. You could have used it to change keys but when you resolved back to the original progression, you released the tension.

Yeah.... I'd say go with it like it is.

Oh, no question that I'm going to go with it like it is. Any "key change" (if there actually is one) might be accidental, but the chords are exactly like I want them to be. The issue is "resolution", though. If I'm going to ask for a melodic lead, key matters (or certainly MAY matter). That short melody also needs to resolve and/or modulate.

The real issue is "communication" though. I've got no choice but to let him/her do their own thing, but I feel like I have some choice in how I "hear" it as everyone hears music differently, and if I can't communicate that, then I've frittered away my input.

Side note: I looked up the chord formed by all the notes of both the D and G triads. Turns out it's a Gmaj9 and no naturally occurring D based chord was listed. Might be kinda fun to ask for something of an arpeggiated Gmaj9 (or some inversion thereof) to be considered, at least in part.