I imagine this will end up being another modal discussion but still haven't made the leap from tonalities to naming them. I was playing the notes of the A major scale (I think the same notes as E dom7 scale) over an E major chord and E drone, and it sounded realy cool. If this is a mode, what is it? It certainly didn't sound like I was playing an E7th tonality or in A major, when I played an E7 chord or A bass drone the whole sound changed. I can't wait to hear the theory guru's set me straight on this, I don't know why it isn't obvious to me what going on with this sound.

If you play the A major scale over an E major chord, you are using the 5th of the scale as a root hence the mixolydian mode (E mixolydian).

Over an A major chord, you are using A ionian (based on the first tone of the scale) which is the same as A major scale.

Yep, mixolydian, which compares to the seven steps of the major scale/mode like this:

Major: 1 2 3 4 5 6 7

Mixolydian: 1 2 3 4 5 6 b7

Before the modal heavies jump in on this - it sounds like a good explanation for why an A blues harp sounds better if you're playing guitar in the key of E.
If so thanks for solving a puzzle I've pondered over for many years

Thanks guys, I knew you would came through. I only messed around with the sound for a few minutes till I realized I wanted to know in theory what I was playing. Putting a name to these sounds will help me remember them in the future.

Gruupi--

Check the theory thread, first post.

Try these over an E drone:
jam w/the notes from the D Major scale--you'll get the Dorian mode

notes from the C major scale over E drone--E Phrygian

notes from the B Major scale over E drone--E Lydian

A major over E drone--Mixolydian

G Major over E drone--Aeolian (E natural minor)

F Major over E drone--the rarely used Locrian mode

Try the Phrygian mode w/ both major and minor chords. E Phrygian over E major will give you a Middle-Eastern/Andalusian (flamencoish)/arabic/Jewish-type thing

Many blues, funk and rock riffs are built on the Mixol. mode... for example, Day Tripper by the Beatles. Many celtic tunes, as well as old church songs are built on Dorian, and Mixolydian modes.

Have fun!