Finding a "quasi-dominant" in different modes

Tannin

In a practical sense I daresay I can work this out for myself, but I'd like to know what the "proper" way of doing this is.

Suppose I'm playing in a particular mode. My example is E phrygian. I want a chord that is going to bring me back to the tonic. In E major, the strongest pull is from the dominant, the V chord,  B7 > E. In E minor, the usual thing seems to be to "cheat" a bit and play a B7 anyway, even though, strictly speaking, the v chord is minor and B7 is out of key. 

In E phyrgian, the diatonic V chord is B half-diminished, which has a very strong pull sure enough, but it pulls us to C, not really back to the tonic  Em. 

Should I play a B7 anyway? Or do some other thing? (Meaning "should" in the sense of "what is the most traditional?") 

To my ear, the obvious chord in E phrygian that really, really wants to come back to the tonic is the II chord, F. But what does the theory say?

More broadly, and without asking for an epic-length essay  of an answer (well OK, maybe I am) how about the other common modes?

stratman3142

Tannin said:

...In E minor, the usual thing seems to be to "cheat" a bit and play a B7 anyway, even though, strictly speaking, the v chord is minor and B7 is out of key. 

In that context I think of the B7 as being part of the E harmonic minor scale.

Keefy

F7 - think of it as the b5 substitution for B7.

viz

Yeah, you can always do a “perfect cadence”, i.e. going up a perfect 4th from the dominant position (or “5 chord”) to the tonic (or “1 chord”)

You can do it in Ionian and Lydian (the only two scales that have a major 5 chord (a “V”) in their diatonic scales)

You can also “cheat” as you put it, and deploy a V or a V7 in any other scale - minor, dorian, phrygian, mixolydian, as well as any other non-diatonic scale you fancy playing in, like Hungarian major for example, in fact, whatever scale you like. Even though all those scales strictly speaking call for a minor 3rd on the dominant. Basically whenever you want to return to the tonic chord, you can come off a V7 if you fancy. That’s just making music. There is NO RULE that states you have to, or even you should, stay within the diatonic notes. In fact I can’t think of a single classical piece that does!

And of course you can also deploy a dominant chord any time you want a perfect cadence, even if you’re not returning to the 1 chord. For example in major, you can do III7 - vi. You don’t have to do iii - vi. That’s called inserting a “secondary dominant”. It’s a way of creating a strong resolution to the 6 chord. Instead of just going from the 1 to the 6, you can go via the 3, and majorize it, thus making the resolution to the stronger, or more “perfect”. In other words, making a “perfect cadence”. Like in the first verse of That’s Life.  The III7-vi basically behaves like a V7-i. 

Cranky

I like the way it sounds running a G/Bdim arpeggio 

up to a high F then fall back into an Em for the finish.

Also, Em and Cmaj7 are basically the same chord.  As is the Bdim and G7.

Kittyfrisk

Sounds like you might need to try B/D/S Minor.
Less dominance....