Help understanding the chord analysis and key of song, "You Are" by Kem

One of many (most?) songs written in one key and transposed (in this case down). I've missed out most of the chord extensions. I'm hearing it in E minor i.e. as the keybordist played, but of course it sounds in D# minor.

3 times repeat
Emi C Emi C
Emi C Af G
End 3 time repeat

Ef F G Cmi
Ef F G Cmi

Ef (Fmaj on top), F G C
Ef (Fmaj on top), Fsus9, Emi sus9, C

Emi C Emi C Af G

etc..

I've deleted my initial answer and have taken a 180 degree turn on this.

First let me layout what I think the chords are...

D#m7 B(sus2) E(sus2) F#

...with the melody working around F# G# A#.

D(maj7) E(sus2) F# Bm(sus2)

...with the melody working around F# C# B descending back to F#.

I think that's roughly what's happening.

IF I have those m7 and sus2 chords right, then the whole song has F# and C# sustained throughout. Combine that with F# major being the only plain major chord and it makes a solid case for a tonic of F#.

Now, about the E chords. The sound like the third is omitted and replaced with a second leaving them sort of ambiguous in terms of major/minor. But, in the melody there is a G# which would be the major third of the E chord if they weren't sus2. So, the implication is E major. Now it seems pretty clear both sections have E to F# as bVII to I.

In the verse it's a vamp between D# and B ending with E to F#. Roughly IV bVII I dressed up with suspensions.

The refrain is essentially D, E, F# as bVI bVII I.

The song gives two presentations of bVII I where I is rhythmically shifted by a bar and the submediant is a borrowed chord in the refrain as a way to differentiate the two sections.

I still to my point about pop music and key ambiguity. This verse would probably be notated with an F# major key signature and accidentals for bVII. The refrain sort of shifts to minor, but it might be just as well to use a F# major key signature and accidentals so that the borrowed chords are high lighted as such. This where I think it might be best to say it's nominally in F# major in terms of key signature but not in terms of major/minor system cadences defining a key.

Trust your guts! If F# feels like home, it must be the key!

The song bases on chords from the key of F#, but then also uses many other chords. You could call it a modulation (when you switch to another key for a while), but in this case I believe a more accurate name isquite modal interchange: chords D, E, Bm are borrowed from the key of F#m. (I don't believe there is Em chord, it's rather Esus).

Here is a web page where you can enter a sequence of chords and get a list of all the parent scales that fit one or more of those chords:

http://www.micrologus.com/tools/online_harmonic_analyzer

Basically, when you see the same scale under several chords, it's an indication that this is the tonal center of that group of chords.