So I started to write a little tune, found a great place to put a Dim7 chord, and then I don't know if I forgot or if i never knew it, but I couldn't find were to solve it to...
I know that there's the Dim Triad, but with the seven (not on the scale) I wasn't sure where should it go...

please no "music is free and you can take it wherever you want" posts...
I looking for the "legal"\"legitimate"\"theoretical" answer...

Thanks,
Muss

Is the root Dm7? If not, in what key is the tune?

Hi Muss,
It's hard to answer your question without hearing the music :)
My advice is to think in terms of "tension and release." The diminished 7 chord is an unstable, ambiguous, tense chord. So you'd tend to use it at a point in the music where you are trying to be dramatic, or move from one place to another, or create suspense.

One place you will hear the diminished chord a lot is in the blues, especially jazzier blues. In a 12-bar blues form, you play the I chord (C7 in the key of C, for example) for 4 bars. Then you go to the IV chord (F7) in bar 5. Normally, you would play IV for 2 bars, then go back to I in bar 7. But sometimes, you substitute a #iv diminished chord (F# diminished 7) in bar 6, so the progression is F/F#dim7/C. It keeps you from getting "stuck" on the IV chord, helps you get back to I.

I know that is abstract, but I hope it helps!

I meant Dim = diminished
not Dim= D minor
I was playing around the key of F major;
playing Fmaj7(F-A-C-E), then Fdim7(F-Ab-Cb-Ebb) and then I played (G-A-C) (C6 or A7 without the E- actually not sure what's this chord's name should be...) which sounded nice
now I add another question, and maybe it just because I'm tired or my ears playing tricks on me , but am I missing a simple II-V-I progression or something basic like that?

Muss, I just re-read your question. I think I may have misunderstood a little. "Which chord comes after a diminished 7 chord?" right?

Well, one example is the one I mentioned in my last post: in a blues, you can go from #ivdim7 back to I.

Another way you can use the diminished is as a viidim7 to I progression. Bdim7 to CMaj in the key of C.

And there are more options, too.

The neat thing about the diminished 7 chord is that it is symmetrical. There are really only 3 of them. Bdim7 is exactly the same notes as Ddim7, Fdim7, or Abdim7, for example. So you can use them to go off in some interesting and unexpected directions.

Hope that's a better answer!

Muss, I just re-read your question. I think I may have misunderstood a little. "Which chord comes after a diminished 7 chord?" right?

Well, one example is the one I mentioned in my last post: in a blues, you can go from #ivdim7 back to I.

Another way you can use the diminished is as a viidim7 to I progression. Bdim7 to CMaj in the key of C.

And there are more options, too.

The neat thing about the diminished 7 chord is that it is symmetrical. There are really only 3 of them. Bdim7 is exactly the same notes as Ddim7, Fdim7, or Abdim7, for example. So you can use them to go off in some interesting and unexpected directions.

Hope that's a better answer!

now you've got the question !

first, thanks for the quick answers dudes!

But when I was playing it the diminished chord root was the same as the root chord (Fmaj7 to Fdim7 -by the way I just love the way it sounds...), so in this case I should think of the diminished chord as if it's not from I(F) but from the Ab, or Cb...?

I meant Dim = diminished
not Dim= D minor
I was playing around the key of F major;
playing Fmaj7(F-A-C-E), then Fdim7(F-Ab-Cb-Ebb) and then I played (G-A-C) (C6 or A7 without the E- actually not sure what's this chord's name should be...) which sounded nice
now I add another question, and maybe it just because I'm tired or my ears playing tricks on me , but am I missing a simple II-V-I progression or something basic like that?

I hear that as C6 personally. It sounds good because Fdim7 is the same as Bdim7, which is the vii of C. You can also think of it as G7 with the root raised a half step to Ab (Abdim7).

C is the V of F, which is a really common place to modulate to.

Edit: A minor makes sense too, because it is the relative minor of C, another really common modulation.

I hear that as C6 personally. It sounds good because Fdim7 is the same as Bdim7, which is the vii of C. You can also think of it as G7 with the root raised a half step to Ab (Abdim7).

C is the V of F, which is a really common place to modulate to.

Edit: A minor makes sense too, because it is the relative minor of C, another really common modulation.

I think I'm starting to get it....
now it makes sense...
again, thanks so much Mushroo

I hear that as C6 personally. It sounds good because Fdim7 is the same as Bdim7, which is the vii of C. You can also think of it as G7 with the root raised a half step to Ab (Abdim7).

C is the V of F, which is a really common place to modulate to.

Edit: A minor makes sense too, because it is the relative minor of C, another really common modulation.

You like the sound of that because it has really great bass movement. Fmaj7 > G#dim7 > Am(7).

That is a common cadence in a minor key: VImaj7 > viio7 >i. Remember, not all songs start on the I chord :)

Edit: To answer the question the root of a fully diminished chord usually resolves up by half-step.

I hear that as C6 personally. It sounds good because Fdim7 is the same as Bdim7, which is the vii of C.

vii of C is Bmin7(b5), not Bdim7.

playing Fmaj7(F-A-C-E), then Fdim7(F-Ab-Cb-Ebb) and then I played (G-A-C)

That last chord could be interpreted as an Amin7, in which case your Fdim7 is essentially a substitute for E7. That would make a classic VI-V-i progression in the key of A minor.

Diminished chords most often function as subs for dominant chords in this way, and as others have mentioned, each diminished chord could potentially sub for any one of four dominant chords (in the case of Fdim7, those would be E7, G7, Bb7, and Db7).

That last chord could be interpreted as an Amin7, in which case your Fdim7 is essentially a substitute for E7. That would make a classic VI-V-i progression in the key of A minor.

Diminished chords most often function as subs for dominant chords in this way, and as others have mentioned, each diminished chord could potentially sub for any one of four dominant chords (in the case of Fdim7, those would be E7, G7, Bb7, and Db7).

I think his Fdim7 is actually a G#dim7 in third inversion resolving to A minor. Fdim7 doesn't work functionally in A minor even as a secondary dominant. G#dim7 however, is an inversion of Fdim7 and that does function.

Without knowing his entire progression it's hard to give an accurate analysis.

vii of C is Bmin7(b5), not Bdim7.

Bdim7 works as the leading tone in C minor though.

For me in most cases a dim chord is a rootless 7b9 chord. In other words any note of a dim chord can be the 3rd of a 7b9 and they get used that way quite a bit. The another possibility is it is being used as a passing chord. In Blues or Gospel you will hear a dim chord used to setup a change. Like going from I to IV, you will hear I, IV dim, IV7.

So I started to write a little tune, found a great place to put a Dim7 chord, and then I don't know if I forgot or if i never knew it, but I couldn't find were to solve it to...
I know that there's the Dim Triad, but with the seven (not on the scale) I wasn't sure where should it go...

please no "music is free and you can take it wherever you want" posts...
I looking for the "legal"\"legitimate"\"theoretical" answer...

Thanks,
Muss

But the legitimate answer *is* "wherever you want" - the dim7 chord is purposefully ambiguous. It was built for it from the ground up. It pretty much says "I'm about to go somewhere else."

A decent rule of thumb is that the tritone (flat 5) wants to resolve "outward" - if one note goes up, the other wants to go down. If you play with this you'll see that there are really only 2 chords you can resolve to, a major chord a half step up from either note, the other options are inversions and substitutions.

B, F -> C, E (C major)
F, B -> Gb, Bb (Gb major)

This phenomenon is part of the driving force of the V7 -> I cadence.

The dim7 is two tritones and gives you four potential places to go. The B, F tritone as described above and the Eb, A tritone for an Emaj or A#maj resolve. Though neither resolve will feel complete because neither tritone was dominant (no pun intended). This ambiguousness is part of the beauty of the chord - it gives you so many options, though none of them are truly satisfying. A lot of jazz is built on this type of ambiguity, which is why many people find it "sophisticated" or "heady" and otherwise difficult to follow for someone with pop music sensibilities. A jazz soloist would love this type of chord because the ambiguity allows them to go anywhere they want.

If you feel the need for a powerful resolve to this (which is sort of missing the point), emphasize one tritone over the other, or just drop one entirely for a half a beat before going in to the new chord. I don't know if this is the theoretically correct thing to do, but it does give a more powerful resolve than leaving both tritones hanging the whole time.

Edit: I should point out the importance of substitutions here. You really only need that major 3rd *somewhere* in your chord, and you don't 100% necessarily need it coming out of a dim7, you can sort of fudge it a bit. In a triad you have 2 possible places to put a major 3rd: CE can be CEG (C major) or ACE (A minor). Add a 7th of some sort or other and you multiply the number of places you can put that major 3rd. And as DocBop points out, even this rule doesn't have to be strictly followed as his resolves to a minor 3rd, though the IV7 continues the ambiguity shifting the tritone somewhere else.

I think his Fdim7 is actually a G#dim7 in third inversion resolving to A minor. Fdim7 doesn't work functionally in A minor even as a secondary dominant. G#dim7 however, is an inversion of Fdim7 and that does function.

Without knowing his entire progression it's hard to give an accurate analysis.

Of course without hearing his song, we're speculating somewhat about where he's heading harmonically. But the Fdim7 (or G#dim7, if you prefer to think of it that way) is really just an E7(b9) without the root. Very common in the key of A minor.

Regardless of the song in question, and I ask respectfully so that we don't have a Mutedeity/Onlyclave pissing match here, but how can you omit it root of the chord and still maintain the functionality of the chord progression? You can omit upper extension (like the natural 11th over a major quality chord because it forms a minor 9th in an inner voice), you can omit a dominant 7th because G and G7 function the same way within C major, one just has more tension, and you can omit the 5th from a chord because that member is strongly reinforced by the second harmonic of the root note (in 4-part SATB harmony, a root position perfect authentic cadence is realized in the ultimate chord by tripling the root and omitting the 5th). You can't omit the 3rd because it dictates the quality of the chord and you can't omit the root because, well, it's the root of the chord. It dictates the progression and function o the chord.

Fully diminished chords being all made of stacked minor 3rds are ambiguous in their identity because they can be transposed to easily which is why I said his Fdim7 is probably a G#dim7 (enharmonic renaming of the 3rd member) and it is in an inversion (I played it on piano based on the OPs description). E7(b9) and G#dim7 both function as dominant function chords within an A minor tonality but the root movement of G# makes more sense functionally. The chord has a name.

I'm getting verklempt. Talk amongst yourselves. The subject: Omitting the roots.

Regardless of the song in question, and I ask respectfully so that we don't have a Mutedeity/Onlyclave pissing match here, but how can you omit it root of the chord and still maintain the functionality of the chord progression? You can omit upper extension (like the natural 11th over a major quality chord because it forms a minor 9th in an inner voice), you can omit a dominant 7th because G and G7 function the same way within C major, one just has more tension, and you can omit the 5th from a chord because that member is strongly reinforced by the second harmonic of the root note (in 4-part SATB harmony, a root position perfect authentic cadence is realized in the ultimate chord by tripling the root and omitting the 5th). You can't omit the 3rd because it dictates the quality of the chord and you can't omit the root because, well, it's the root of the chord. It dictates the progression and function o the chord.

Fully diminished chords being all made of stacked minor 3rds are ambiguous in their identity because they can be transposed to easily which is why I said his Fdim7 is probably a G#dim7 (enharmonic renaming of the 3rd member) and it is in an inversion (I played it on piano based on the OPs description). E7(b9) and G#dim7 both function as dominant function chords within an A minor tonality but the root movement of G# makes more sense functionally. The chord has a name.

I'm getting verklempt. Talk amongst yourselves. The subject: Omitting the roots.

This is a debate that's been going on for a century or more with heavy weight composers & theorists on both sides.

iim7b5 ---> V7 ---> i

So the most obvious place to take it is a dominant 7 chord a fourth up (or the tritone substitution for that chord, a dominant 7 chord a semitone down). If you wanted to go directly to the root in a major key you could just take it a semitone up to a major tonic chord.

Sorry if someone already posted this I've not got time to read the rest of the thread atm.

Edit: do you mean a fully diminished 7th chord, so a dim triad with an enharmonic major 6th as the 7th, or a m7b5 with a minor 7th? If its a fully diminished chord I find they are best used chromatically as passing chords (IE. voice lead into them by raising the root of a major chord, dropping the fifth of a minor chord etc.) or if you wanted to use it theoretically the only real use I can think of is as the chord built on the raised 7th degree of the harmonic minor scale, so you could resolve it up a semitone to a minor tonic chord or take it to any other chord inside that minor key. Fully diminished chords are great for modulating between minor keys too as the same notes can function as multiple different diminished chords depending on which note you treat as the root, you can effectively resolve it to a minor tonic chord a semitone above any of the notes of the chord.

Regardless of the song in question, and I ask respectfully so that we don't have a Mutedeity/Onlyclave pissing match here, but how can you omit it root of the chord and still maintain the functionality of the chord progression? You can omit upper extension (like the natural 11th over a major quality chord because it forms a minor 9th in an inner voice), you can omit a dominant 7th because G and G7 function the same way within C major, one just has more tension, and you can omit the 5th from a chord because that member is strongly reinforced by the second harmonic of the root note (in 4-part SATB harmony, a root position perfect authentic cadence is realized in the ultimate chord by tripling the root and omitting the 5th). You can't omit the 3rd because it dictates the quality of the chord and you can't omit the root because, well, it's the root of the chord. It dictates the progression and function o the chord.

Fully diminished chords being all made of stacked minor 3rds are ambiguous in their identity because they can be transposed to easily which is why I said his Fdim7 is probably a G#dim7 (enharmonic renaming of the 3rd member) and it is in an inversion (I played it on piano based on the OPs description). E7(b9) and G#dim7 both function as dominant function chords within an A minor tonality but the root movement of G# makes more sense functionally. The chord has a name.

I'm getting verklempt. Talk amongst yourselves. The subject: Omitting the roots.

No disrespect meant here, either. :) When I play the OP's progression (FMaj7-Fdim7-Amin), it sounds like VI-V7-i to me, albeit with a slightly unusual root movement. Really, I don't think you and I fundamentally disagree here. We both view the second chord as a dominant setting up the minor i chord. Functionally, the chord actually works fine without the E root (and jazz musicians frequently omit roots from chord voicings). Try playing Fdim7-Amin, then play E7(b9)-Amin. They sound almost exactly the same to my jazz ears. ;)

I think that it works very nicely to use a diminished chord on the 4th or 7th in a minor key. That way you get some nice voice leading going, especially with the leading note

BTW, there is a beautiful Luther Vandross tune (Nancy Wilson did a great version of it as well) called "Love Won't Let Me Wait" which goes: Bmin9-Fdim7-AMaj9

Although it resolves to a Major tonic instead of minor, this is otherwise the same dominant-tonic movement that the OP came up with. Interestingly, on Luther's version, some of the verses go Fdim7-AMaj, and other verses go E7-AMaj. The difference is very subtle, but the functional resolution is the same.

Just so you guys know, a diminished chord doesn't always take on the role of a dominant function. It's intending as a chromatic passing harmony that can coincidentally imply dominant function, but doesn't always have to. For example, in the progression Dm7 Dbo7 | Cm7 F7 | Bbmaj7 the Dbo7 doesn't contain the tritone of the dominant of Cm7, but does chromatically voice lead into it nicely, aided by the chromatic root motion. Diminished chords can also resolve to a maj7 chord of them same root, which is a common sort of thing in Jobim tunes (No more tears, quiet nights of quiet stars, etc). It's also a common reharmonization that guitarists/pianists do on the first bar of Misty (Ebo7, Ebmaj7, Bb-7, Eb7, etc). This harmony comes from the classical concept of the auxiliary triad.