Dm7b5 preferred over Dø

To me of Cm7b5 and Cø are the same chord. Just different symbols for same chord. I also see a Cm7b5 as a dominant 9th without a root.

Locrian is a basic scale to use over the chord.
Locrian #2 is a more Coltrane-ish sound (mmi from 3rd of mi7b5)

 

They are the same chord to you and everyone else Doc, they both have the notes {D F Ab C}. I don't know what ryco is trying to say with his post, but that chord can imply a lot of things, first and foremost, I guess it will imply Locrian in scale terms, but it could be attached to a lot of other scales.

Also as Docbop said it can imply a dominant 9 without the root.

I prefer to use Dim7(b5) in notation because it avoids any ambiguity or misreading of the symbol.

 

They are technically the same thing, I think people just prefer the name m7b5 because it's technically not "half" diminished but more "3/4" diminished.

 

So "technically" what is half diminished? {1 b3 5 b7} or maybe {1 3 b5 b7}?

 

The answer is yes, they do mean the same thing, then.

Now, what I want to know is how you get the "ø" sign in the first place when you type. I just cut and pasted it from your post, but is there are code for it?

 

Alt + 0216 (hold down alt, type 0216 on the numeric keypad, let go of alt)

Ø

You can look up symbols like that in the character map program (start / all programs / accessories / system tools )

HTH

 

That's how I'd read it.

Good call; I'll have to remember that.

 

never mind.

 

Not to derail, but somewhat related:

I have always thought that if we are going to use "O" and "Ø" to denote diminished and half diminished respectively, for the sake of consistancy and due to the relationship of terminology, since "Ø" for half diminished, by definition is a chord taken to the 4th degree (b7), then it's related sister chord ("O" / diminished) should also automatically be taken to the 4th degree (bb7).

"dim7" or "O7" has always seemed weird to me. When the 4th degree is unneeded it could be written simply as "mb5" or "-b5".

My understanding of the implied scales is not up to many of your levels (I have a really good ear so I tend to play what I hear more than the mathmatics), so why am I wrong here?

 

The first one is min7

Second would be altered



dim7: 1 b3 b5 bb7

half dim: 1 b3 b5 b7

the half dim has 3/4 notes that make up the dim7. Therefore 3/4 diminished seems like a more suitable name than half diminished. Sorry I should have explained that earlier.

 

I like how Mark Levine (The Jazz Theory Book) sees it:

Dø = 2 pieces of information

Dmin7(b5) = 9 pieces of information

 

I think the reason why a lot of people prefer the nomenclature m7b5 (or -7(b5), or whatever) is because you see the "7" in the chord symbol, which is always nice to have, whereas simply "ø" doesn't have the visible 7 that we associate with 7th chords. Of course you could be redundant and do "ø7", which Jamie Aebersold does, I think. Regardlless of which way you symbolize it, though, its the same chord.

From a very theoretical standpoint, you can make the case that there are two separate FUNCTION's that separate the structure 1 b3 b5 b7 into two different chords, the "minor 7 flat 5" and the "half-diminished", the same way that you would separate functioning and non-functioning dominant chords. If you have a regular minor ii-V, like Dm7(b5) - G7(b9) - Cm6 or whathave you, the first chord would have subdominant, or predominant function, the same as its corresponding minor 7 chord would have if it were a major ii-V. There is a change of modality (major to minor), but the chord's function remain's the same within the chord progression. If, however, you had a CHROMATIC chord progression that related in the same way that diminished chords relate to others (descending/ascending by half-steps), then you would have something different. What I mean by that is something like the second half of the A in Night and Day, when you have a chord progression like F#m7(b5) - Fm7 - Em7 - Eb7 - Dm7 - G7. The F#m7(b5) has a diminished function, but isn't a fully diminished chord, hence, "half-diminished".

The reason why the term "half-diminished" came into vogue in the first place was because of a chord progression that behaved similarly. The beginning of Tristan and Isolde by Wagner starts dramatically on this chord and the voices all move chromatically towards resolution. You'll hear some classical people call it the "Tristan" chord for that reason.

 

IMO for the dim or "O" chord it doesn't matter how far your build it out because it is a symmetric chord. Remember in a dim chord any note of the chord can be its root.

 

This is quoting from Carol Kaye's Jazz Improv for Bass book, page 21 about subbing for the m7b5:

"m7b5 = Use the minor chord 3 frets higher: For F#m7b5 (which is also called F# 1/2 diminished - no it's not a diminished chord at all , just a term) use Am7, OR, use the 7th it's going to as a diminished: F#m7b5 goes to B7, so use Cdim over both chords, OR, use the pivotal b5 of B7 (F13, F9, or Cm9 - again only if the B7 is resolving to its tonic of the E chord), or use the major note scale 1 fret higher than the m7b5 chord: F#m7b5 is the maj7 degree of the G note-scale, but this is a sort of a last-resort, don't use note-scales much, they are boring and non-melodic - notes scales are OK a few times, but usually only as traveling notes."

This is for jazz improv/soloing. After reading all of that and trying to remember it while I'm playing............I just came to the conclusion that playing ANY note, whether it is right or wrong, can be justified in jazz improv!!!!!! In my Christian group I always tease the members by saying, "I never play a wrong note on my bass......................if it sounds wrong, I just call it JAZZ!!!" Jazz for Jesus..........a nice little alliteration!

She also said that the symbol for m7b5 the 0 with the slash through it, was first used because some writer got tired of writing m7b5 over and over again, that's all there is to that.

Johnny

 

I understood you perfectly actually. I was really making the point that it's not called half diminished because it has half of the notes of whole diminished. It's just nomenclature and it's not at all misleading in my opinion.

I was also pointing out that calling something else half diminished based on the logic you are applying doesn't work as far as I can see.

 

Yes, and also a diminished chord is one of Messiaen's modes of limited transposition, having only 3 transpositions.