"Alt" Chord?
 

What is meant by, e.g., a "D Alt" chord? I ran across this notation in a transcription of the song "It's De-lovely".

I understand the general notion that an alt chord is a chord in which one or more scale notes is flatted or sharped (e.g. E7+9 or E aug), but this seems to leave open many possibilities. Just wondering if there is some common interpretation of this notation or if it depends upon context.

Thank you!

One of the best ways for me to understand the "Alt" chord is to look at the 7th mode of the Melodic Minor scale.

For instance, the F Melodic Minor scale is spelt like this:

F G Ab Bb C D E F

The 7th mode of this scale would be:

E F G Ab Bb C D E

Which could be re-written like this:

E F Fx G# A# B# D E (Fx = F double sharp)

Which are the following scale tones of an E dominant chord:

Root - flat 9 - sharp 9 - 3rd - #11/b5 - #5/b13 - 7th - Root

Which are all notes found in an E7 Alt. chord. So you could voice it like this:

E7b5b9
E7#5#9
E7#9b13

Yeah. Altered scale etc. Secondary dominant chord. Probably altered especially with reference to the melody.

The most practical comping takeaway for guitar is that it's a dominant chord which DOESN'T work with your traditional 9th or 13th chords. Natural 5th in your chords will probably clash with the melody as well. 7b9 chords are safe and easy (diminished shape). Considered a little vanilla by jazzers. 7#9 or 7#5 is "more altered".

There is theory involved with creating altered chords, but probably the easiest real-world workaround for newbies to jazz harmony is to play bII7 Dom chords as a sub. So, Dalt = Ab9 or Ab13. Leave the bass out if that helps you hear it. Better yet, add the D back in bass.

[Theory below. Please disregard, if not interested: 7#5 (7b13) and 7b9 chord symbols may implied alter, but could also be harmonic minor and basically work with natural five. 7#9 Basically implies altered more explicitly. Alt chord symbol usually implies more explicitly that the natural five is NOT going to work , and that you need to actually pull from altered scale/melodic minor.]

Shell voicings work really well until you understand more about this stuff , or use the above bII7 sub.

I believe this answers my question.

Thanks for the other insight, as well. :)

Is a 7#5 chord somehow different than a b13 [ex. low-to-high: x76778]?

Not really, in terms of the specific traditional guitar voicing.

[Technically, yes. On piano you can play a natural five and a flat 13 in the same chord. ]

Beyond piano etc, for guitar, this means when you have 7b13 (most often written as 7#5) you can do things like play straight dom7 chord voicing followed by 7#5 voicing for movement.

[That's harmonic minor. Again, altered works as a sub for harmonic minor. Usually, "alt" more explicitly implies the altered scale, but chord symbol notation can be very inconsistent.]

Since "Alt" is not a specific chord that was kind of a lazy way to label a chord in the transcription.

Check...thanks. :cool:

One man's lazy way to label a chord is another man's lead sheet.

.

Not necessarily lazy. Depending on the circumstance, it may be the simplest way to notate. "Avoid natural five and 9 . Play sharp five/flat five and sharp 9/flat 9" doesn't roll off the tongue/pen either. :-)

It has real implications for soloing , and that's what a lot of these chord symbols are for . They indicate considerations for soloing. Again, if you're not into all of that, there are comping workarounds discussed above.

True.

Again, the 7th mode of the Melodic Minor is perfect for soloing over an Alt. chord as every note in the mode is a chord tone of the Alt. chord.

For G7 Alt, use an Ab melodic minor
For C7 Alt, use a Db melodic minor
For E7 Alt, use an F melodic minor
Etc.....

There's another cool use of this mode over an implied Alt chord when playing blues. Larry Carlton does a great job explaining/demonstrating here...

http://www.mr335.tv/index.html?chann...c/melodicminor

It's worth watching...

Simple but non specific as an "alt" chord could be a number of different chords.

The purpose of an altered dominant is to provide maximum chromatic voice-leading to the following chord. Forget about the scale on the chord itself - look at where it's going.

A D7alt chord is almost certainly resolving to Gm or G major. The core of the dom7 (root-3rd-7th) is always present, and those notes resolve as normal: root is a shared tone (5th of G), 3rd and 7th move by half-step (F#>G, C>B, or C>Bb if Gm - the only whole step move). So far, so classical.

The altered 5th and 9th can move as follows:

Ab > G or A (9th of G)
A#/Bb > A or B
Eb > D or E (6th of G)
E#/F > E or - less likely - F# (6 or maj7 of G)

You choose whichever of those (if any) you want, according to where you want your phrase to land on the G, and probably on where you're coming from on the preceding chord.
Another tip is that a 7alt chord is the same as its tritone sub (built from the same notes). D7alt = Ab7#11 (ultimately Ab13#11); only the bass note is different. Thinking "Ab7" helps remember the half-step leading idea.

The "7th mode of melodic minor" is a handy memory aid, IF you know your melodic minor scales. It's also handy for suggesting some arpeggios or pents you can play on the 7alt chord. (Eg, in this case Fm pent, or Ebm arp.) The chord doesn't derive from melodic minor, and - speaking personally - I didn't understand how to use this scale until I realised how the voice-leading worked.

Right, but when you are getting into altered, you're really talking about jazz basically. In jazz, a D7 chord symbol implies certain things. Basically it implies that a natural 5 will work. It implies that it could be D9, D11, D13 etc. If the harmony truly implies altered though, basically NONE of those are true. Again, how else do you notate that?

You could call it D7#5 or D7b13, but those can just as well be harmonic minor most of the time, which includes a natural 5. It's kind of a guitar- specific viewpoint to view voicings as basically being one specific thing. A handful of pet voicings is really fine. 7#5 is safe to play on guitar if you needed something to play, but pianists simply don't think about chord voicings the same way.

If you want to think of the "alt" thing as being more for piano players or whatever, it might simplify things. If you ever decide to play around more with the jazz , there are a lot of great voicings from altered. They're mostly used by subbing in melodic minor chords as discussed above and not thought of so much in terms of the specific altered tones of the chord of the moment, like F-7 above. That's another reason why the alt symbol works well. It's really streamlined when you start thinking about it that way.

D7alt to pianists is Ab13#11, Cm7b5 Ebmin-maj7 as much as it is "D7-anything"... Easier to think about and play with, but of course, they can play melodic minor in the FIRST place.

Nomenclature works out fine when applied to contextual conventions that are understood and agreed upon
among a group of people. Within the wider population there can be other interpretations of meaning.

Piano can be trickier given more available space and number of notes. There is room for say playing melodic
minor chordal harmony right underneath major key harmony and melody (polychords) - chord naming, if given, likely
referring to the melodic minor based chords.

This thread has been an excellent education on the subject of altered chords. But...I'm not sure I've ever seen 'alt' used as a chord symbol on a chart or song sheet. Usually, the alteration is specified, as in #5, b5, etc., isn't it? I've never seen it in a chord book. And an internet search reveals the same thing as this thread: a lot of good stuff about altered chords in general, but no examples of it as a chord symbol.

So I guess I wouldn't worry too much about the "alt" chord per-se. Next time you see an altered chord, the specific alteration will probably be spelled out for you. You can build it, even if you don't understand it. That's how it works for me, anyway. I don't really understand chords more complicated than diminished or half-diminished (m7b5) chords, but I know how to "build" the more complicated chords based on the specific chord symbol. Chord symbols are specific, "alt" is not.

Or, could it be an error? Maybe a "note to self" from the transcriber, this is an altered chord of some kind, figure it out later -- but it never got fixed?

Anyway, this is Gershwin, right? Whatever it is he's doing with harmony is way beyond me. And I'd guess that even experts might struggle with it. I take all charts and transcriptions with a grain of salt.

Again, very educational thread, thanks...