"Alt" Chords

[basslyon]

Hey dude and dudettes,

I got some chords charts of a drummer (yes it's strange but work with me) for a gig on sunday which involves songs i've never heard before and musos i've never played with. oh yeah

what is a F "Alt" chord?

thanks

[onlyclave]

"Alt" means Altered chord. It's musical shorthand for #9, b9, #5, b5. You will only see it on a dominant (ie R, 3, 5, b7) chord and it's what gives you artistic license to play whatever you want. There are no wrong notes over a dominant chord, just "alterations".

For the Theory Patrol out there, superlocrian aka 7th mode of the harmonic minor scale is what you can technically play over an Alt chord. R, b2, b3, b4, b5, b6, b7. All of the alterations are included in that scale although some are there as enharmonic equivalents.

Edit:
To answer you original question, F Alt would (or could, there is no rule) be F A Cb and/or C# Eb Gb and/or G#. You would have to listen to the piano player to match what alterations he's choosing but for the most part AVOID the natural 5th and natural 9th of the chord. You will be a half step off.

[Tslicebass]

F alt usually refers to a chord derived from the altered scale. The altered scale is the 7th mode of the Melodic Minor scale. It contains a root, flat 2, flat 3, Natural 3, flat 5, sharp 5, flat 7. So in C that is C, Db, Eb, E, Gb, G#/Ab, Bb.
It is common used as a alt. dominant chord. The chord can contain any combination of root, third, flat or sharp 5th, flat 7th and flat or sharp 9th.

[basslyon]

Thank you muchly.

I hope your child will be a masculine child

[Deacon_Blues]

I've these chords sometimes but I never really knew what they were. Thanks for the info!

[PocketGroove82]

On the double bass side, there is a really long post with some great info from double bass guru, John Goldsby. It discusses the different ways to understand altered chords, different scale choices, and upper structures.

Check it out! b9s and +9s