"Why" re: same chord, two names

Jazzaferri

Ahhh sensible ole Bones

SteveGypsyJazz

Here's one more explanation:

As an example: an F7 chord has the same fingering as a B7 (b5/b9) chord.
[playing the inversion from lowest/5th string to highest/2nd string (Eb A C F)]
[in the case of the B7(b5/b9) chord the notes for comparison are (D# A C F)]

F7 is in the key of Bb major
B7(b5/b9) is in the key of E major (or as a substitution for plain B7 it resolves to E major)

If I'm playing in the key of Bb major I'd call it an F7
If I'm playing in the key of E major, I'd call it a B7(b5/b7)

It's the same chord, but we refer to each according to its "key center".

Jazzaferri

B7 is a tritone substitution for F7 in Bb Major. It could work depending on the context.

Lango-Django

Hey, Jazzaferri--- and all my other djangobooks buddies--- speaking of tritone substitution, I have a question for you.

I'm no expert, but it seems as if tritone substitution is most commonly used in playing over dominant seventh chords.

Question: can it also be used over tonic and subdom chords, or would that sound too weird to our ears?

HotTinRoof

Excellent thread 8)

Essential theory knowledge. I still need my pencil and paper to figure this stuff out. You guys with your instant recall are inspiring.

dennis

tacosandbeer wrote:

Wow! If you're going to be 'nitpicky', in the key of C the notes A C E make up an A minor triad, not a 'plain ol C major chord'. What's up with that bit of misinformation.

that'sm e having a serious brain fart, and you having a serious case of smartass lol

Jazzaferri

Lango

The use of a TT sub is usually straightforward in a V-I resolution. If the Chords are say G7 resolving to C using a C#7 as a substitute for G7 shouldn't create any problems unless the melody has something strange going on. In my example if the melodic phrase hangs on either the 4 (F#) or the major 7 (C) while playing the TT sub then that would sound pretty dissonant.

If a dominant chord is not used as a V then the TT sub idea starts to get pretty complicated about when it sounds better or not so better maybe even downright strange .

Graham_Fellows

Yeah it's just a case that two chords with the same notes can fit in different contexts - which is to say that you might want to choose one name over another because it will give you a few more clues about what that chord's job in the progression is (i.e a tonic, second chord, dominant etc) - which can give you more hints as to what to play over it.

Like if you played minor swing with simple 3 note chords, Aminor, Dminor and E7. The A minor would be made up of the notes ACE. So you could call that 'a minor', but equally you could legitimately call it Cmaj6 (made up of the root, third and sixth but in a different order). You wouldn't call it Cmaj6 though, because it's more useful to call it A minor, because it makes it more clear that the A minor is the home / tonic chord. Especially when you see the D minor and the E7 in it and their relationship / resolution to the tonic will be more clear, instead of a random sequence of chords.

On the other hand, it can be really useful to be aware of some of the other names of chords with the same or similar notes, for substituting cool sounding chords against the original one which still fit, but soud a bit more interesting - same with scales and arpeggios. I tend to not worry about the actual notes in the chord though, being a typical guitarist and just learn that a half dimished chord a third up from a seventh chord that you want to substitute it for sounds good, playing b minor runs over an E7 sounds good (see the bit on django's tiger in the 1st chorus, first a section E7, F7, E7 bit)

bryanology

Tritone subs are usally for dominant chords, I think. However there are plenty other types of substitutions for your tonic and subdominant chords; and I think thats where alot of the 'double' chord names start to confuse folks. Like everyone has been saying the Amin7=C6, there's an easy substitution. A more legit tri-tone sub for a min chord is a min6 for DIM7, like Amin6(or min7) to EbDIM7 is common for the 'vi' in a rhythm changes I vi ii V chord prog. Just keep the 3rd and the 7th(or 6th for us GJ-ers) true to the original chord(from your chord chart) and bulid your own subs! then arpagiate that chord over the original chord. its great fun

On the topic of double names for chords, I think composers and "arrangers" try to quantify all chord changes into their simplest form. Meaning, they will re-name and re-define chords to make them into the most theoretically sound progressions, this makes the improvising eaiser and sometimes gives more freedom for the soloist.
Basically turning everything they can into a ii-V-I or any other type of fimiliar jazz resolution, while staying true to the harmony and melody.
I'm still new to jazz but I would guess that in the jazz world, just like real world, there are many different reasons for different dialects. Someone may call a chord: E7(9), the next guy: Bmin6, and the next guy: E7(9)/B, and the next guy: G#min7b5. There all the same NOTES, what usually decides is the NEXT chord.
-The E7(9) is on the chart if the following chord is Amaj.
-G#min7b5 if were moving towards the C#7 then F#(iib5-V-i).
Ect as you plug in new changes. I might just play a Bmin6 for all of them, though, Django said its ok.

Jazzaferri

To clarify for those who are not theory hounds a tritone substitution is a chord that is substituted for a chord nd the root of the sub chord is a tritone away from the root of the original chord. Tritone being the mid point ofmn octave either a b5 or a #4.

Chord names should be written the the context of their harmonic function ... But often aren't. Just like you find on led sheets there re lots of odd(wrong) chords. Some are miss written others are we'll......just very odd.

Aminor7 can also be written as C6/A. Which means you play the c6 with the A as the bass note. Both would be played a,c,e,g. The second might be used in a progression walking the bass line down. For example Cmaj7, C7/Bb ,,C6/A ,G7. In this example the bass line walks down C,Bb,A,G