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Sabby
04-29-2003, 08:21 PM
Hi, ive been going over the great articles on major scales by Guni. There's 1 thing im having trouble with though. It seems as if Diminished chords only have 3 notes 1 b3 b5 while your m7b5 has four notes namely 1 b3 b5 b7, correct? My friend showed me what his guitar teacher taught him to be a F#dim (spose you can show dim like this F#o?) as follows :

e|----2----
B|----1----
G|----2----
D|----1----
A|----0----
E|----x----

I saw this in a chordbook as well. Yet those notes are F# C A D# so um you see the 4 notes a b3 apart which to me logically means a m7b5 chord right? Some 1 care to show me the way :) much appreciated..

-Ryan

JAVIER
04-29-2003, 10:15 PM
HEY Ryan, first of all excuse my english cause im out of practice.
Now, if it helps..
The diminished triad itīs : 1 b3 b5 , but the diminished 7 chord
is : 1 b3 b5 o7
The only difference between the diminised chord and the minor 7 flat five itīs that the first one has a diminished seventh instead of a minor one.
The minor 7 flat five also has a diminished triad-
What i wanna know, pleeeease, is when you use a diminished 7 chord?? As the diminished 7 is not part of the scale, i wonder if you use it just to give tension to the song, if it rests on the root chord, or what.???
Thanks
Love the music

the1andonly
04-30-2003, 12:11 AM
sabby, what you're showing is an Adim7, but it could also be F#dim7. these are different than diminished chords, which are 1-3-b5, and a half-diminished m7b5 chord.

here's how you could change this Adim7 into an A dim:

(1-b3-b5)
e--5
b--1
g--2
d--1
a--0
e---
and how to change it into a Am7b5:

(1-b3-b5-b7)
e--3
b--1
g--2
d--1
a--0
e---

they are all pretty much used the same. all of these could be used to resolve to a Bb or Bbm chord. but the diminished 7s are my favorite. they have a 1-b3-b5-bb7 chord formula, where every note is a minor 3rd apart. it's symmetrical, so the Adim7 is actually the same as a Cdim7, Ebdim7, and F#dim7. hope this helps.

Sabby
04-30-2003, 07:23 PM
Yeah 1andonly that cleared things up quite a bit. Thx for the explanation ;)

-Ryan